Recently discharged inpatients as a source of emergency department overcrowding.

OBJECTIVE: To assess the impact on the emergency department (ED) of recently discharged inpatients and how they contribute to and worsen the current situation of ED overcrowding. METHODS: Retrospective, observational study of medical records and billing data of all patients presenting to the ED within seven days of inpatient discharge from the hospital ("returns") in September 2000. The data were collected from electronic logs. Billing charges were used to estimate ED resources. Medical records were reviewed to classify visits: 1) new problem, 2) related problem, likely preventable, 3) related problem, not likely preventable, 4) unable to classify, or 5) incomplete chart. RESULTS: One-hundred seventy-four returns occurred among 6,290 total ED visits (3%). Significant differences between returns and total ED patients were noted for length of stay (LOS) (6.58 vs 5.22 hours, p = 0.000), percent admitted (47% vs 19%, p = 0.000), and ED billing (1,415.67 dollars vs 391.00 dollars, p = 0.000). The highest rate of admission was for patients presenting 48-72 hours after inpatient discharge (65.4%). Admission rate was higher for patients presenting >48 hours than <48 hours (54% vs 33%, p = 0.01). A review of the medical records (117/174) revealed: 15 new problems (13%); 16 related, likely preventable (14%); 72 related, not likely preventable (62%); 4 unable to assess (2%); and 10 incomplete charts (9%). CONCLUSIONS: The ED is appropriately utilized as a safety net for discharged inpatients. Though "returns" are a small percentage of ED patients, they have longer LOSs, have higher ED charges, and are more frequently admitted. Returns increase the strain on an already overcrowded ED.

Pediatric cervical spine injury sustained in falls from low heights.

STUDY OBJECTIVE: To determine whether history and clinical examination findings can identify young children who have sustained cervical injury after falling short distances. METHODS: We conducted a retrospective review of the medical records of children younger than 6 years old with the diagnosis of cervical vertebral fracture or cervical spinal cord injury after a fall of less than 5 feet. Data from medical records over an average time span of 11 years at four large children's hospitals were compiled. RESULTS: We identified eight children who sustained cervical spine injury after a fall of less than 5 feet. These children ranged in age from 9 to 68 months. Three had rotary subluxation of C1, and three had subluxation of C1-C2. One of the children in the latter group also had an odontoid fracture. Two children had a fracture of C2. All the children had limited range of motion of the neck or neck pain. CONCLUSION: All children in this study with the diagnosis of cervical spine injury had clinical evidence of that injury on history or physical examination. Clinicians treating asymptomatic young children who sustain short falls may not need to perform radiographic evaluation of the cervical spine.

Baseball injuries: a Little League survey.

OBJECTIVES: To determine the patterns of injury in youth baseball and apply the data to estimate the value of proposed safety equipment. DESIGN: Prospective population-based injury survey. PARTICIPANTS: 2861 Little League baseball players (ages 7 to 18) for 140 932 player-hours. MEASUREMENTS: An injury was included in the data only if it was serious enough to require medical/dental care, caused missing a game, or disallowed playing a certain position. The injuries were subdivided into acute or overuse. The acute injuries were classified as either catastrophic, severe, or minor. Injuries were categorized according to mechanism, area injured, and whether the player was on offense or defense. RESULTS: There were 81 total injuries, of which 66 (81%) were acute and 15 (19%) were overuse. Of the acute injuries, 11 were severe and 55 were minor. The overall injury rate was .057 injuries per 100 player-hours. The severe injury rate was .008 injuries per 100 player-hours, of which 46% were ball-related injuries and 27% were collisions. The most frequent mechanism of injury was being hit by the ball, which represented 62% of the acute injuries. Of the 41 ball-related injuries, 28 (68%) occurred to players on defense. Of the 18 ball-related facial injuries, 16 occurred to players on defense. CONCLUSIONS: 1) Little League baseball is a safe activity with a low injury rate and a particularly low rate of severe injury; 2) impact by the ball causes more than half the acute injuries, thus safety interventions should be directed towards decreasing these injuries, especially on defense; and 3) facemasks on batters can safely eliminate facial injuries to offensive players, but would only moderately reduce the incidence of ball-related facial injuries as most of these injuries are sustained by defensive players.

Developing prediction rules and evaluating observation patterns using categorical clinical markers: two complementary procedures.

Substantial uncertainty often remains at the time that important diagnostic or therapeutic decisions must be made, despite the availability of multiple clinical indicators. Multiple indicators may be used to define observation patterns that are associated with the presence or absence of disease. Clinical prediction rules based on groups of observation patterns have been used to quantify probabilities and reduce error rates for some medical problems, but efficient use of multiple indicators remains a major challenge in medical practice. Medical outcomes and clinical observations are frequently categorical. Two statistical techniques appropriate for generating prediction rules from categorical data are logit analysis (LA) and recursive partitioning analysis (RPA). LA and RPA were compared in evaluating observation patterns for fractures among 666 upper-extremity injuries in children, and in developing prediction rules for selective radiographic assessment. Fracture estimates and error reductions provided by RPA and LA were very similar. Each technique generated a set of prediction rules with a range of misclassification probabilities, and evaluated the probabilities of fracture for all observation patterns. LA used more information than RPA in observation pattern evaluations, however, and provided fracture estimates specific to each pattern. With currently available statistical software, RPA output provides better statistical guidance in generating prediction rules, whereas LA provides more statistical information of use in evaluating observation patterns. LA warrants attention similar to that conferred on RPA. It appears that complementary use of LA and RPA would be valuable in developing clinical guidelines.

Alzheimer's disease and control brain contain soluble derivatives of the amyloid protein precursor that end within the beta amyloid protein region.

The 39-43 amino acid beta amyloid protein (A beta) that deposits as amyloid in the brains of patients with Alzheimer's disease (AD) is encoded as an internal sequence within a larger membrane-associated protein known as the amyloid protein precursor (APP). In cultured cells, the APP is normally cleaved within the A beta to generate a large secreted derivative and a small membrane-associated fragment. Neither of these derivatives can produce amyloid because neither contains the entire A beta. Our study was designed to determine whether the soluble APP derivatives in human brain end within the A beta as described in cell culture or whether AD brain produces potentially amyloidogenic soluble derivatives that contain the entire A beta. We find that both AD and control brain contain nonamyloidogenic soluble derivatives that end at position 15 of the A beta. We have been unable to detect any soluble derivatives that contain the entire A beta in either the AD or control brain.

Alzheimer's amyloid precursor protein produced by recombinant baculovirus expression. Proteolytic processing and protease inhibitory properties.

The baculovirus expression system was used to generate recombinant Alzheimer's amyloid precursor (AAP) proteins. Recombinant baculoviruses were constructed, designed to express full-length 695-, 751-, and 770-amino acid forms. Recombinant baculoviruses designed for constitutive secretion were engineered by placing a termination codon between the beta-protein domain and cytoplasmic anchor of the full-length forms. Insect cells infected with each of these baculoviruses produced both secreted and cell-associated AAPs. Full-length constructs produced secreted derivatives which were COOH-terminally cleaved within the beta-protein domain at Gln15 or Lys16, essentially identical to previous reports utilizing mammalian cell systems. Rare secreted forms (less than 5%) appeared to extend to Lys28. Secretion constructs produced these same forms, but in different ratios. Most (approximately 60%) terminated at Gln15 or Lys16, while the remainder apparently extended to Lys28. AAPs containing the Kunitz-type serine protease inhibitory domain (AAP-751 and -770) were shown to be active inhibitors. No differences were observed in the inhibitors activities of these two forms. The similarities in AAP processing by insect and mammalian systems, together with the large amounts of recombinant protein produced by baculovirus expression, make this an attractive system for studies of AAP processing and biochemical properties.

Prediction rules for selective radiographic assessment of extremity injuries in children and adolescents.

To assess the potential for selective use of roentgenography in evaluating extremity injuries, prediction rules were developed based on prospective observations for 617 injured children and adolescents examined in our Emergency Department (phase 1) and tested on 601 examined 1 year later (phase 2). Logit analysis produced best-fitting statistical models for phase 1 data with significant (P less than 0.05) direct effects of gross signs, point tenderness, activity not routine, swelling moderate or severe, time from injury less than 6 hours, and pain with motion for upper extremity injuries; and, for lower extremity injuries, not knee injury, activity not routine, point tenderness, and foot injury. Prediction rules developed in phase 1 performed equally well when tested on phase 2 injuries. Data from both phases were combined, therefore, in analysis that produced risk estimates. For all injury types (ie, for injuries with all possible combinations of presence or absence of these findings), risk for fracture was derived. For upper extremity injuries, with a threshold risk for fracture of 20% used to select specific injury types for roentgenography, prediction rule outcomes were 18.1% of roentgenograms avoided and 5.3% of fractures missed. For lower extremity injuries, using a threshold risk of 10% to select injury types for roentgenography, outcomes were 25.8% of roentgenograms avoided and 5.3% of fractures missed. Alternative prediction rules allowed still greater roentgenogram avoidance, although missed fractures also increased. Risk of adverse functional outcome from missed fractures appeared small. Annual national cost savings from the elimination of 18.1% of upper and 25.8% of lower extremity roentgenographic evaluations was estimated at $103 million.

Astrocytes in Alzheimer's disease gray matter express alpha 1-antichymotrypsin mRNA.

The serine protease inhibitor alpha 1-antichymotrypsin (ACT) has been shown to be tightly associated with the amyloid found in plaque cores and blood vessels in the brains of patients with Alzheimer's disease (AD). Although the ACT found in plaques could be derived from the high levels of ACT in serum, previous Northern analysis revealed that ACT mRNA is produced locally in AD gray matter at much higher levels than in control gray matter. To determine which brain cells express ACT mRNA, we conducted in situ hybridization with 35S-labeled cRNA probes on hippocampal sections from four AD and three control cases. To identify astrocytes unequivocally, some of the hybridized sections were immunostained for glial fibrillary acidic protein, which is astrocyte-specific. Our results showed numerous astrocytes that were intensely labeled by the probe for ACT mRNA throughout the subicular gray matter of the AD cases. In contrast, astrocytes in control gray matter were rarely labeled by the probe for ACT mRNA. Examination of plaque cores in the AD subiculum showed that some astrocytes intensely labeled by the probe for ACT mRNA were closely associated with virtually every plaque core. Our results also showed many astrocytes in both AD and control white matter that were intensely labeled by the probe for ACT mRNA, and a small fraction of the astrocytes in a juvenile cerebellar astrocytoma that we examined were found to produce high levels of ACT mRNA. In every area in which astrocytes expressing ACT mRNA were found, astrocytes producing no detectable ACT message were also present. Our findings indicate that astrocytes produce the increased ACT mRNA in AD gray matter observed by Northern analysis, but they also show that ACT mRNA expression by astrocytes is not unique to AD. The presence of astrocytes expressing ACT mRNA near, and extending processes towards, plaque cores strongly suggests that some if not all of the ACT associated with amyloid plaque cores is produced by astrocytes surrounding the cores.

Behavioral and sociocognitive correlates of ratings of prosocial behavior and sociometric status.

Although peers' and teachers' evaluations of children's prosocial behavior and peers' sociometric ratings frequently have been used in studies of social development, the validity of young children's ratings of others has been questioned, as has that for teachers' ratings of prosocial behavior. In this study, preschoolers' ratings of peers' sociometric status and prosocial behavior, as well as teachers' ratings of children's prosocial dispositions, were obtained. These were correlated with children's naturally occurring prosocial or social behavior; ratings of prosocial behavior also were correlated with children's prosocial moral reasoning and prosocial self-attributions. Peers' sociometric ratings were positively related to children's sociability whereas prosocial ratings were related to helping (but not sharing) behavior. Teachers' ratings of prosocial behavior were not related to frequency of prosocial behaviors, but were positively related to developmentally mature moral judgments and self-reported motives.

Catalysis of the disproportionation of superoxide by metalloporphyrins. III.

An assay based on the use of an oxygen electrode has been used to determine the superoxide dismutase-type activity of several metalloporphyrins. Both the iron(III) and manganese(III) derivatives of tetrakis-(4-N-methylpyridyl)porphine were shown to have comparable activity, about 2-3% of that of the enzyme. Comparisons are made between this assay method and the more standard one which depends on the conversion of nitroblue tetrazolium to formazan.