Repeated respiratory hospital encounters among children with asthma and residential proximity to traffic

OBJECTIVE

The prevalence of adverse respiratory outcomes among children has been frequently associated with measurements of traffic-related exposures, and other data suggest asthma severity is worsened with residence near heavy traffic. We examined the association between neighbourhood traffic burden and repeated acute respiratory illnesses that required emergency department visits and/or hospitalisation for children with a primary or secondary diagnosis of asthma (89% acute bronchitis or pneumonia).

METHODS

This is a hospital-based longitudinal study of a southern California urban catchment area around two adjacent children's hospitals. Subjects' home addresses were geocoded and linked to nearby traffic data. Recurrent event proportional hazard analysis was used to estimate the hazard of repeated hospital encounters.

RESULTS

We found living within 300 metres of arterial roads or freeways increased risk of repeated hospital encounters in 3297 children age 18 years or less. At highest risk were children in the top quintile of traffic density (HR = 1.21; 95% CL 0.99 to 1.49) and those who had 750 metres or more of arterial road and freeway length within 300 metres of their residence (HR = 1.18; 95% CL 0.99 to 1.41). Associations between repeated hospital encounters and residence near heavy traffic were stronger in females than males and in children without insurance or who required government sponsored insurance than children with private insurance. The gender disparity was most notable among infants (age 0) and children ages 6-18 years.

CONCLUSIONS

Results suggest exposure to traffic-related air pollution increases asthma severity as indicated by hospital utilisation. The finding in infants suggests this is an especially vulnerable population, although the validity of asthma diagnosis at this age is unknown. Females and children who do not have private insurance may also be more vulnerable to air pollution from traffic.

Psychotropic medications for patients with bipolar disorder in the United States: polytherapy and adherence

OBJECTIVE

Because treatments for bipolar disorder include a growing number of psychotropic agents, the authors evaluated psychotropic polytherapy and adherence to treatment among U.S. patients with bipolar disorder.

METHODS

National health plan claims data (2000-2004) were used to identify patients diagnosed as having bipolar disorder who had continuous benefits and had not been prescribed medication for bipolar disorder for six months or more. The study compared drugs dispensed to these patients initially and at one year and characterized patients who were adherent to mood-stabilizers.

RESULTS

A total of 7,406 patients had a bipolar disorder: bipolar I (55%), bipolar II (15%), or bipolar disorder not otherwise specified (30%). Women represented 57% of the sample; mean+/-SD age was 35.4+/-12.4 years. Initial prescription fills involved one psychotropic agent in 67% of patients, and two or more psychotropics (polytherapy) in 33%. Initial prescription drug selections involved: antidepressants > anticonvulsants >or= antipsychotics > sedatives > lithium; initial mood stabilizer use ranked: valproate > lithium > carbamazepine or oxcarbazepine > lamotrigine; antipsychotics ranked: olanzapine > quetiapine >or= risperidone > ziprasidone > aripiprazole > clozapine. Rankings were similar at one year, when only 31% of patients received monotherapy (a 2.2-fold decline), 32% received polytherapy, and 37% received no psychotropics. Initially patients received 1.42 psychotropic drugs per person; at one year, patients received 175, and at both times polytherapy was less likely with lithium than with anticonvulsants. In multivariate modeling, one-year mood stabilizer use was greater with the following: older age, type of mood stabilizer (lamotrigine > valproate > carbamazepine or oxcarbazepine > lithium) and was associated with more psychiatric office and emergency visits, clinician type (more common with psychiatrists than with primary care physicians), and nonuse of off-label anticonvulsants.

CONCLUSIONS

Polytherapy was used by one-third of patients initially and at one year, antidepressant use was highly prevalent initially and later, but lack of treatment was prevalent at one year. Plausible clinical and treatment factors were associated with sustained mood stabilizer adherence.

Exon 9 and exon 20 mutations in PIK3CA confer resistance to HER2 inhibitors in HER2-overexpressing breast cancer cells

Abstract #4054

The anti-tumor effect of HER2 antagonists in HER2-dependent breast cancer cells has been proposed to rely on inhibition of the phosphatidylinositol-3 kinase (PI3K)/Akt pathway. Mutations in the p110α catalytic subunit of PI3K occur in up to 40% of breast cancers and activation of this pathway has been implicated in resistance to the HER2 antibody trastuzumab (T). PIK3CA mutations cluster in two regions in the helical (E542K, E545K; exon 9) and catalytic (H1047R; exon 20) domains. We studied the role of these mutants in resistance to HER2 inhibitors in breast cancer cells with HER2 amplification. Two lines with endogenous H1047R p110 (PI3K), SUM190 and HCC1954, and SKBR3, SUM225, and BT474 cells stably transduced with retroviral vectors encoding HA-tagged wild-type, E545K, or H1047R p110, were studied for their response to the HER2 tyrosine kinase inhibitor lapatinib ditosylate (L; GW-572016) and T. In monolayer and 3D cell proliferation assays, partial resistance to L and T was conferred by either mutation compared to WT p110. After prolonged L treatment, Ser473 phosphorylation of Akt recovered in all cells with endogenous or ectopic p110 mutants in spite of continued inhibition of Y1248 P-HER2 and Y1289 P-HER3 by L. Further, BT474 cells with either p110 mutant could be passaged in the continued presence of L. Immunoprecipitation of p85, the regulatory subunit of PI3K, showed that PI3K association with HER3 was abrogated by T and L. RNAi of HER3 in MCF10A/HER2/PI3KE545K and MCF10A/HER2/PI3KH1047R cells markedly but not completely inhibited growth suggesting that the PI3K mutants may still depend on HER3 for full activation. We hypothesized that in cells with mutant PI3K, the mutants coexist in a pool with WT enzyme, and that mutant and WT p110α are bound to p85 in variable proportions. Experiments to measure whether the ratio of mutant to WT p110 bound to p85, assayed by mass spectrometry, will increase in the PI3K-mutant cells with acquired resistance to L are in progress. To test the role of these mutants on resistance to anti-HER2 therapies in vivo, athymic mice bearing BT474 xenografts with ectopic WT, E545K, or H1047R p110 are undergoing treatment with L and T. Finally, we analyzed mutations of PIK3CA in a cohort of 40 patients with locally advanced HER2+ breast cancer treated with weekly single-agent T for 3 weeks, followed by T with docetaxel for a total of 12 weeks before surgery (Mohsin et al. JCO 23:2460, 2005). Sequential core biopsies at weeks 1 and 3 after initiation of T were taken. Eight of 40 tumors (20%) expressed mutant PI3K, 2 in exon 9 and 6 in exon 20. PIK3CA mutations did not correlate with change in Ki67 (p=0.97) or cleaved caspase 3 (p=0.51) in weeks 1 or 3 of treatment nor with pathologic complete response (p=0.21). These data suggest that, if mutant PI3K confers relative resistance to T, a shorter time to recurrence may be a more robust endpoint as the initial cellular or clinical response may not be a good indicator of this resistance.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4054.

Gene expression analysis of Dupuytren's disease: the role of TGF-beta2

Dupuytren's disease is characterised by nodular fibroblastic proliferation of the palmar fascia leading to contracture of the hand. Transforming growth factor beta (TGF-beta) is thought to play a role in its pathogenesis. We performed a cDNA microarray analysis of Dupuytren's diseased cord tissue with an emphasis on TGF-beta isoforms. Normal-appearing transverse ligament of the palmar fascia from adjacent to the diseased cord and palmar fascia from patients undergoing carpal tunnel release were used as controls. TGF-beta gene expression was confirmed by quantitative real-time polymerase chain reaction. Over 20 unique genes were found to be significantly up-regulated, including several previously reported genes. A dominant increase in TGF-beta2 expression was seen in the cord tissue, whereas TGF-beta1 and TGF-beta3 were found not to be significantly up-regulated. Quantitative real-time polymerase chain reaction confirmed these findings. This gene expression profile allows for further experiments that may eventually lead to gene therapy to block the development and progression of Dupuytren's disease clinically.

Bipolar disorder and the metabolic syndrome: causal factors, psychiatric outcomes and economic burden

Overweight and obesity are highly prevalent in patients with bipolar disorder, and metabolic disorders also affect a significant portion of this population. Obesity and metabolic disorders cause significant economic burden and impair quality of life in both the general population and patients with bipolar disorder. This review examines the relationship between bipolar disorder and the metabolic syndrome, and the associated economic impact. The metabolic syndrome and bipolar disorder appear to share common risk factors, including endocrine disturbances, dysregulation of the sympathetic nervous system, and behaviour patterns, such as physical inactivity and overeating. In addition, many of the commonly used pharmacological treatments for bipolar disorder may intensify the medical burden in bipolar patients by causing weight gain and metabolic disturbances, including alterations in lipid and glucose metabolism, which can result in an increased risk for diabetes mellitus, hypertension, dyslipidaemia, cardiovascular disease and the metabolic syndrome. These medical co-morbidities and obesity have been associated with a worse disease course and likely contribute to the premature mortality observed in bipolar patients. Weight gain is also a major cause of treatment noncompliance, increased use of outpatient and inpatient services and, consequently, higher healthcare costs. Prevention of weight gain and metabolic disturbances or early intervention when these are present in bipolar disorder could result in significant health and economic benefits.

Psychotropic medications for patients with bipolar disorder in the United States: polytherapy and adherence

OBJECTIVE

Because treatments for bipolar disorder include a growing number of psychotropic agents, the authors evaluated psychotropic polytherapy and adherence to treatment among U.S. patients with bipolar disorder.

METHODS

National health plan claims data (2000-2004) were used to identify patients diagnosed as having bipolar disorder who had continuous benefits and had not been prescribed medication for bipolar disorder for six months or more. The study compared drugs dispensed to these patients initially and at one year and characterized patients who were adherent to mood-stabilizers.

RESULTS

A total of 7,406 patients had a bipolar disorder: bipolar I (55%), bipolar II (15%), or bipolar disorder not otherwise specified (30%). Women represented 57% of the sample; mean+/-SD age was 35.4+/-12.4 years. Initial prescription fills involved one psychotropic agent in 67% of patients, and two or more psychotropics (polytherapy) in 33%. Initial prescription drug selections involved: antidepressants > anticonvulsants >or= antipsychotics > sedatives > lithium; initial mood stabilizer use ranked: valproate > lithium > carbamazepine or oxcarbazepine > lamotrigine; antipsychotics ranked: olanzapine > quetiapine >or= risperidone > ziprasidone > aripiprazole > clozapine. Rankings were similar at one year, when only 31% of patients received monotherapy (a 2.2-fold decline), 32% received polytherapy, and 37% received no psychotropics. Initially patients received 1.42 psychotropic drugs per person; at one year, patients received 175, and at both times polytherapy was less likely with lithium than with anticonvulsants. In multivariate modeling, one-year mood stabilizer use was greater with the following: older age, type of mood stabilizer (lamotrigine > valproate > carbamazepine or oxcarbazepine > lithium) and was associated with more psychiatric office and emergency visits, clinician type (more common with psychiatrists than with primary care physicians), and nonuse of off-label anticonvulsants.

CONCLUSIONS

Polytherapy was used by one-third of patients initially and at one year, antidepressant use was highly prevalent initially and later, but lack of treatment was prevalent at one year. Plausible clinical and treatment factors were associated with sustained mood stabilizer adherence.

Surface tension of liquid ternary Fe-Cu-Mo alloys measured by electromagnetic levitation oscillating drop method

For the liquid Fe-Cu-Mo ternary system, the surface tensions of three selected alloys, i.e., three typical monotectic alloys, were measured by the electromagnetic levitation oscillating drop method over a broad temperature range, including both superheated and undercooled states. The maximum undercooling attained is up to 173 K. The experimental results show a good linear correlation between the surface tension and the temperature. By applying on the Butler equation, the surface tensions were also calculated and they are in good agreement with the measured ones, except that in the undercooled state, the calculated value is slightly larger than the measured results. Interestingly, both the measured and calculated results indicate that the enriched element on the droplet surface is much more conspicuous than other elements in influencing the surface tension. Besides, the viscosity and the density of the liquid Fe-Cu-Mo ternary alloys are also derived on the grounds of the experimentally measured surface tensions.

Coherent d-wave superconducting gap in underdoped La2-xSrxCuO4 by angle-resolved photoemission spectroscopy

We present angle-resolved photoemission spectroscopy data on moderately underdoped La1.855Sr0.145CuO4 at temperatures below and above the superconducting transition temperature. Unlike previous studies of this material, we observe sharp spectral peaks along the entire underlying Fermi surface in the superconducting state. These peaks trace out an energy gap that follows a simple d-wave form, with a maximum superconducting gap of 14 meV. Our results are consistent with a single gap picture for the cuprates. Furthermore our data on the even more underdoped sample La1.895Sr0.105CuO4 also show sharp spectral peaks, even at the antinode, with a maximum superconducting gap of 26 meV.