Effects of LRRK2 Inhibitors in Nonhuman Primates

Toxicology studies in nonhuman primates were conducted to evaluate selective, brain penetrant inhibitors of LRRK2. GNE 7915 was limited to 7-day administration in cynomolgus monkeys at 65 mg/kg/day or limited to 14 days in rhesus at 22.5 mg/kg b.i.d. due to physical signs. Compound 25 demonstrated acceptable tolerability at 50 and 225 mg/kg b.i.d. for 7 days in rhesus monkeys. MK-1468 was tolerated during 7-day administration at 100, 200 or 800 mg/kg/day or for 30-day administration at 30, 100, or 500 mg/kg b.i.d. in rhesus monkeys. The lungs revealed hypertrophy of type 2 pneumocytes, with accumulation of intra-alveolar macrophages. Transmission electron microscopy confirmed increased lamellar structures within hypertrophic type 2 pneumocytes. Hypertrophy and hyperplasia of type 2 pneumocytes with accumulation of intra-alveolar macrophages admixed with neutrophils were prominent at peripheral lungs of animals receiving compound 25 or MK-1468. Affected type 2 pneumocytes were immuno-positive for pro-surfactant C, but negative for CD11c, a marker for intra-alveolar macrophages. Accumulation of collagen within alveolar walls, confirmed by histochemical trichrome stain, accompanied changes described for compound 25 and MK-1468. Following a 12-week treatment-free interval, animals previously receiving MK-1468 for 30 days exhibited remodeling of alveolar structure and interstitial components that did not demonstrate reversibility.

Clinical utilisation of the Infant Monitor of vocal Production (IMP) for early identification of communication impairment in young infants at-risk of cerebral palsy: a prospective cohort study

AIM

To report prospective longitudinal data of early vocaliszations of infants identified "at-risk" of cerebral palsy (CP) for early identification of communication impairment.

METHOD

This case-control longitudinal prospective cohort study reports on the assessment of 36 infants, 18 identified as at-risk of CP at the time of enrolment and 18 typically developing (TD) children, at three time points: 6 months, 9 months and 12 months of age, Data were obtained through criterion and norm referenced assessments of vocaliszation behaviors.

RESULTS

Early vocal behaviors of infants identified as at-risk of CP did not differ from their age matched peers at 6 months of age, however, significant group differences emerged at 9 and 12 months when pre-canonical and canonical babble typically emerge. Generalized linear mixed models analysis showed that the rate of development of early language ability and more complex speech-related vocal behaviors was slower for infants at risk of CP when compared to TD infants, with over 75% of infants with CP showing below normal vocal production and impaired language by 12 months of age.

INTERPRETATION

Our data suggest characteristics of infant vocalizations associated with pre-canonical and canonical babbling provide a strong evidence base for predicting communication outcomes in infants at risk of CP.

Impact of periodontal intervention on local inflammation, periodontitis, and HIV outcomes

OBJECTIVE

The aim of this study was to determine active periodontal disease status in HIV and to determine the impact of periodontal disease resolution on HIV status.

METHODS

In this longitudinal cohort study, 73 HIV-positive subjects received comprehensive dental care. AAP, CDC/AAP, and BGI case definitions determined periodontal classification. Likelihood and frequency of moderate/severe periodontal disease were assessed based on demographic variables. The influence of periodontal intervention was assessed at baseline, 12, and 24 months. IL-6 was measured in a subset of subjects.

RESULTS

Of the periodontal classifications, BGI demonstrated the highest percentage category improvement with the intervention (>50%). Moderate/severe periodontitis was positively associated with HIV regardless of race, smoking status, gender, income level, and age, and was associated with increased IL-6. At baseline, the majority of subjects had severe periodontal disease regardless of ART status. Subjects with suppressed viral load at baseline demonstrated a significant improvement in BGI classification (P = 0.026), increased CD4 counts (P = 0.027), and decreased IL-6 levels (P = 0.03).

CONCLUSIONS

Periodontal inflammation was prevalent regardless of ART status. In virologically suppressed subjects, the intervention decreased periodontitis with a concomitant IL-6 decrease and CD4 increase. These findings suggest a relationship between periodontal inflammation, oral microbial translocation, and HIV status.

Gut microbiota correlates with energy gain from dietary fibre and appears to be associated with acute and chronic intestinal diseases

Improvements in high-throughput sequencing technologies have spurred a large number of studies aimed at obtaining a better understanding of the composition and the dynamics in gut microbiota and its associations with various human diseases, especially those in the intestinal tract. Here we briefly summarize results from three different such studies from our group, all of which used 454 based high-throughput 16S rRNA sequence analysis combined with other microbiota profiling methods to determine faecal microbiota composition. In the first study, a controlled feeding trial, we establish that energy gain from the consumption of up to 50 g/day of a resistant maltodextrin depends on the prevalent microbiota composition. Over time, resistant maltodextrin supplementation increased the proportion of total faecal bacteria as well as potentially beneficial bifidobacteria. Thus, energy gain from resistant maltodextrin in an individual appears to vary over time and depend on the adaptation of gut microbiota. We then illustrate the power of molecular tools for identifying (i) distortions in early microbiota development in pre-term infants and the presence of potentially novel pathogens contributing to necrotizing enterocolitis and (ii) a specific microbiota signature, based on discriminant analysis of the 16S rRNA sequences, that correlates with the prevalence of an early risk marker associated with colorectal carcinogenesis, intestinal adenoma, in elderly adults.

Seroprevalence of herpes simplex virus 2 among Hispanics in the USA: National Health and Nutrition Examination Survey, 2007-2008

To examine the seroprevalence of herpes simplex virus type 2 (HSV-2) among Hispanics in the USA, we used the cross-sectional, nationally representative National Health and Nutrition Examination Survey to compare the seroprevalence of HSV-2 between Hispanic persons of Mexican heritage and non-Mexican heritage aged 14-44 years, from survey years 2007-2008. The overall HSV-2 seroprevalence among Hispanics aged 14-44 years was 17.5% (95% confidence interval [CI], 15.2, 20.1) in the USA. HSV-2 seroprevalence was significantly lower among Mexican Americans than among other Hispanics (11.7% vs. 27.8%, P < 0.01). Prevalence of HSV-2 was also significantly associated with gender and age. The significant difference in HSV-2 seroprevalence between Hispanic persons of Mexican heritage and non-Mexican heritage suggested that targeting specific subgroups of Hispanics for preventive interventions may be a strategy to reduce the transmission of HSV-2 and HIV among Hispanics in the USA.

Double-blind crossover study to assess potential differences in cytochrome P450 3A4 activity in healthy subjects receiving ondansetron plus dexamethasone, with and without aprepitant

PURPOSE

Because glucocorticoids and the neurokinin-1 receptor antagonist aprepitant influence CYP3A4 activity, this study assessed whether aprepitant added to a 5-HT(3) antagonist and glucocorticoid would affect CYP3A4 induction.

METHODS

In this double-blind, 2-period crossover study, 12 subjects were randomized to receive a triple regimen (oral aprepitant [A] 125 mg, intravenous ondansetron [O] 32 mg, and oral dexamethasone [D] 12 mg day 1; A 80 mg and D 8 mg days 2-3; D 8 mg day 4) in 1 of 2 periods, and a dual regimen (O 32 mg and D 20 mg day 1; D 8 mg bid days 2-4); the D dose was adjusted to account for known dexamethasone/aprepitant interaction. Oral (2 mg) and intravenous (1 mg) stable isotope ((13)C(5) (15)N(1))-labeled midazolam were simultaneously given as probes on days -1, 6, 8, 15, and 22 of each period. If the a priori 90% confidence interval for the day 6 geometric mean oral midazolam AUC(0-∞) ratio (triple/dual regimen) of fold-change from baseline was above 0.5, it would be concluded that there was no clinically meaningful between-regimen difference in CYP3A4 activity.

RESULTS

Day 6 oral midazolam AUC(0-∞) geometric mean fold-change from baseline was 0.84 (0.30-1.58 with A, 0.46-1.69 without A). The ratio of geometric mean oral midazolam AUC(0-∞) fold-changes was 1.00 (90% confidence interval 0.80, 1.25).

CONCLUSIONS

Aprepitant plus a 5-HT(3) antagonist and dexamethasone is unlikely to have a significant additional inductive effect on CYP3A4 activity beyond that of the dual regimen.

Aprepitant in adolescent patients for prevention of chemotherapy-induced nausea and vomiting: a randomized, double-blind, placebo-controlled study of efficacy and tolerability

BACKGROUND

The neurokinin-1 receptor antagonist aprepitant, plus a 5HT3 antagonist and corticosteroid is well-tolerated and effective in preventing chemotherapy-induced nausea and vomiting in adults but has not been formally assessed in adolescents.

PROCEDURE

Patients age 11-19 years old receiving emetogenic chemotherapy were randomized 2:1 to aprepitant triple therapy (aprepitant [A] 125 mg p.o., dexamethasone [D] 8 mg p.o., and ondansetron [O] 0.15 mg/kg i.v. t.i.d. day 1; A 80 mg, D 4 mg, and O 0.15 mg/kg t.i.d. day 2; A 80 mg and D 4 mg day 3; and D 4 mg day 4) or a control regimen (D 16 mg and O 0.15 mg/kg t.i.d. day 1; D 8 mg and O 0.15 mg/kg t.i.d. day 2; and D 8 mg days 3 and 4). The primary endpoint was the difference in drug-related adverse events during and for 14 days following treatment. Efficacy and aprepitant pharmacokinetics were assessed.

RESULTS

Baseline characteristics were similar between aprepitant (N = 28) and control (N = 18) groups. Febrile neutropenia was more frequent in the aprepitant group (25% vs. 11.1%). Complete response (CR) rates were 35.7% for aprepitant triple therapy versus 5.6% for the control group. Mean plasma aprepitant AUC(0-24 hr) and C(max) on day 1 and mean trough concentrations on days 2 and 3 were consistently lower compared to historical data obtained from healthy adults; however, the differences were not clinically significant.

CONCLUSION

Aprepitant triple therapy was generally well tolerated; CR were greater with aprepitant, although not statistically significant. Pharmacokinetics suggest that the adult dosing regimen is appropriate for adolescents.

Upper limb corticomotor projections and physiological changes that occur with botulinum toxin-A therapy in children with hemiplegic cerebral palsy

AIM

To investigate the corticomotor projection to the upper limb in children with hemiplegic cerebral palsy (CP) and the changes that occur with botulinum toxin (BTX)-A.

METHODS

The study design is a pilot prospective randomized trial. Twenty-two children with hemiplegic CP aged 7 years to 13 years 11 months were recruited. Treatment group (12) received one series of BTX-A injections into the upper limb. Control group (10) did not receive upper limb BTX-A. All participants except one treatment group participant also received lower limb BTX-A. Transcranial magnetic stimulation (TMS) was performed at baseline, and 1, 3 and 6 months post-injection. Outcome measures were: change in position of affected and unaffected side first dorsal interosseous optimal site of stimulation (OPTx).

RESULTS

A shift in affected and unaffected side OPTx was observed for both treatment and control groups, and there was no statistically significant difference between groups at 1, 3 or 6 months. Poor tolerance of TMS cortical stimuli >80% was observed.

CONCLUSION

Corticomotor projections associated with the upper limb in children with hemiplegic CP show significant variability over a 6-month period. This variability may reflect central motor reorganization because of systemic BTX-A effect or developmental changes. Upper limb BTX-A therapy is associated with reorganization of both affected and unaffected projections. Poor tolerance of the TMS procedure, in conjunction with higher cortical thresholds, may limit the usefulness of TMS as an investigatory tool in young children with movement disorders.

Metabolism and disposition of 1-bromopropane in rats and mice following inhalation or intravenous administration

Workplace exposure to 1-bromopropane (1-BrP) can potentially occur during its use in spray adhesives, fats, waxes, and resins. 1-BrP may be used to replace ozone depleting solvents, resulting in an increase in its annual production in the US, which currently exceeds 1 million pounds. The potential for human exposure to 1-BrP and the reports of adverse effects associated with potential occupational exposure to high levels of 1-BrP have increased the need for the development of biomarkers of exposure and an improved understanding of 1-BrP metabolism and disposition. In this study, the factors influencing the disposition and biotransformation of 1-BrP were examined in male F344 rats and B6C3F1 mice following inhalation exposure (800 ppm) or intravenous administration (5, 20, and 100 mg/kg). [1,2,3-(13)C]1-BrP and [1-(14)C]1-BrP were administered to enable characterization of urinary metabolites using NMR spectroscopy, LC-MS/MS, and HPLC coupled radiochromatography. Exhaled breath volatile organic chemicals (VOC), exhaled CO(2), urine, feces, and tissues were collected for up to 48 h post-administration for determination of radioactivity distribution. Rats and mice exhaled a majority of the administered dose as either VOC (40-72%) or (14)CO(2) (10-30%). For rats, but not mice, the percentage of the dose exhaled as VOC increased between the mid ( approximately 50%) and high ( approximately 71%) dose groups; while the percentage of the dose exhaled as (14)CO(2) decreased (19 to 10%). The molar ratio of exhaled (14)CO(2) to total released bromide, which decreased as dose increased, demonstrated that the proportion of 1-BrP metabolized via oxidation relative to pathways dependent on glutathione conjugation is inversely proportional to dose in the rat. [(14)C]1-BrP equivalents were recovered in urine (13-17%, rats; 14-23% mice), feces (<2%), or retained in the tissues and carcass (<6%) of rats and mice administered i.v. 5 to 100 mg/kg [(14)C]1-BrP. Metabolites characterized in urine of rats and mice include N-acetyl-S-propylcysteine, N-acetyl-3-(propylsulfinyl)alanine, N-acetyl-S-(2-hydroxypropyl)cysteine, 1-bromo-2-hydroxypropane-O-glucuronide, N-acetyl-S-(2-oxopropyl)cysteine, and N-acetyl-3-[(2-oxopropyl)sulfinyl]alanine. These metabolites may be formed following oxidation of 1-bromopropane to 1-bromo-2-propanol and bromoacetone and following subsequent glutathione conjugation with either of these compounds. Rats pretreated with 1-aminobenzotriazole (ABT), a potent inhibitor of P450 excreted less in urine (down 30%), exhaled as (14)CO2 (down 80%), or retained in liver (down 90%), with a concomitant increase in radioactivity expired as VOC (up 52%). Following ABT pretreatment, rat urinary metabolites were reduced in number from 10 to 1, N-acetyl-S-propylcysteine, which accounted for >90% of the total urinary radioactivity in ABT pretreated rats. Together, these data demonstrate a role for cytochrome P450 and glutathione in the dose-dependent metabolism and disposition of 1-BrP in the rat.

The quantification of paracetamol, paracetamol glucuronide and paracetamol sulphate in plasma and urine using a single high-performance liquid chromatography assay

A range of analytical methods exist for the determination of paracetamol in biological fluids. However, to understand the fate of paracetamol and the effect of other drugs on its disposition in vivo, the major metabolites require quantification in urine and plasma. A method to simultaneously quantify paracetamol, paracetamol glucuronide (PG) and paracetamol sulphate (PS) in plasma and urine with superior sensitivity is therefore desired, especially if the volume of plasma available is low. A simple isocratic reverse phase high-performance liquid chromatography (HPLC) assay with spectrophotometric detection has been developed. The method, requiring only 100 microl of plasma and 50 microl of urine, utilizes a reversed-phase C18 column, a wavelength of 254 nm for detection and a mobile phase composed of potassium dihydrogen orthophosphate (0.1 M)-isopropanol-tetrahydrofuran (THF) (100:1.5:0.1, v/v/v) adjusted to pH 3.7 with phosphoric acid. The method is sensitive and linear in plasma within a concentration range from 0.4 to 200 microM for paracetamol, PG and PS. For PG and PS in urine, the method is sensitive and linear within a concentration range from 100 to 20,000 microM. Over these ranges, accuracy and precision were less than 12%. The assay has been used to measure concentrations of paracetamol and the two metabolites in plasma collected by finger-prick sampling and of the metabolites in urine from healthy volunteers administered a single oral dose of 1000 mg of paracetamol.

Mutation in Brca2 stimulates error-prone homology-directed repair of DNA double-strand breaks occurring between repeated sequences

Mutation of BRCA2 causes familial early onset breast and ovarian cancer. BRCA2 has been suggested to be important for the maintenance of genome integrity and to have a role in DNA repair by homology- directed double-strand break (DSB) repair. By studying the repair of a specific induced chromosomal DSB we show that loss of Brca2 leads to a substantial increase in error-prone repair by homology-directed single-strand annealing and a reduction in DSB repair by conservative gene conversion. These data demonstrate that loss of Brca2 causes misrepair of chromosomal DSBs occurring between repeated sequences by stimulating use of an error-prone homologous recombination pathway. Furthermore, loss of Brca2 causes a large increase in genome-wide error-prone repair of both spontaneous DNA damage and mitomycin C-induced DNA cross-links at the expense of error-free repair by sister chromatid recombination. This provides insight into the mechanisms that induce genome instability in tumour cells lacking BRCA2.

The ascertainment and management of tuberculosis in Tayside, Scotland during 1993-94

OBJECTIVE

To evaluate whether utilising a database of dispensed prescriptions for anti-tuberculous chemotherapy could improve case ascertainment compared to standard methods. A further objective was to assess whether cases were managed according to standard guidelines.

DESIGN

Retrospective case note audit.

SETTING

Tayside, Scotland

SUBJECTS

Patients identified by conventional (i.e. SMRI diagnostic codes, notifications to the Health Board, microbiology and pathology reports) and the data base (MEMO) as potentially having tuberculosis and receiving treatment between 1st January 1993 and 31st December 1994. One hundred and ninety one potential cases were identified. One hundred and twenty two case notes were obtained for review. Eighty eight of these were initially thought to have tuberculosis and the results below refer to these 88 cases.

RESULTS

MEMO identified 43 cases not found by conventional methods. Cases identified by MEMO were more likely to have been managed as outpatients and less likely to have positive microbiology than cases identified by conventional means. Only 26 cases were notified to the Health Board, including all smear positive cases.

CONCLUSIONS

Notification of tuberculosis continues to be incomplete. Use of the MEMO system almost doubled case ascertainment. The absence of a firm diagnosis may lead to a reluctance to notify cases being treated as tuberculosis.

Gestational exposure to cocaine or pharmacologically related compounds: effects on behavior and striatal dopamine receptors

Gestational cocaine (COC) exposure has been reported to alter behavior and possibly dopamine (DA) receptors. In this paper, we further examined the effects of prenatal COC (40 mg/kg, s.c.) on DA receptor binding and the behavioral response to quinpirole, a DA D2 receptor agonist. In an attempt to elucidate possible mechanisms of such effects, we exposed pregnant dams to specific reuptake blockers; fluoxetine 12.5 mg/kg, a serotonin reuptake blocker; desipramine 10 mg/kg, a norepinephrine reuptake blocker; GBR-12909 10 mg/kg, a DA reuptake blocker; or to a local anesthetic, lidocaine 40 mg/kg. Drugs were administered once daily over gestational days 8-20. Control dams were injected with saline (SAL) or pair-fed to the COC group. Quinpirole challenge was performed in the offspring on post natal day 19. Two pups per litter were injected (s.c.) with 0.03 or 0.09 mg/kg quinpirole-HCl on post-natal day 19. The remaining pups in each litter were sacrificed for analysis of striatal DA receptors. Results showed that only COC exposure altered the behavioral response to the quinpirole challenge by increasing quinpirole-induced stereotypy and motor activity relative to SAL controls. DA receptor analysis showed no alteration in K(D) or B(MAX) for striatal D1 or D2 sites in any group. These results suggest that prenatal COC exposure produces alterations in function of the D2 receptor complex which are not reflected in K(D) or B(MAX) and that these effects are not fully mimicked by exposure to specific monoamine reuptake blockers or a local anesthetic.

Syphilis outbreak assessment

BACKGROUND

Syphilis rates began to decline in 1991 and have decreased every year since. In 1998, 6,993 cases of primary and secondary syphilis were reported in the United States, for a national incidence of 2.6 cases per 100,000 population. Although syphilis rates are at an historic low, focal outbreaks still occur. On October 7, 1999, the Division of Sexually Transmitted Disease Prevention of the Centers for Disease Control and Prevention, in collaboration with federal and community partners, presented the National Plan for Elimination of Syphilis from the United States. One of the five key strategies of the plan is rapid outbreak response.

METHODS

Methods for outbreak assessment and response were reviewed in the literature, synthesized, and adapted for use in syphilis outbreaks.

RESULTS

Key elements of outbreak assessment and response are detection, surveillance data review, hypothesis generation, intervention development, and the evaluation of clinical, public health, and laboratory services.

CONCLUSIONS

Outbreak response necessitates community participation and a coordinated interdisciplinary effort to determine social and behavioral contributors to the outbreak and to develop targeted interventions.

Incidental splenic injury during abdominal vascular surgery: a case-controlled analysis

BACKGROUND

The small but finite risk of postsplenectomy sepsis is generally regarded as a firm indication for splenic preservation after iatrogenic injury, especially in the young. But splenectomy may be preferable in patients who sustain splenic injuries during vascular operations because of the potential for continued bleeding associated with anticoagulation. The purpose of this study was to determine the perioperative morbidity of incidental splenectomy among patients undergoing abdominal vascular operations.

STUDY DESIGN

We studied 17 patients who underwent incidental splenectomy at the time of abdominal vascular operations. Complete data collected on each subject included preoperative and postoperative blood counts, operative indications and details, transfusion requirements, length of hospital stay, and outcomes. Using age- and gender-matched case controls undergoing identical vascular operations from the same period, we evaluated the complication rate and outcomes of patients who underwent splenectomy for iatrogenic injuries of the spleen, versus those who did not sustain splenic injuries.

RESULTS

The estimated prevalence of iatrogenic splenic injury during the study period was 0.5%. Mean operative time, estimated blood loss, and duration of mechanical ventilation tended to be greater in the splenectomy patients, but the differences did not achieve statistical significance. Splenorrhaphy was attempted in seven patients, but continued bleeding mandated spleen removal in all cases. Splenectomy patients had a higher transfusion requirement (p = 0.03) and a longer mean length of stay (p = 0.03) than controls. Compared with controls, there was a higher prevalence of infectious complications in the splenectomy patients (p = 0.015), but there was no difference in the prevalence of thromboembolic complications between groups. Two of the splenectomy patients died in the postoperative period from multisystem organ failure, and one died of a missed splenic injury.

CONCLUSIONS

These data suggest that incidental splenectomy during abdominal vascular operations is associated with increased postoperative infectious complications and prolonged hospitalization.

Managerialism and active citizenship in Britain's reformed health service: power and community in an era of decentralisation

The creation of a large managerial stratum within the British National Health Service in recent years has been one of the most striking characteristics of reforms intended to develop a more efficient and "business-like" service. An accompanying political rhetoric of decentralisation has cast local managerial autonomy as a means to gauge and respond more easily to the needs and preferences expressed by local communities. This article therefore reviews the growth of the new managerial stratum with particular regard to its emerging relationship with the local populations in whose name the organisational reforms have been wrought. The dominant political interpretation of this relationship--that the organisational reforms constitute a movement from leaden "bureaucratic" administration to more locally accountable and responsive managerial regimes--is then tested with regard to an in-depth study of two health authorities responsible for very different local populations. Results show that the role of local populations in influencing decisions and determining priorities is considerably less than inferred by the sustained political rhetoric in favour of the "local voices". Consideration of possible trends in the state and economy suggests however that this disjuncture may not be explicable solely in terms of the new managerial stratum maximising its influence or of central government retaining a high degree of control.

Predictive model of weapon carrying among urban high school students: results and validation

OBJECTIVES

The purpose of this study was to identify the behavioral, psychosocial, and demographic predictors of self-reported weapon carrying among secondary school students who attend urban public schools.

METHODS

Self-reported weapon carrying was measured in a schoolwide anonymous health survey conducted in two demographically comparable high schools in 1992, in Boston, Massachusetts. Indicators of self-perception, depression, stressful life events, and adolescent risk behaviors of substance use and sexual behavior, along with self-reported weapon carrying, were measured. The students in both schools were racially heterogeneous, with the majority of about 80% from black or Hispanic backgrounds. A predictive model was developed using a forward stepwise logistic regression model in one inner-city high school, and tested in a second high school.

RESULTS

Self-reported lifetime weapon carrying was 32% overall. The major predictors of weapon carrying among urban secondary school students are a combination of demographic, psychosocial, behavioral, and school-related factors. This analysis indicates consistency in eight markers predictive of weapon carrying: lower age, male gender, regular marijuana use, sexual experience, having witnessed a crime, having skipped school, suicidal ideation, and having hit or "beat up" someone. Race parental education, and family composition were not significant predictors. Significant predictors of weapon carrying were marijuana use and sexual experience, each of which was consistently high in both schools.

CONCLUSIONS

The model-building and validation presented in this study provide empirical evidence for three important conclusions. First, weapon carrying is associated with multiple and interrelated factors which include demographic, psychosocial, behavioral, and school-related characteristics of high school-age adolescents. Second, students with more risk factors are more likely to carry a weapon, suggesting that the variables are independent markers. Third, this study identified marijuana use and being sexually experienced as both highly predictive of weapon carrying. Implications of this study for prevention point to the need for comprehensive multidisciplinary services in high school that include mental health counseling as well as health education efforts aimed at behavior change.

Imaging soft X-rays with opaque spheres

Images of small fluorescence X-ray sources obtained by diffraction with opaque spheres were recorded with a flow-proportional counter and on X-ray sensitive film. Image fluxes and intensities obtained experimentally were compared with theoretical estimates made using analytical expressions derived from the sphere's point-source imaging properties.

Expressed sequences from conidial, mycelial, and sexual stages of Neurospora crassa

In the Neurospora Genome Project at the University of New Mexico, expressed sequence tags (ESTs) corresponding to three stages of the life cycle of the filamentous fungus Neurospora crassa are being analyzed. The results of a pilot project to identify expressed genes and determine their patterns of expression are presented. 1,865 partial complementary DNA (cDNA) sequences for 1,409 clones were determined using single-pass sequencing. Contig analysis allowed the identification of 838 unique ESTs and 156 ESTs present in multiple cDNA clones. For about 34% of the sequences, highly or moderately significant matches to sequences (of known and unknown function) in the NCBI database were detected. Approximately 56% of the ESTs showed no similarity to previously identified genes. Among genes with assigned function, about 43.3% were involved in metabolism, 32.9% in protein synthesis and 8.4% in RNA synthesis. Fewer were involved in defense (6%), cell signalling (3.4%), cell structure (3.4%) and cell division (2.6%).

Increase of manganese superoxide dismutase, but not of Cu/Zn-SOD, in experimental optic neuritis

PURPOSE

To evaluate the role of manganese superoxide dismutase (Mn-SOD) and copper/zinc superoxide dismutase (Cu/Zn-SOD) in cellular protection of the optic nerve against the oxidative injury that contributes to demyelination in experimental allergic encephalomyelitis (EAE).

METHODS

Immunocytochemistry for Mn-SOD and Cu/Zn-SOD and ultracytochemical localization of hydrogen peroxide (H2O2) were performed on the optic nerves of guinea pigs with EAE and normal guinea pigs. Cell-specific enzyme expression of SOD was quantitated by computerized morphometric analysis.

RESULTS

Light microscopy showed a perivascular distribution of Mn-SOD-positive cells in the optic nerves of animals with EAE. Electron microscopy showed that the Mn-SOD immunogold was confined exclusively to mitochondria, whereas Cu/Zn-SOD immunogold was found in the cytoplasmic matrix and nucleus of cells of the optic nerve in both animals with EAE and normal animals. Results of quantitative analysis of the optic nerves of animals with EAE showed an 8-fold increase in Mn-SOD immunogold in astroglial cells and a 13-fold increase in microglial/phagocytic cells in comparison with that of normal animals. Increases in Mn-SOD immunogold were contiguous to H2O2-derived reaction product. No increases in Cu/Zn-SOD immunogold were detected in EAE.

CONCLUSIONS

Increases in Mn-SOD activity in astroglial cells and microglial/phagocytic cells may contribute to the relative sparing of these cells from injury in EAE, whereas the low level of Mn-SOD in oligodendroglial cells and axons may increase their vulnerability to the effects of superoxide-induced oxidative injury that results in demyelination.

Thyroid function in a population of children with attention deficit hyperactivity disorder

OBJECTIVE

To determine the prevalence of thyroid hormone abnormalities and generalized resistance to thyroid hormone in a population of children with attention deficit hyperactivity disorder (ADHD) as compared to reference ranges determined from a control population and hence to determine if routine thyroid hormone screening in children with non-familial ADHD is indicated.

METHOD

Children attending the State Child Development Centre in Perth, Western Australia with ADHD, as defined by the Diagnostic and Statistical Manual of Mental Disorders (fourth edition) provided the study population. The control population consisted of 353 normal children with a history of allergy in whom radioallergosorbent (RAST) testing was being performed.

RESULTS

The prevalence of thyroid hormone abnormalities in the study population was 2.3% (95% CI 0.6%, 5.7%). There were no cases of generalized resistance to thyroid hormone. The prevalence of thyroid hormone abnormalities in the general population of children and adolescents has been reported to vary between 1 and 3.7%.

CONCLUSION

Routine thyroid hormone screening is not indicated in children with non-familial ADHD.

National trends in the use of stimulant medication for attention deficit hyperactivity disorder

OBJECTIVE

To document the use of stimulant medication in the different states and territories of Australia in 1993 and trends in use of stimulant medication in Western Australia and New South Wales from 1988 to 1993.

METHODOLOGY

Health authorities in the states and territories of Australia were contacted and requested to provided data on total numbers, patient gender, date of birth, postcode and type of stimulant medication prescribed to estimate the prevalence of use of stimulant medication in Australia.

RESULTS

Despite variation in the data obtained from each health authority there is a significant difference in the rates of use of stimulant medication between states and territories in Australia, and a significant increase in use between 1988 and 1993 in Western Australia and New South Wales.

CONCLUSIONS

These trends should continue to be closely monitored and the possibility of establishing national prescription guidelines considered.

Defining the components of street outreach for HIV prevention: the contact and the encounter

Health departments and community-based organizations across the United States are funded by the Centers for Disease Control and Prevention to conduct street outreach to facilitate risk reduction among a variety of hard-to-reach populations who are at risk for human immunodeficiency virus infection and other sexually transmitted diseases. The interaction between the client and outreach worker is the fundamental element of any street outreach activity. However, little has been written about the relationships that develop on the street between workers and clients to promote, support, and sustain behavior change. This paper describes two types of interactions that occur in street outreach intervention activities: the contact and the encounter. As part of a comprehensive evaluation of street outreach, interactions between workers and clients were described and analyzed during the formative phase of the AIDS Evaluation of Street Outreach Projects. For purposes of the evaluation, a contact was defined as a face-to-face interaction during which materials and/or information are exchanged between an outreach worker and a client (or small group of clients). An encounter was defined as a face-to-face interaction between a worker and client going beyond the contact to include individual assessment, specific service delivery in response to the client's identified need(s), and a planned follow-up. The contact provides a means to initiate interaction with potential clients in the community. It is the encounter that provides more significant opportunity for helping the client initiate and sustain behavior change. The discussion suggests techniques for enhancing the encounter between outreach workers and clients using the conceptual framework of the social work helping relationship. Five elements of the encounter are defined and developed: screening, engagement, assessment, service delivery, and follow-up. The encounter represents an enhancement of the traditional street outreach interaction and a more systematic approach to promoting the behavioral change goals of the AIDS Evaluation of Street Outreach Projects. Recommendations are suggested for implementing the encounter in street outreach programs serving hard-to-reach populations.

Phase I trial of intravenous carboplatin added to oral etoposide and oral cyclophosphamide for stage IV non-small cell lung cancer

The combination of oral etoposide and oral cyclophosphamide is an active and easily administered outpatient regimen for non-small cell lung cancer with leukopenia as the most common severe toxicity. To maintain ease of outpatient administration and to take advantage of a differing dose-limiting toxicity, we attempted to add escalating doses of intravenous carboplatin to full-dose oral etoposide and oral cyclophosphamide for chemotherapy-naive patients with Stage IV non-small cell lung cancer. The first 4 patients received etoposide and cyclophosphamide (each at 50 mg PO BID Days 1-12 every 28 days) with intravenous carboplatin on Day 1 at a dose calculated by the Calvert formula to achieve AUC 4. With this regimen dose-limiting toxicity (2 patients with Grade 4 leukopenia/granulocytopenia) was noted. An additional 3 patients therefore received etoposide and cyclophosphamide at a 25% reduced dose (each at 50 mg PO BID Days 1-9 every 28 days) with intravenous carboplatin on Day 1 at a dose calculated to achieve AUC 4. Dose-limiting toxicity (2 patients with Grade 4 leukopenia/granulocytopenia) was again noted. One patient achieved a partial response maintained for 6 months. However potentiation of leukopenia/granulocytopenia by carboplatin prevents full-dose use of either cyclophosphamide and etoposide or of carboplatin in this regimen.

Reflux during positive pressure ventilation through the laryngeal mask

Patients undergoing anaesthesia for cataract surgery were anaesthetized and their lungs ventilated by intermittent positive pressure ventilation. In one group, ventilation was facilitated by tracheal intubation and in the other group by laryngeal mask airway (LMA). Reflux of stomach contents into the oesophagus was monitored continuously using an indwelling oesophageal pH electrode. The number of discrete episodes of reflux was higher in the LMA group (P = 0.0178), as was the incidence of reflux at antagonism of neuromuscular block (P = 0.0349).

Whole-blood serotonin and cognitive functioning in autistic individuals and their first-degree relatives

The relationship between cognitive-intellectual abilities and whole-blood serotonin (5-hydroxytryptamine; 5-HT) in 18 autistic probands and their first-degree relatives (n = 21 parents, n = 13 siblings) was investigated. Whole-blood 5-HT was significantly negatively associated with verbal-expressive/symbolic abilities for the entire sample. The proportion of variance in cognitive-intellectual performances attributable to whole-blood 5-HT was substantial in the context of variance attributable to familial classification. The relationship between verbal-expressive abilities and whole-blood 5-HT, adjusted for race and familial classification, was noteworthy. Simple correlations between 5-HT and cognitive-intellectual performances were conducted. However, bias related to covariance attributable to race seriously limits such findings. The issue of bias and its relevance to previous research is discussed further.

Acute respiratory failure and ECMO

In recent years, we have experienced advances in treatments for severe ARDS. One that holds promise for these critically ill adult patients is ECMO, which can provide gas exchange and lung rest for the patient in severe reversible respiratory failure. Advances in ECMO techniques, appropriate patient selection and the development of heparinized tubing will all improve the potential for survival in patients who are placed on ECMO therapy in the future.

Acute respiratory failure and ECMO

In recent years, we have experienced advances in treatments for severe ARDS. One that holds promise for these critically ill adult patients is ECMO, which can provide gas exchange and lung rest for the patient in severe reversible respiratory failure. Advances in ECMO techniques, appropriate patient selection and the development of heparinized tubing will all improve the potential for survival in patients who are placed on ECMO therapy in the future.

Implementation of a computerized information system in a long-term care facility

The successful implementation of computerized nursing information systems requires the completion of many tasks and the participation of many persons. In 1989, Pulliam and Boettcher described a six-step process for introducing computerized information systems into long-term care facilities. This article describes the process, particularly the implementation phase, as it actually happened in a 124-bed facility in a mid-Atlantic state. This facility found that successful implementation requires a systems coordinator who is a professional nurse who understands the needs of the patients, can integrate information with the computer system, and can provide on-going support for the users.

Traumatic hemipelvectomy

Traumatic hemipelvectomy is an uncommon and devastating injury with few patients alive when they reach the hospital. There are only 19 reported survivors of this injury. This group includes 17 males and 2 females. All had severe, associated injuries. The mechanism of injury involved motorcycle, automobile, pedestrian/motor vehicle, or heavy machinery accidents. All surviving patients are young (10-34 years of age). Most suffered from a variety of postoperative complications. Two interesting patients with traumatic hemipelvectomy are reported. One involves a new mechanism of injury, the propellor of a motorboat. The management of these 2 patients is explained, the experience of others with similar injuries is reviewed, and the benefit of reconstruction with the gluteus myocutaneous flap is discussed.

Construction and expression of alpha 1-proteinase inhibitor mutants and the effects of these mutations on secretion of the variant inhibitors

Human alpha 1-proteinase inhibitor (A1Pi) deficiency, associated with the Z variant A1Pi gene, results from defective secretion of the inhibitor from the liver and appears to be a direct consequence of replacement of Glu342 with Lys. To investigate the effect of the amino acid occupying position 342 on secretion of A1Pi, we have used oligonucleotide-directed mutagenesis of A1Pi cDNA to randomly change the codon specifying this amino acid. Since replacement of Glu342 by Lys leads to a change in the predicted secondary structure for this protein, we also tested the possibility that defective secretion of A1PiZ is the result of this type of alteration. For this purpose, site-directed mutagenesis was used to produce sequences encoding A1Pi retaining Glu342 but predicted to have A1PiZ type secondary structure. The effects of 10 different amino acids occupying position 342 on the secretion of A1Pi were determined by pulse-chase experiments and by enzyme-linked immunosorbent assay of medium from transiently transfected COS cells. Results of these studies show that secretion of A1Pi is most efficient when position 342 is occupied by a negatively charged amino acid, efficient but somewhat less so when occupied by a neutral amino acid, and least efficient when a positively charged residue is present. The mutation designed to alter secondary structure had no effect on the secretion of A1Pi. As indicated by immunofluorescence microscopy and mobility of intracellular A1Pi on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lowered secretion is accompanied by accumulation of A1Pi in the endoplasmic reticulum of the transfected cells. These results are compatible with the ideas that secretion of A1Pi is directly influenced by the amino acid occupying position 342, that a positively charged amino acid in this position is especially detrimental to secretion of this protein, and that the rate-limiting step in the secretion of the altered forms is transport from endoplasmic reticulum to Golgi.

Electromagnetic field focusing (EFF) probe for intravascular endarterectomy. Preliminary feasibility study

Vaporization of atheromas in 10 human aorta segments immersed under flowing blood in vitro were done using the EFF probe. No increase in packed cells of the flowing blood following atheroma vaporization were noted suggesting absence of post vaporization debris. No damage to the aorta underlying the vaporized atheroma was noted on light microscopy suggesting well localized vaporization process. This study suggests that EFF probe might be a safe tool for intravascular endarterectomy.