Product line management in hospitals: an exploratory study of managing change

Hospitals often have looked to industry as a source of solutions to business problems. In recent years, they have begun to adopt a concept that has been used by manufacturers for more than 50 years--product line management (PLM). One characteristic of PLM is the designation of a product champion whose responsibility it is to promote the product both inside and outside the organization as well as to view for organizational resources to support the product. This article presents the findings of an exploratory study that indicates that although many hospitals are successfully utilizing PLM, a number of barriers to the implementation of this concept remain.

Bruises in infants and toddlers: those who don't cruise rarely bruise. Puget Sound Pediatric Research Network

OBJECTIVES

To determine the frequency and location of bruises in normal infants and toddlers, and to determine the relationship of age and developmental stage to bruising.

DESIGN

Cross-sectional survey.

SETTING

Community primary care pediatric offices.

SUBJECTS

Children younger than 36 months attending well-child care visits.

METHODS

Prospective data collection of demographics, developmental stage, and presence and location of bruises. Any medical condition that causes bruises as well as known or suspected abuse was also recorded. A chi2 test or Fisher exact test was used to determine the significance of differences.

MAIN OUTCOME MEASURES

Presence and location of bruises as related to age and developmental stage.

RESULTS

Bruises were found in 203 (20.9%) of 973 children who had no known medical cause for bruising and in whom abuse was not suspected. Only 2 (0.6%) of 366 children who were younger than 6 months and 8 (1.7%) of 473 children younger than 9 months had any bruises. Bruises were noted in only 11 (2.2%) of 511 children who were not yet walking with support (cruising). However, 17.8% of cruisers and 51.9% of walkers had bruises (P<.001). Mean bruise frequency ranged from 1.3 bruises per injured child among precruisers (range, 1-2 bruises) to 2.4 per injured child among walkers (range, 1-11). The most frequent site of bruises was over the anterior tibia and knee. Bruises on the forehead and upper leg were common among walkers, but bruises on the face and trunk were rare, and bruises on the hands and buttocks were not observed at any age. There were no differences in bruise frequency by sex. African American children were observed to have bruises much less frequently than white children (P<.007).

CONCLUSIONS

Bruises are rare in normal infants and precruisers and become common among cruisers and walkers. Bruises in infants younger than 9 months and who are not yet beginning to ambulate should lead to consideration of abuse or illness as causative. Bruises in toddlers that are located in atypical areas, such as the trunk, hands, or buttocks, should prompt similar concerns.

Symposium overview: the role of genetic polymorphism and repair deficiencies in environmental disease

A symposium of this title was presented at the 37th Annual Meeting of the Society of Toxicology held in Seattle, Washington during March of 1998. The symposium focused on heritable variations in metabolism, DNA replication, and DNA repair that may predispose humans to environmental diseases. Human metabolic, replication, and repair enzymes function in protective roles. Metabolic enzymes are protective because they detoxify a stream of chemicals to which the body is exposed. Replication and repair enzymes are also protective; they function to maintain the integrity of the human genome. Polymorphisms in the genes that code for some of these enzymes are known to give rise to variations in their protective functions. For example, functional polymorphisms of the N-acetyltransferases, paraoxonases, and microsomal epoxide hydrolases vary in their capacity to metabolize environmental chemicals. Specific isoforms of the N-acetyltransferases and microsomal epoxide hydrolases are increasingly associated with incidences of cancer attributable to exposure to these chemicals. Thus, maintenance of cellular-growth homeostasis, normally and in the face of environmental challenge, is dependent on an inherited assortment of metabolic isoforms. Since replication and repair are also protective cellular functions, and since mutations in genes that code for these functions are associated with tumorigenesis, one can reasonably speculate that common functional polymorphisms of replication and repair enzymes may also impart susceptibility to environmental disease.

Tissue compartment-specific estrogen receptor-alpha participation in the mouse uterine epithelial secretory response

17Beta-estradiol (E2) acts through the estrogen receptor (ER) to regulate uterine epithelial cell growth, proliferation, differentiation, and secretory protein production. We have previously shown that E2-induced uterine epithelial proliferation is mediated indirectly by ER alpha-positive stroma; epithelial ER alpha is neither necessary nor sufficient for E2-induced uterine epithelial mitogenesis. In the present study, we addressed the question of whether production of uterine epithelial secretory proteins and their messenger RNAs (mRNAs) requires ER alpha in stroma, epithelium, or both by analyzing tissue recombinations composed of uterine tissue from adult ER alpha knockout (ko) and neonatal BALB/c (wt) mice. Stroma (S) and epithelium (E) were separated by trypsinization, and four types of uterine tissue recombinants were prepared: wt-S + wt-E, wt-S + ko-E, ko-S + wt-E, and ko-S + ko-E. These tissue recombinants were grown as subrenal capsule grafts in intact female nude mice for 4 weeks, at which time the hosts were ovariectomized. To assess the production of secretory proteins and their mRNAs, 1 week after ovariectomy the hosts were given three daily injections of oil or E2 (100 ng), and then 24 h later the grafts were recovered and used for either ER or lactoferrin (LF) immunohistochemistry. To assess steady state mRNA levels by Northern blotting, hosts received one injection of oil or E2 24 h before harvest. ER immunohistochemistry was used to monitor the completeness of tissue separation. In wt-S + wt-E tissue recombinants from E2-treated hosts, the epithelium stained intensely for LF (an abundant E2-dependent uterine secretory protein), whereas similar tissue recombinants from oil-treated hosts showed minimal immunostaining. Conversely, LF immunostaining was minimal in wt-S + ko-E grafts from both oil- and E2-treated hosts. LF staining was also minimal in ko-S + ko-E and ko-S + wt-E tissue recombinants regardless of hormone treatment. For Northern analyses, the epithelial content of the tissue recombinants was monitored using the reference epithelial transcript, E-cadherin. While all tissue recombinant groups expressed E-cadherin mRNA, wt-S + wt-E tissue recombinants from E2-treated hosts produced a strong, single 2.6-kb band of LF mRNA. LF transcripts were minimal or absent in all other tissue recombinant types. Northern blotting results identical to those seen for LF were also observed for the uterine secretory protein complement component C3. Our data demonstrate that both stromal and epithelial ER alpha are required for the production of LF protein and of LF or C3 mRNAs in response to E2. Thus, in contrast to E2-induced epithelial mitogenesis, which requires only stromal ER alpha, both epithelial and stromal ER alpha are necessary for the production of E2-dependent epithelial secretory proteins.

BiP (GRP78) and endoplasmin (GRP94) are induced following rotavirus infection and bind transiently to an endoplasmic reticulum-localized virion component

Rotavirus infection induces profound alterations in the morphology and biochemistry of the host cell. Using two-dimensional (2D) gel electrophoresis combined with metabolic labeling, we have identified four proteins that are specifically upregulated in rotavirus-infected cells. Two of these have been identified as BiP (GRP78) and endoplasmin (GRP94), members of a family of glucose-regulated chaperone proteins that reside in the endoplasmic reticulum (ER) lumen, the site of rotavirus morphogenesis. The level of mRNA and the transcriptional activity of the BiP and endoplasmin genes are increased markedly in rotavirus-infected cells, and these genes are also induced when a single rotavirus protein, the nonstructural glycoprotein NSP4, is expressed in MA104 cells. However, NSP4 does not associate with either BiP or endoplasmin, implying that the mechanism of BiP and endoplasmin gene activation by NSP4 may differ from that triggered by viral membrane glycoproteins of other viruses. The interaction of BiP and endoplasmin with rotavirus structural polypeptides suggests that these chaperones are involved in the process of viral maturation in the ER lumen.

Inactivation of the p53 tumor suppressor gene via a novel Alu rearrangement

Inactivation of the p53 tumor suppressor gene is a common finding in human cancer. In most cases, inactivation is due to a point mutation in the gene, but rearrangement of the p53 gene is sometimes observed. We analyzed the inactivation of p53 in the human pancreas cancer cell line Hs766T, which harbors a structural alteration in the p53 gene. This inactivation was found to be the result of a complex deletion/insertion event involving at least two different Alu elements. The rearrangement eliminated exons 2-4 from the p53 gene, whereas a 175-bp Alu fragment was inserted between the breakpoints of the deletion. DNA sequence analysis of this Alu fragment revealed that it is identical to an Alu element in intron 1 of the p53 gene. This is the first report of p53 inactivation due to a rearrangement involving Alu elements. This type of inactivation may go unnoticed when only traditional methods to detect p53 alterations are used.

Development and population study of an eight-locus short tandem repeat (STR) multiplex system

Amplification of short tandem repeat (STR) loci has become a useful tool for human identification applications. To improve throughput and efficiency for such uses, the polymorphic STR loci CSF1PO, TPOX, TH01, vWA, D16S539, D7S820, D13S317, D5S818, F13A01, FESFPS, F13B, and LPL have been evaluated, developed, and configured into fluorescently labeled multiplex systems. Eight of these STR loci were combined to generate the PowerPlex System, a two-color multiplex system that supports rapid, accurate, reliable analysis and designation of alleles. The remaining four loci comprise the FFFL System, a one-color multiplex system. The PowerPlex System may be evaluated alternatively as two one-color, four-locus multiplex systems, CTTv Multiplex and GammaSTR Multiplex. The products of multiplex amplification may be analyzed with a variety of fluorescence detection instruments. Determination of genotypes of over 200 individuals from each of three different population/ethnic groups revealed independence of inheritance of the loci and allowed calculation of matching probability, typical paternity index, and power of exclusion for each multiplex.

Formula supplementation with long-chain polyunsaturated fatty acids: are there developmental benefits?

OBJECTIVE

To evaluate the developmental outcomes of children who participated in an augmented randomized clinical trial of supplementing a standard infant formula with long-chain polyunsaturated fatty acids.

DESIGN

Randomized clinical trial, augmented with a nonrandomized human milk comparison group. There were three randomized formula groups: standard formula, standard formula containing docosahexaenoic acid (DHA), and standard formula containing DHA and arachidonic acid.

SETTING

Three clinical sites serving diverse populations: Kansas City, MO; Portland, OR; and Seattle, WA.

PARTICIPANTS

A total of 274 healthy full-term infants were enrolled in the infant-feeding protocol; of these, 197 (72%) participated in assessments of developmental outcome. Formula Supplements. In the randomized trial, one group received a standard formula, another group received a formula that had been supplemented with DHA from fish oil, and a third group received a formula supplemented with both DHA and arachidonic acid from an egg phospholipid.

OUTCOME MEASURES

Mental and Motor Scales of the Bayley Scales of Infant Development at 12 months of age; vocabulary and gesture communication scores from the MacArthur Communicative Development Inventories at 14 months of age.

RESULTS

There were no statistically significant differences for either the Bayley Mental Scale or the Bayley Motor Scale, neither when the analysis was restricted to the three randomized formula groups nor when the analysis included all four groups. However, the DHA formula group had significantly lower scores on two of the MacArthur scales: the DHA group scored lower than the nonrandomized human milk comparison group on the Vocabulary Comprehension Scale, and the DHA group scored lower than the randomized control formula group on the Vocabulary Production Scale. Moreover, additional analyses both in the formula groups and in the human milk comparison group found significant negative correlations between DHA levels and vocabulary outcomes.

CONCLUSION

We believe that additional research should be undertaken before the introduction of these supplements into standard infant formulas.

Estrogen receptor mutations

The purpose of this paper is to review potential novel functional pathways by which estradiol and estrogenic compounds elicit biological responses in mammals. We will limit our approach to those novel functions suggested by phenotypes associated with estrogen receptor-alpha (ER alpha) gene mutations and polymorphisms. The study of these pathways has been greatly aided by the availability of ER alpha-minus mice, which lack classic biological responses to estradiol. In addition, the availability of an ER alpha-minus human family, aromatase-minus human families, and in the near future an aromatase-minus mouse model will allow correlations of novel phenotypes with the lack of active ER alpha protein. The ER alpha-minus mice can potentially be used to characterize in depth novel clinical phenotypes that link the functions of estrogens with sexual maturation, cardiovascular disease, osteoporosis, diabetes, and cancer.

An assessment of attitudes to, and extent of, the practice of denture marking in South Australia

Denture marking or labelling is not a new concept in either prosthetic or forensic dentistry and its routine practice has been urged by forensic odontologists internationally for many years. In the general community it is often recommended for institutionalized persons to prevent confusion of ownership of dentures. In Australia, the Nursing Home Standards require that dentures of residents be 'discreetly labelled' and marking of all dentures is recommended by the Australian Dental Association. In some countries the marking of dentures is regulated by legislation, but elsewhere there seems to be a reluctance to effect this practice. Various methods which have been proposed include the insertion of an identifying label during the fabrication of the dentures with the utilization of a number of materials and coding systems. This study reports the results of a survey undertaken to determine the extent of the practice of denture marking in South Australia, the methods in use, and the attitudes of dentists, dental technicians and institutions to it. The results indicated that 24.5 per cent of all practitioners providing removable prostheses to their patients include an identifying label as part of the service on some occasions. This included 19.9 per cent of general dental practitioners, 25 per cent of specialist prosthodontists, 57.1 per cent of practitioners with training in forensic odontology, and 43.5 per cent of clinical dental technicians. No practitioner labelled dentures routinely. Reasons cited for not labelling dentures included cost, lack of awareness of standards and recommendations and a belief that it was of little importance.

Role of stromal and epithelial estrogen receptors in vaginal epithelial proliferation, stratification, and cornification

Estradiol 17-beta (E2) induces epithelial proliferation, stratification, and cornification in vaginal epithelium. Our aim was to determine the respective roles of epithelial and stromal estrogen receptor-alpha (ER alpha) in these E2-induced events. Vaginal epithelium (E) and stroma (S) from adult ER alpha knockout (ko) and wild-type (wt) neonatal Balb/c mice were enzymatically separated and used to produce four types of tissue recombinants in which epithelium, stroma, or both lack functional ER alpha. Tissue recombinants were grafted into female nude mice, which were subsequently ovariectomized and treated with oil or E2. In response to E2 treatment, grafts prepared with wt-S (wt-S + wt-E and wt-S + ko-E) showed similar large increases in epithelial labeling index, indicating that E2 stimulated epithelial proliferation despite a lack of epithelial ER alpha in wt-S + ko-E tissue recombinants. Conversely, in tissue recombinants prepared with ko-S (ko-S + wt-E and ko-S + ko-E), epithelial labeling index remained at baseline levels after E2 or oil treatment, even though epithelial ER alpha were detected in ko-S + wt-E grafts. Epithelial cornification was present in wt-S + wt-E grafts from E2-treated hosts, whereas epithelium in all other tissue recombinants failed to cornify. Grafts composed of wt-S + wt-E from E2-treated hosts had highly stratified epithelium, whereas epithelial thickness was reduced almost 60% in wt-S + ko-E tissue recombinants grown in E2-treated hosts and was atrophic in all other tissue recombinants. In addition, cytokeratin 10, a marker of epithelial differentiation, was strongly expressed in wt-S + wt-E tissue recombinants grown in E2-treated hosts but was markedly reduced or absent in all other tissue recombinants. These results indicate that E2-induced vaginal epithelial proliferation is mediated indirectly through stromal ER alpha, consistent with our recent findings in uterus. Conversely, both epithelial and stromal ER alpha are required for E2-induced cornification and normal epithelial stratification. These are the first known functions attributed to epithelial ER alpha in vivo and the first time any epithelial response to E2 has been shown to involve both stromal and epithelial ER alpha.

Approaches to study interactions between small DNA viruses and differentiated tissue

Polyomavirus (Py) derives its name from the early observation of multiple tumors that develop in newborn mice following inoculation with this family of viruses. In nature, however, tumor development is rare in the virus life cycle, rather a two-phase infection occurs, acute and persistent, resulting in a final latent infection in the kidneys. The acute phase induces an antiviral immune response, although no recognizable inflammation, which can last the lifetime of the mouse, even passing on antibodies to its offspring. The structure, replication, and expression of the Py viral genome in permissive and nonpermissive infections has been studied extensively in various cell culture systems. However, the nature of Py expression, replication, and immunopathogenesis in mice has not been thoroughly researched.

The role of N-acetylation polymorphisms in smoking-associated bladder cancer: evidence of a gene-gene-exposure three-way interaction

Arylamines are known bladder carcinogens and are an important constituent of tobacco smoke. The handling of arylamines in the body is complex and includes metabolism by NAT1 and NAT2, enzymes that play a role in both activation and detoxification of arylamines and their congeners. Both NAT1 and NAT2 are polymorphic, with alleles that have been shown to correlate with higher or lower enzyme activity. To explore the combined role of these genes and exposure on bladder cancer risk, we examined the NAT1 and NAT2 genotype in a case-control study of bladder cancer in which detailed exposure histories were available on all 230 cases and 203 frequency-matched controls. Using PCR-RFLP genotyping, we determined NAT2 genotype for the five most common alleles, NAT2*4, NAT2*5, NAT2*6, NAT2*7, NAT2*14 (frequently referred to as WT, M1, M2, M3, and M4, respectively). Similarly, the NAT1 genotype was determined for the four most common alleles NAT1*3, NAT1*4, and NAT1*11, and the putative high-activity allele, NAT1*10. No association between NAT2 genotype and bladder cancer risk was found whether genotype was considered alone or in combination with smoking, in either stratified or logistic regression analysis that adjusted for age, sex, and race. Stratified and logistic regression analysis both demonstrated an increased risk for individuals carrying the NAT1*10 allele among smokers. There was evidence of a gene-dosage effect, such that those who were homozygous for the NAT1*10 allele had the highest risks. There was also evidence of a statistically significant gene-environment interaction, such that bladder cancer risk depends on both NAT1 genotype and smoking exposure. Interestingly, although NAT2 genotype did not influence risk either alone or in combination with smoking exposure, there was evidence of a statistically significant gene-gene-environment three-way interaction. Bladder cancer risk from smoking exposure is particularly high in those who inherit NAT2 slow alleles in combination with one or two copies of the NAT1*10 allele. A biological mechanism for this finding is suggested.

Sources of referral information: a marketing analysis of physician behavior

The referral process is an important means of obtaining patients and it is necessary to determine ways of influencing the referral process to increase the patient base. This article reports research based on a survey of the referral habits of 806 primary care physicians. The results are examined in the context of physician receptivity to marketer-controlled versus health services sources of referral information.

Mechanisms underlying very-low-frequency RR-interval oscillations in humans

BACKGROUND

Survival of post-myocardial infarction patients is related inversely to their levels of very-low-frequency (0.003 to 0.03 Hz) RR-interval variability. The physiological basis for such oscillations is unclear. In our study, we used blocking drugs to evaluate potential contributions of sympathetic and vagal mechanisms and the renin-angiotensin-aldosterone system to very-low-frequency RR-interval variability in 10 young healthy subjects.

METHODS AND RESULTS

We recorded RR intervals and arterial pressures during three separate sessions, with the patient in supine and 40 degree upright tilt positions, during 20-minute frequency (0.25 Hz) and tidal volume-controlled breathing after intravenous injections: saline (control), atenolol (0.2 mg/kg, beta-adrenergic blockade), atropine sulfate (0.04 mg/kg, parasympathetic blockade), atenolol and atropine (complete autonomic blockade), and enalaprilat (0.02 mg/kg, ACE blockade). We integrated fast Fourier transform RR-interval spectral power at very low (0.003 to 0.03 Hz), low (0.05 to 0. 15 Hz), and respiratory (0.2 to 0.3 Hz) frequencies. Beta-adrenergic blockade had no significant effect on very-low- or low-frequency RR-interval power but increased respiratory frequency power 2-fold. ACE blockade had no significant effect on low or respiratory frequency RR-interval power but modestly (approximately 21%) increased very-low-frequency power in the supine (but not upright tilt) position (P<0.05). The most profound effects were exerted by parasympathetic blockade: Atropine, given alone or with atenolol, abolished nearly all RR-interval variability and decreased very-low-frequency variability by 92%.

CONCLUSIONS

Although very-low-frequency heart period rhythms are influenced by the renin-angiotensin-aldosterone system, as low and respiratory frequency RR-interval rhythms, they depend primarily on the presence of parasympathetic outflow. Therefore the prognostic value of very-low-frequency heart period oscillations may derive from the fundamental importance of parasympathetic mechanisms in cardiovascular health.

Reactions of pediatricians to the recommendation for universal varicella vaccination

OBJECTIVES

To determine the rate of self-reported adherence by pediatricians to the 1995 American Academy of Pediatrics and the Advisory Committee on Immunization Practices varicella immunization recommendations and to evaluate factors that might influence adherence.

DESIGN

Mail survey.

SETTING AND PARTICIPANTS

Washington State pediatricians.

MAIN OUTCOME MEASURE

Logistic regression was used to identify demographic characteristics, attitudes about varicella vaccine, and previous experiences with the disease that were associated with self-reported adherence to universal varicella immunization recommendations.

RESULTS

Completed surveys were returned by 76% of contacted pediatricians, of whom 42% reported following a policy of universal varicella immunization. In multivariate analysis, agreement with statements regarding the effectiveness of varicella vaccine in reducing rare but serious complications of the disease (odds ratio [OR], 4.90; 95% confidence interval [CI], 2.30-10.50) and in decreasing work loss by parents (OR, 4.21; 95% CI, 1.14-15.50) were associated with recommending universal immunization. Disagreement with statements concerning the lack of the need for varicella immunization because complications are rare (OR, 2.54; 95% CI, 1.12-5.74), it is not required for school entry (OR, 2.52; 95% CI, 1.37-4.64), and it is not medically cost-effective (OR, 2.25; 95% CI, 1.21-4.18) were also associated with universally recommending the vaccine. In addition, experience with varicella encephalitis was also associated with adherence to the recommendations (OR, 1.96; 95% CI, 1.06-3.65). Conversely, those who were concerned that varicella vaccine might not provide lifelong immunity were less likely to report recommending universal vaccination (OR, 0.36; 95% CI, 0.19-0.68).

CONCLUSIONS

Fewer than 50% of responding Washington State pediatricians reported recommending universal varicella vaccination. Adherence to the recommendations appears to be influenced by personal experience, perceptions about the potential seriousness of varicella, and beliefs about the societal and medical cost-effectiveness of varicella vaccine.

Transcription and translation of estrogen receptor-beta in the male reproductive tract of estrogen receptor-alpha knock-out and wild-type mice

Estrogen receptor-alpha (ERalpha) has been identified in the male reproductive tract, but the role of estrogen in the male has not been well characterized. In vivo mutations in ERalpha genes have demonstrated the necessity for ERalpha-mediated action in male fertility. We asked whether both ERbeta messenger RNA and protein were present in the male reproductive tract of wild-type and ERalpha knock-out (ERalpha KO) mice, and whether ERbeta could compensate for the lack of ERalpha in infertile male ERalpha KO mice. Immunohistochemical localization with both N- and C-terminal anti-ERbeta antibodies demonstrated that ERbeta is present in the Leydig cells of the testes and in the epithelium of both the efferent ductules and the initial segment of the epididymis. RT-PCR amplification was used to confirm ERbeta transcription in these tissues. In conclusion, we observed that ERbeta messenger RNA and protein continue to be expressed in the Leydig cells, elongated spermatids, efferent ductules, and the initial segment of the epididymides of ERalpha KO mice, but the presence of ERbeta is not able to compensate for the absence of ERalpha in male reproductive function.

Group well-child care for high-risk families: maternal outcomes

OBJECTIVE

To determine if participation in group sessions as part of health supervision visits for infants improves outcomes compared with individual visits in high-risk mothers.

STUDY DESIGN

Randomized controlled clinical trial.

PARTICIPANTS

Mothers of young infants who had at least 1 of the following risk factors: aged younger than 20 years at delivery, participation in Medicaid, less than a high school education, previous or ongoing substance abuse, or history of abuse as a child.

SETTING

Two urban university pediatric clinics in Seattle, Wash.

INTERVENTIONS

Mother-infant dyads were randomized to receive group well-child care (GWCC) or individual well-child care (IWCC) before the infant was 4 months old; the intervention continued until the child was 15 months old. Mothers completed the Sense of Competence and Social Isolation subscales from the Parenting Stress Index and Sarason's Social Support Questionnaire at enrollment and again on completion of the study. During the 11-month study period, 7 health supervision visits were scheduled for each mother-infant dyad. Social workers met periodically with mothers during the study and assessed the following functional outcomes: return to school, return to work, enrollment in a substance abuse treatment program, and becoming pregnant. In addition, data on study children were collected from Child Protective Services to assess referrals because of suspected abuse and/or neglect.

RESULTS

Data were collected on 213 mother-infant dyads, including 108 who received GWCC and 105 who received IWCC. At the conclusion of the study period, similar proportions of GWCC and IWCC mothers scored in the high-risk range on the Sense of Competence subscale, Social Isolation subscale, and the Social Support Questionnaire (P=.57, .32, and .59, respectively). For more than 50% of the mothers, scores on the Sense of Competence and Social Isolation subscales deteriorated during the study period from the not-high-risk range to the high-risk range, regardless of assignment to GWCC or IWCC. No differences were noted between GWCC and IWCC mothers for any functional outcome. During the study period, 8.8% of children receiving GWCC were referred to Child Protective Services vs 8.3% of those receiving IWCC (P=.85).

CONCLUSION

The format of well-child care may not be an important determinant of outcomes among high-risk mothers.

Posterior limbus fractures: five case reports and a review of selected published cases

OBJECTIVE

To discuss the clinical presentation of posterior limbus fractures and present a review of the literature on this topic.

CLINICAL FEATURES

Patients presented with a combination of lower back pain, muscle spasm, diminished reflex responses, restricted motion and foot drop. In some cases, onset followed trauma; in others, it did not.

INTERVENTION AND OUTCOME

Some patients required surgical intervention, whereas others underwent chiropractic manipulation and other conservative interventions.

CONCLUSION

Posterior limbus fractures represent an avulsion of the ring apophysis from the vertebral body. Appropriate diagnostic work-up can help determine the presence of this condition. Management considerations are discussed.

Low-frequency arterial pressure fluctuations do not reflect sympathetic outflow: gender and age differences

Low-frequency arterial pressure oscillations (Mayer waves) have been proposed as an index of vascular sympathetic outflow. However, cross-sectional differences in these pressure oscillations may not reflect different levels of sympathetic nervous outflow in humans. Three groups of healthy subjects with characteristically different sympathetic nervous outflow were studied: young females (n = 10, 18-28 yr), young males (n = 11, 18-29 yr), and older males (n = 13, 60-72 yr). Average R-R interval, arterial pressures, and systolic pressure variability at the Mayer wave frequency (0.05-0.15 Hz) did not differ among the three groups. Diastolic pressure Mayer wave variability was similar in young females vs. young males (39 +/- 10 vs. 34 +/- 5 mmHg2) and lower in older males vs. young males (14 +/- 2 mmHg2; P < 0.05). In contrast, muscle sympathetic activity was lowest in young females (892 +/- 249 total activity/min) and highest in older males (3,616 +/- 528 total activity/min; both P < 0.05 vs. young males: 2,505 +/- 285 total activity/min). Across the three groups, arterial pressure Mayer wave variability did not correlate with any index of sympathetic activity. Our results demonstrate that arterial pressure Mayer wave amplitude is not a surrogate measure of vascular sympathetic outflow.

Prevalence of clinical sinusitis in young children followed up by primary care pediatricians

OBJECTIVE

To determine the proportion of young children seen in primary care pediatric practices who meet clinical criteria for the diagnosis of sinusitis, and variations in the management of these patients' conditions.

DESIGN

Observational cohort study.

SETTINGS

Pediatric practices in the Seattle, Wash, area participating in the Puget Sound Pediatric Research Network, a regional practice-based research organization.

PATIENTS

Children, 1 to 5 years old, presenting for any reason to participating practices.

METHODS

Parents of all 1307 eligible children completed a survey specifically detailing the presence of nasal congestion or discharge and daytime cough, the duration of these symptoms, and whether the symptoms were improving. For patients meeting clinical criteria for sinusitis (nasal congestion and daytime cough persisting for > 9 days without improvement), the pediatrician recorded the presence/severity of other signs and symptoms, and the treatment prescribed. Severity of symptoms was reassessed using telephone interviews with parents at 48 to 72 hours, and again at 10 to 14 days, after the office visit. Study data were collected during 1-week to 3-week blocks at each office site during the winter months.

RESULTS

Data were collected on 1307 children; 121 had persistent respiratory symptoms meeting criteria for a diagnosis of sinusitis (9.3%, 95% confidence interval, 7.7%-10.9%). Patients who presented with cold/cough symptoms were significantly more likely to meet criteria for sinusitis than those who came for any other reason (17.3% vs 4.2%, respectively, P < .001). A physician study form was completed on 87 children with persistent symptoms; antibiotics were prescribed for 68 (78%) of these patients. Antibiotic-treated patients were more likely to have symptoms lasting longer than 29 days (P = .004) and to have purulent nasal discharge (P = .03), and were judged to be sicker at enrollment (P = .001) than untreated children. A concurrent otitis media was diagnosed in 40 (46%) of 87 patients; if the proportion of children with otitis media is excluded, 5% of children 1 to 5 years old who are seen in primary care pediatrics might be expected to receive antibiotics exclusively for a diagnosis of sinusitis. At 24 to 48 hours and at 10 to 14 days after the clinic visit, a trend was noted toward more rapid improvement among those children who were treated with antibiotics.

CONCLUSION

When the criteria are strictly adhered to, only a small proportion of young children seen during the winter months in primary care pediatric practices will be diagnosed with sinusitis.

Controlled breathing protocols probe human autonomic cardiovascular rhythms

The purpose of this study was to determine how breathing protocols requiring varying degrees of control affect cardiovascular dynamics. We measured inspiratory volume, end-tidal CO2, R-R interval, and arterial pressure spectral power in 10 volunteers who followed the following 5 breathing protocols: 1) uncontrolled breathing for 5 min; 2) stepwise frequency breathing (at 0.3, 0.25, 0.2, 0.15, 0.1, and 0.05 Hz for 2 min each); 3) stepwise frequency breathing as above, but with prescribed tidal volumes; 4) random-frequency breathing (approximately 0.5-0.05 Hz) for 6 min; and 5) fixed-frequency breathing (0.25 Hz) for 5 min. During stepwise breathing, R-R interval and arterial pressure spectral power increased as breathing frequency decreased. Control of inspired volume reduced R-R interval spectral power during 0.1 Hz breathing (P < 0.05). Stepwise and random-breathing protocols yielded comparable coherence and transfer functions between respiration and R-R intervals and systolic pressure and R-R intervals. Random- and fixed-frequency breathing reduced end-tidal CO2 modestly (P < 0.05). Our data suggest that stringent tidal volume control attenuates low-frequency R-R interval oscillations and that fixed- and random-rate breathing may decrease CO2 chemoreceptor stimulation. We conclude that autonomic rhythms measured during different breathing protocols have much in common but that a stepwise protocol without stringent control of inspired volume may allow for the most efficient assessment of short-term respiratory-mediated autonomic oscillations.