Comparing Boston naming test short forms in a rehabilitation sample.

The Boston Naming Test (BNT) has multiple short forms that do not include the noose item that have been primarily examined in dementia populations. This study compared BNT short forms with standard administration (BNT-S) in physical medicine and rehabilitation patients who underwent outpatient evaluation. The sample (N = 480) was 34% female and 91% white with average age of 46 years (SD = 15) and average education of 14 years (SD = 3). Five 15-item short forms were calculated: Consortium to Establish a Registry for Alzheimer's disease (CERAD-15); Lansing; and Mack 1, 2, and 4 (Mack-15.1, -15.2). Three 30-item short forms were calculated: Mack A, Saxon A, and BNT odd items. BNT-S and short forms were compared with Spearman correlations. Cronbach's alpha was calculated for all BNT forms. Impaired BNT scores were determined with norm-referenced scores (T < 36 and T < 40). Area under the curve (AUC) values were compared across short forms with impaired BNT as criterion. BNT-S showed strong correlations with 30-item (rho = 0.92-0.93) and 15-item short forms (rho = 0.80-0.87) except for CERAD-15 (rho = 0.69). Internal consistency was acceptable for all short forms (alpha = 0.72-0.86). BNT-S was impaired in 17% and 33% of participants at 35 T and 39 T cutoffs, respectively. BNT short forms showed excellent to outstanding classification accuracy predicting impairment using both cutoffs. BNT short forms warrant further study in rehabilitation settings.

Psychometric Equivalence of Standard and Prorated Boston Naming Test Scores.

This study compared prorated Boston Naming Test (BNT-P; omitting the noose item) and standard administration (BNT-S) scores in physical medicine and rehabilitation patients (N = 480). The sample was 34% female and 91% White with average age and education of 46 (SD = 15) and 14 (SD = 3) years, respectively. BNT-P was calculated by summing correct responses excluding item 48 and estimating the 60-item score with cross multiplication and division. BNT-P and BNT-S scores were compared via concordance correlation (CC) coefficients; reflected and log transformed data were examined with equivalence tests. BNT-P and BNT-S scores showed almost perfect agreement (CC = .99). Transformed scores demonstrated equivalence (±1.1 points). Raw and scaled score differences were 0 in 88% and 96% of cases, respectively. Race and ethnicity accounted for item 48 outcomes while controlling for age and education. Findings support the utility of prorated BNT scores in rehabilitation patients.

Catecholamine-resistant hypotension and myocardial performance following patent ductus arteriosus ligation.

OBJECTIVE: We performed a multicenter study of preterm infants, who were about to undergo patent ductus arteriosus ligation, to determine whether echocardiographic indices of impaired myocardial performance were associated with subsequent development of catecholamine-resistant hypotension following ligation. STUDY DESIGN: A standardized treatment approach for hypotension was followed at each center. Infants were considered to have catecholamine-resistant hypotension if their dopamine infusion was > 15 µg kg(-1)min(-1). Echocardiograms and cortisol measurements were obtained between 6 and 14 h after the ligation (prior to the presence of catecholamine-resistant hypotension). RESULT: Forty-five infants were enrolled, 10 received catecholamines (6 were catecholamine-responsive and 4 developed catecholamine-resistant hypotension). Catecholamine-resistant hypotension was not associated with decreased preload, shortening fraction or ventricular output. Infants with catecholamine-resistant hypotension had significantly lower levels of systemic vascular resistance and postoperative cortisol concentration. CONCLUSION: We speculate that low cortisol levels and impaired vascular tone may have a more important role than impaired cardiac performance in post-ligation catecholamine-resistant hypotension.

Abnormal heart rate characteristics before clinical diagnosis of necrotizing enterocolitis.

OBJECTIVE: Earlier diagnosis and treatment of necrotizing enterocolitis (NEC) in preterm infants, before clinical deterioration, might improve outcomes. A monitor that measures abnormal heart rate characteristics (HRC) of decreased variability and transient decelerations was developed as an early warning system for sepsis. As NEC shares pathophysiologic features with sepsis, we tested the hypothesis that abnormal HRC occur before clinical diagnosis of NEC. STUDY DESIGN: Retrospective review of Bells stage II to III NEC cases among infants <34 weeks gestation enrolled in a prospective randomized clinical trial of HRC monitoring at three neonatal intensive care units. RESULT: Of 97 infants with NEC and HRC data, 33 underwent surgical intervention within 1 week of diagnosis. The baseline HRC index from 1 to 3 days before diagnosis was higher in patients who developed surgical vs medical NEC (2.06±1.98 vs 1.22±1.10, P=0.009). The HRC index increased significantly 16 h before the clinical diagnosis of surgical NEC and 6 h before medical NEC. At the time of clinical diagnosis, the HRC index was higher in patients with surgical vs medical NEC (3.3±2.2 vs 1.9±1.7, P<0.001). CONCLUSION: Abnormal HRC occur before clinical diagnosis of NEC, suggesting that continuous HRC monitoring may facilitate earlier detection and treatment.

B-type natriuretic peptide concentrations to guide treatment of patent ductus arteriosus.

OBJECTIVE: To determine whether b-type natriuretic peptide (BNP) concentrations can guide treatment of patent ductus arteriosus (PDA) to reduce the number of indomethacin doses without increasing morbidity. DESIGN: Prospective, randomised, controlled trial. SETTING: Single-centre referral neonatal intensive care unit. PATIENTS: Infants with echocardiographic diagnosis of PDA. Infants with congenital heart disease or renal insufficiency were excluded. INTERVENTIONS: BNP measurement and echocardiography were performed in all subjects before and after indomethacin treatment. The investigational group had BNP concentrations measured 12 and 24 h after the first dose (before the 2nd and 3rd doses of indomethacin). Indomethacin dosing was withheld in the BNP-guided group if the 12 or 24 h BNP concentrations were found to be <100 pg/ml. MAIN OUTCOME MEASURES: Number of doses of indomethacin given during the primary course of treatment (three doses every 12 h). RESULTS: Sixty patients were randomly assigned to control (n = 30) and BNP-guided (n = 30) treatment groups. There was no difference between the groups with respect to gestational age (26(+3) vs 25(+5) weeks, respectively), Apgar scores, delivery method, gender or indomethacin prophylaxis. Median baseline and 48 h BNP concentrations did not differ between the groups (0 h: 500 vs 542 pg/ml; 48 h: 85 vs 126 pg/ml; control and BNP-guided groups, respectively). During primary indomethacin treatment, the BNP-guided group received fewer doses of indomethacin than controls (70 vs 88 doses, p<0.05). The rate of PDA ligation, intestinal perforation and chronic lung disease did not differ between groups. CONCLUSIONS: BNP-guided treatment reduced the number of primary indomethacin doses. There was no increase in PDA persistence or associated morbidity.

Emerging trends in acquired neonatal intestinal disease: is it time to abandon Bell's criteria?

In the last decade, it has become increasingly clear that necrotizing enterocolitis (NEC) is neither a uniform nor a well-defined disease entity. There are many factors that are forcing this unwelcome realization upon the neonatal and pediatric surgery communities. In the course of this manuscript we will review the history and the physical findings of the disparate etiologies of acquired neonatal intestinal diseases (ANIDs), some which do lead to the common final pathology of NEC and some which do not. New guidelines for distinguishing between ANIDs will also be suggested.

New insights into spontaneous intestinal perforation using a national data set (3): antenatal steroids have no adverse association with spontaneous intestinal perforation.

OBJECTIVE: To examine whether antenatal steroids (ANS), alone or with early indomethacin, are associated with spontaneous intestinal perforation (SIP). SIP is a known complication of concurrent post-natal administration of glucocorticoid and indomethacin in extremely low birth weight (ELBW) infants. STUDY DESIGN: A large de-identified national data set was retrospectively examined for infants with SIP without any report of other malformation or necrotizing entrocolitis. A control group was then derived matching for gender and birth weight (+/- 20 g). Pre- and post-natal variables were tested by both univariate and multivariate analysis to identify associations with SIP. RESULTS: From January 1996 to June 2004, there were 2 27 711 discharges from Pediatrix neonatal intensive care unit sites. From this population 388 infants with SIP associated with ELBW were compared to matched controls. Infants with SIP were more likely to have received early indomethacin and to have received a combination of early indomethacin with post-natal glucocorticoids (P < 0.05 for both). When used alone (without subsequent indomethacin), ANS showed no association with SIP. When used in conjunction with indomethacin, ANS did not increase the rate of SIP beyond indomethacin alone. CONCLUSION: ELBW Infants that acquire SIP were more likely to have been exposed to early indomethacin and post-natal glucocorticoids. However, no association was found between SIP and ANS within a well-powered cohort.

AMPA-induced excitotoxicity increases nuclear levels of CAD, endonuclease G, and acinus and induces chromatin condensation in rat hippocampal pyramidal neurons.

Programmed cell death has been linked to AMPA-receptor-mediated excitotoxicity in pyramidal neurons of the hippocampus. The intent of this study was to investigate the roles of caspase-dependent and independent nuclear death-related factors in mediating AMPA-induced nuclear changes in PyNs by use of immunohistochemistry and transmission electron microscopy (TEM). Data indicate increases in the nuclear levels of caspase-activated acinus and DNase and Endonuclease G (a caspase-independent endonuclease) in CA1 and CA3 PyN nuclei with different temporal patterns following an AMPA-insult. Hoechst staining and TEM confirm AMPA-induced chromatin condensation. The presence of active acinus in nuclei suggests it mediates chromatin condensation. Interestingly, a DNA fragmentation labeling protocol showed that there was no chromatin cleavage up to 90 min after AMPA-insult. Overall, we conclude that: 1) AMPA-induced excitotoxicity increases nuclear immunoreactivity of pro-death enzymes from multiple programmed cell death pathways, 2) differential chromatin condensation patterns occur between CA1 and CA3, and 3) there is no chromatin cleavage within our experimental timeframe.

New insights into spontaneous intestinal perforation using a national data set: (2) two populations of patients with perforations.

BACKGROUND: Spontaneous intestinal perforation (SIP) is increasingly common in the premature infant and has been demonstrated to be associated with early postnatal administration of glucocorticoids and indomethacin. Before survival of the extremely low birth weight (ELBW) infant, SIP was thought to be a rare, congenitally acquired disease sporadically affecting the muscularis of the distal intestine. These disparate views of etiology have not been previously reconciled in the literature. OBJECTIVES: (1) To establish a cohort of SIP patients in a national data set. (2) To use timing of diagnosis as a unique data element and thereby differentiate between SIP cases which are susceptible to postnatal risk factors versus those occurring at or immediately after birth (and therefore not exposed to postnatal risk factors). METHODS: A large identified national data set was used to retrospectively look at timing of diagnosis and then the cohort was divided into postnatal treatment groups for further subanalyses. This analysis resulted in the division of the cohort into early and late diagnosis SIP subcohorts. These were then queried retrospectively by univariate analysis to look for differences in demographics between the two (using a P-value < 0.05). RESULTS: There were 633 patients with SIP evaluated in this data set. The early SIP cohort (0-3 days) was made up of 116 infants with a median BW of 1.401 kg, whereas the late cohort (4-14 days) held 386 infants with a median BW of 775 g. Infants with early SIP were significantly more likely to: be male, have higher Apgar scores, have not received antenatal steroids, surfactant or required mechanical ventilation. CONCLUSIONS: Two populations of infants acquire SIP: ELBW infants acquire SIP on average between 7 and 10 days of life after exposure to indomethacin and glucocorticoids (either endogenous or exogenous), and infants with early SIP (0-3 days) who are significantly less likely to have been exposed to postnatal risk factors and are less premature.

New insights into spontaneous intestinal perforation using a national data set: (1) SIP is associated with early indomethacin exposure.

BACKGROUND: Spontaneous intestinal perforation (SIP) is increasingly common in the premature infant and is associated with significant morbidity. Indomethacin use has been implicated as a co-risk factor for SIP when combined with glucocorticoids, but previous evidence argued against indomethacin being an independent risk factor when used prophylactically. OBJECTIVES: (1) To establish a homogeneous cohort of SIP patients in a national data set and to contrast them to patients with surgical necrotizing enterocolitis (NEC). (2) To test the hypothesis that early post-natal indomethacin is independently associated with SIP. METHODS: A large de-identified data set was retrospectively queried by diagnosis, and then multiple antenatal and post-natal variables were tested by both univariate and multivariate analysis to identify associations with SIP. Sub-analyses were also performed to look at the timing of drug administration. RESULTS: There were 2105 patients evaluated in the data set. Patients were divided into matched controls (n = 581), those with SIP without report of NEC (n = 633) and those with NEC requiring surgery (n = 891). Infants with SIP were more likely to have a patent ductus arteriosus and more likely to be treated with vasopressors than either control or NEC patients. Compared to infants with NEC, patients with SIP were smaller, less mature and required more support. SIP was also diagnosed earlier than NEC (median of 7 vs 15 days). Patients with SIP were more likely to be treated with indomethacin, hydrocortisone or both on days of life 0-3 than controls. CONCLUSIONS: (1) Surgical NEC and SIP have significant differences in presentation, demographics and morbidity. (2) A detailed look at drug timing revealed that early post-natal indomethacin is independently associated with SIP.

Discharge outcomes of extremely low birth weight infants with spontaneous intestinal perforations.

OBJECTIVE: To examine discharge outcomes of extremely low birth weight infants (ELBW) with spontaneous intestinal perforation (SIP). STUDY DESIGN: A single-center retrospective cohort study of all ELBW infants admitted to the University of Virginia neonatal intensive care unit between July 1996 and June 2004. RESULTS: We found 35 patients with SIP (incidence 8.4%). The median gestational age was 25 weeks, median birth weight was 722 g, and 71% of the infants were male. Most infants (n=28) with SIP were diagnosed secondary to pneumoperitoneum; however, one-third (7) of infants<25 weeks had occult presentations without pneumoperitoneum. When controlled for gestational age, gender, multiple gestation, indomethacin, and glucocorticoid exposure, infants with SIP have a higher risk of PVL and death than infants without perforation. SUMMARY: Periventricular leukomalacia and death are significantly associated with SIP in ELBW after adjusting for gestational age, multiple gestation, indomethacin, and glucocorticoid exposure.

An assay for human chorionic gonadotrophin using the capillary fill immunosensor.

Recently there has been much research effort directed towards the development of immunosensors. Optical technologies are currently proving very attractive for the construction of such sensors. The fluorescence capillary fill device (FCFD) has been designed to fulfil these needs. The development of an assay for human chorionic gonadotrophin (hCG) in the FCFD for a variety of body fluids (whole blood, serum, urine and saliva) demonstrates the versatility and assay performance of the device.

Sensitivity enhancement of optical immunosensors by the use of a surface plasmon resonance fluoroimmunoassay.

Optical immunosensors employing evanescent wave techniques have the potential to address the requirements of the 'alternative site' market; however, this potential has yet to be realised. The development of 'direct' sensors, such as those using surface plasmon resonance (SPR), has been hampered by problems of non-specific binding and poor sensitivity to small molecules. 'Indirect' sensors (for example, those employing a fluorescently labelled reagent) overcome many of the problems of direct sensors but require more sophisticated instrumentation because of the low light levels detected. In an attempt to combine the best features of the two techniques, an indirect SPR fluoroimmunoassay (SPRF) technique has been investigated. The surface field intensity enhancement produced by SPR is used to boost the emission from a fluorescently labelled immunoassay complex at a metal surface. The potential of the method is demonstrated by assaying for human Chorionic Gonadotrophin (hCG) in serum. Enhanced sensitivity over conventional total internal reflection fluorescence (TIRF) and SPR techniques was achieved.

Replication of simian foamy virus in monkey kidney cells.

The structure of foamy virus, its mode of maturation, and the origin of vacuoles in monkey kidney cells are described.