A Quasi-Experimental Analysis of Elementary School Absences and Fine Particulate Air Pollution

Fine particulate air pollution (PM_2.5) has been associated with many adverse health outcomes including school absences. Specifically, a previous study in the Utah Valley area, conducted during a time with relatively high air pollution exposure, found significant positive correlations between school absences and air pollution.We examined the hypothesis that ambient PM_2.5 exposures are associated with elementary school absences using a quasi-natural experiment to help control for observed and unobserved structural factors that influence school absences. The Alpine, Provo, and Salt Lake City school districts are located in valleys subject to daily mean PM_2.5 concentrations almost twice as high as those in the Park City School District. We used seminonparametric generalized additive Poisson regression models to evaluate associations between absences and daily PM_2.5 levels in the 3 districts that were exposed to the most pollution while using Park City absences as a quasi-control. The study covered 3 school years (2011/12-2013/14).School absences were most strongly associated with observed structural factors such as seasonal trends across school years, day-of-week effects, holiday effects, weather, etc. However, after controlling for these structural factors directly and using a control district, a 10 μg/m³ increase in PM_2.5 was associated with an approximately 1.7% increase in daily elementary school absences.Exposure to ambient air pollution can contribute to elementary school absences, although this effect is difficult to disentangle from various other factors.     

The growing commercial value of the male body: a longitudinal survey of advertising in women's magazines.

BACKGROUND: With the advances of feminism, men have gradually relinquished their once-exclusive 'masculine' roles as fighters and breadwinners. In response to this change, the male body may have gained in relative importance as one of the few surviving marks of masculinity. We hypothesized that these trends might be quantified by using a commercial measure such as advertising. METHODS: We examined the proportion of exposed male and female bodies portrayed in advertisements between 1958 and 1998 in two leading American women's magazines. RESULTS: In both magazines, the proportion of undressed women in the advertisements has changed little over the last 40 years, whereas the proportion of undressed men has increased dramatically, especially since the early 1980s. CONCLUSIONS: Trends in commercial advertising offer tentative support for the hypothesis that the male body is increasing in importance as a mark of masculinity--at least as judged from the actions of advertisers seeking to influence women's attitudes.     

Ixabepilone in combination with capecitabine and as monotherapy for treatment of advanced breast cancer refractory to previous chemotherapies

PURPOSE: To describe the considerations leading to marketing approval of ixabepilone in combination with capecitabine and as monotherapy for the treatment of advanced breast cancer that is refractory to other chemotherapies. EXPERIMENTAL DESIGN: Data from one randomized multicenter trial comparing combination therapy with ixabepilone and capecitabine to capecitabine alone were analyzed for support of the combination therapy indication. For monotherapy, a single-arm trial of ixabepilone was analyzed. Supporting data came from an additional single-arm combination therapy study and two single-arm monotherapy studies. RESULTS: In patients with metastatic or locally advanced breast cancer who had disease progression on or following an anthracycline and a taxane, ixabepilone plus capecitabine showed an improvement in progression-free survival compared with capecitabine alone {median progression-free survival, 5.7 [95% confidence interval (95% CI), 4.8-6.7] versus 4.1 (95% CI, 3.1-4.3) months, stratified log-rank P < 0.0001; hazard ratio, 0.69 (95% CI, 0.58-0.83)}. As monotherapy for patients who had disease progression on or following an anthracycline, a taxane, and capecitabine, ixabepilone as monotherapy showed a 12% objective response rate by independent blinded review and 18% by investigator assessment. The major toxicities from ixabepilone therapy were peripheral neuropathy and myelosuppression, particularly neutropenia. CONCLUSIONS: On October 16, 2007, the Food and Drug Administration approved ixabepilone for injection in combination with capecitabine or as monotherapy for the treatment of patients with advanced breast cancer who have experienced disease progression on previous chemotherapies.     

Differences in regional blood volume during a 28-day period of abstinence in chronic cannabis smokers.

Cerebral blood volume (CBV) studies have provided important insight into the effects of illicit substances such as cannabis. The present study examined changes in regional blood volume in the frontal and temporal lobe, and the cerebellum during 28 days of supervised abstinence from cannabis. Dynamic susceptibility contrast MRI (DSCMRI) data were collected on 15 current, long-term cannabis users between 6 and 36 h after the subjects' last reported cannabis use (Day 0), and again after 7 and 28 days of abstinence. Resting state CBV images were also acquired on 17 healthy comparison subjects. The present findings demonstrate that at Day 7, cannabis users continued to display increased blood volumes in the right frontal region, the left and right temporal regions, and the cerebellum. However, after 28 days of abstinence, only the left temporal area and cerebellum showed significantly increased CBV values in cannabis users. These findings suggest that while CBV levels begin to normalize with continued abstinence from cannabis, specifically in frontal areas, other temporal and cerebellar brain regions show slower CBV decreases.     

Intensive short course chemotherapy for tuberculous meningitis.

This nonrandomized, open clinical investigation of tuberculous meningitis evaluated 53 children with Stage I (n = 8), Stage II (n = 29) and Stage III (n = 16) disease. The overall mortality was 20.8% (11 of 53) with a rate of sequelae of 35.7% (15 of 42) in survivors reflecting the advanced stages of children at diagnosis. Various combinations of standard antituberculous drugs including isoniazid, rifampin, pyrazinamide, streptomycin and ethambutol were given. Three treatment durations used during various time periods were evaluated: 12, 9 and 6 months with only the 6-month regimen receiving pyrazinamide (PZA). This prospective evaluation demonstrated that: (1) severe disease at presentation is highly associated with early mortality (P less than 0.05), regardless of drug regimen; and (2) intensive short course chemotherapy (6 months) with PZA, regardless of stage of disease at presentation, is more efficacious than longer course therapy (9 or 12 months) without PZA in preventing total negative outcomes and sequelae (P less than 0.05). This study demonstrates that a 6-month regimen containing PZA can be used in treating children with tuberculous meningitis.     

COL2A1 exon 2 mutations: relevance to the Stickler and Wagner syndromes

AIMS: To compare the clinical and molecular genetic features of two phenotypically distinct subgroups of families with type 1 Stickler syndrome. BACKGROUND: Stickler syndrome (hereditary arthro-ophthalmopathy, McKusick Nos 108300 and 184840) is a dominantly inherited disorder of collagen connective tissue, resulting in an abnormal vitreous, myopia, and a variable degree of orofacial abnormality, deafness, and arthropathy. Stickler syndrome is the commonest inherited cause of rhegmatogenous retinal detachment in childhood with a risk of giant retinal tear (GRT) which is commonly bilateral and a frequent cause of blindness. METHOD: Pedigrees were identified from the vitreoretinal service database and subclassified according to vitreoretinal phenotype. Ophthalmic, skeletal, auditory, and orofacial features were assessed. Linkage analysis was carried out with markers for the candidate genes COL2A1, COL11A1, and COL11A2. The COL2A1 gene was amplified as five overlapping PCR products. Direct sequencing of individual exons identified mutations. RESULTS: Eight families exhibiting the type 1 vitreous phenotype were studied. Seven were consistent for linkage to COL2A1, with lod scores ranging from 2.1 to 0.3. In most instances linkage to COL11A1 and COL11A2 could be excluded. One family was analysed without prior linkage analysis. Three of the families exhibited a predominantly ocular phenotype with minimal or absent systemic involvement and were found to have mutations in exon 2 of COL2A1. Five other pedigrees with an identical ocular phenotype plus orofacial, auditory, and articular involvement had mutations in others regions of the COL2A1 gene. None of the pedigrees exhibited the characteristic lenticular, retinal pigment epithelial, or choroidal changes seen in Wagner syndrome. CONCLUSIONS: These data confirm that type 1 Stickler syndrome is caused by mutations in the gene encoding type II collagen (COL2A1). In addition, data are submitted showing that mutations involving exon 2 of COL2A1 are characterised by a predominantly ocular variant of this disorder, consistent with the major form of type II procollagen in non-ocular tissues having exon 2 spliced out. Such patients are all at high risk of retinal detachment. This has important implications for counselling patients with regard to the development of systemic complications. It also emphasises the importance and reliability of the ophthalmic examination in the differential diagnosis of this predominantly ocular form of Stickler syndrome from Wagner's vitreoretinopathy.     

Peptic Ulcer/Stricture After Gastric Bypass: A Comparison of Technique and Acid Suppression Variables

Background: Mason's original animal experiments on the gastric bypass (GBP) showed little acid production in the gastric pouch, a finding confirmed in humans. Despite this, GBP in humans is associated with an incidence of ulcer/stricture (U/S) at the gastrojejunostomy of 3 to 20%, with both acid secretion and staple-line dehiscence considered important risk factors or etiologies. Our series of GBP patients was reviewed to determine what technical or management factors, if any, were associated with U/S. Methods: All patients undergoing first time GBP at Dartmouth-Hitchcock Medical Center by one surgeon from June 1991 until June 2000 were reviewed. The incidence of U/S as confirmed on upper endoscopy was determined by retrospective chart review. The technique of surgery, frequency of acid suppressive therapy at discharge, postoperative day of U/S diagnosis by endoscopy, length of follow-up with a member of the multidisciplinary bariatric team, and incidence of staple-line dehiscence were tabulated. Results: 158 patients (72% female, mean BMI 53, mean age 42) underwent GBP.Two gastric stapling methods were used to create the gastric pouch: 4-rows (136 patients) and 8-rows (22 patients). No other technical feature was adjusted in the series. The two patient groups were similar in gender, age, and BMI. Acid suppressive therapy at the time of discharge was similar in each group with U/S (4-rows 64% and 8-rows 50%, p=0.5). U/S developed in 12 (55%) of the 8-row group and in 14 (10%) of the 4-row group (p < 0.001). U/S typically occurred within the first 2 months postoperatively (mean 48 days, SD 40). No patients in our series developed a staple-line dehiscence. Conclusion: U/S occur in the first few months following GBP.Twice the number of gastric staple-lines is associated with over five times the incidence of U/S, whereas post-discharge acid suppressive therapy is not predictive of U/S. Thus, a technique performed to decrease the risk of staple-line breakdown was associated with a much higher incidence of U/S. Staple-line dehiscence is not the etiology of this condition.Therefore, U/S after GBP does not appear to be explained by acid injury. We speculate that local, tissue injury related factors may be more responsible, a speculation that invokes a novel pathophysiologic mechanism for U/S formation following gastrojejunostomy.