Permanent inflation of detachable balloons with a low-viscosity, hydrophilic polymerizing system

A polymer system was developed for use in permanent inflation of detachable balloons, to avoid long-term reliance on the integrity of balloon shells or valve mechanisms. This system is based on 2-hydroxy-ethyl methacrylate (HEMA) as the monomer, in combination with a cross-linking agent and a water-soluble curing system. The low-viscosity, hydrophilic mixture can be exchanged through a small-bore catheter into a detachable balloon and polymerizes in 40-60 minutes at body temperature. Partially polymerized HEMA can cause vascular occlusion; hence, careful timing of balloon detachment is required. The evolution of the radiographic appearance of HEMA-filled balloons is predictable. The balloons remain radiopaque on plain radiographs as long as the balloon shell and valve mechanisms are competent. After rupture of the shell or failure of the valve mechanism, the balloons become invisible on plain radiographs but remain hyperattenuating on computed tomography scans.     

Carcinoma of the breast: detection with MR imaging versus xeromammography

Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer.     

The larger bronchi in cryptogenic fibrosing alveolitis: a morphometric study

In a morphometric study of the main, lobar, and segmental bronchi of the left lung in nine cases of cryptogenic fibrosing alveolitis the quantity of gland was found to be significantly greater than in a group of normal controls, and similar to that of a group of patients with chronic bronchitis. The quantity of muscle was also increased, amounts in the segmental bronchi being higher than in the bronchitic patients. The cause of these changes is uncertain, but they seem likely to be due to proximal extension of repeated and persistent infection of the lung parenchyma.     

3-Methylcholanthrene and other aryl hydrocarbon receptor agonists directly activate estrogen receptor alpha

3-Methylcholanthrene (3MC) is an aryl hydrocarbon receptor (AhR) agonist, and it has been reported that 3MC induces estrogenic activity through AhR-estrogen receptor alpha (ER alpha) interactions. In this study, we used 3MC and 3,3',4,4',5-pentachlorobiphenyl (PCB) as prototypical AhR ligands, and both compounds activated estrogen-responsive reporter genes/gene products (cathepsin D) in MCF-7 breast cancer cells. The estrogenic responses induced by these AhR ligands were inhibited by the antiestrogen ICI 182780 and by the transfection of a small inhibitory RNA for ER alpha but were not affected by the small inhibitory RNA for AhR. These results suggest that 3MC and PCB directly activate ER alpha, and this was confirmed in a competitive ER alpha binding assay and in a fluorescence resonance energy transfer experiment in which PCB and 3MC induced CFP-ER alpha/YFP-ER alpha interactions. In a chromatin immunoprecipitation assay, PCB and 3MC enhanced ER alpha (but not AhR) association with the estrogen-responsive region of the pS2 gene promoter. Moreover, in AhR knockout mice, 3MC increased uterine weights and induced expression of cyclin D1 mRNA levels. These results show that PCB and 3MC directly activate ER alpha-dependent transactivation and extend the number of ligands that activate both AhR and ER alpha.     

Treatment of intracerebral arteriovenous malformations with isobutyl 2- cyanoacrylate: initial clinical experience

From November 1976 to September 1979, 46 patients with intracranial arteriovenous malformations or fistulas participated in a clinical study using isobutyl 2-cyanoacrylate (IBCA), with tantalum, for palliative or preoperative occlusion of the blood supply to the abnormalities. Although failure to obtain satisfactory position of a functioning microcatheter precluded deposition of IBCA 10 times, a total of 51 of a possible 62 feeding vessels were occluded with the tantalum-impregnated glue. The technique, results, and complications are discussed in light of the clinical follow-up, which varied from 12 to 48 months.     

Risks of human conotruncal heart defects associated with 32 single nucleotide polymorphisms of selected cardiovascular disease-related genes

Investigating possible genetic polymorphisms and gene-environment interactions in the etiology of human conotruncal defects is a prudent research approach. In this study we explore gene-only and gene-environment effects of 32 single nucleotide polymorphisms (SNPs) on conotruncal defect risks. The genes bearing these SNPs participate in one of five pathogenetic processes, homocysteine metabolism, coagulation, cell-cell interaction, inflammatory response, and blood pressure regulation. We used DNA samples and data from a California population-based case-control interview study (1987-1988 birth cohort). We employed a multilocus allele-specific hybridization assay. Allelic variants were determined by genotyping 155 infants with conotruncal defects (cases) and 437 infants without malformations (controls). Among the 32 SNPs, four were associated with odds ratios of 2 or more, and two with odds ratios of 0.5 or less. The four SNPs were F2 G20210A (prothrombin) with an odds ratio of 2.5 (95% confidence interval; 0.9-7.0), F7 promoter (-323) 10-bp del/ins with an odds ratio of 2.3 (0.8-6.8), ITGB3 leu33pro (platelet glycoprotein IIIa) with an odds ratio of 2.2 (0.9-5.7), and NPPA T2238C (atrial natriuretic precursor peptide) with an odds ratio of 2.9 (0.8-10.1). Two SNPs were associated with decreased risks: TNF (tumor necrosis factor, G (-376A)) and ADD1 gly460trp (alpha adducin) with odds ratios of 0.5 (0.1-2.3) and 0.5 (0.2-1.9), respectively. Analyses that investigated a potential gene-nutrient interaction between maternal periconceptional vitamin use and MTHFR genotypes did not indicate that the CT or TT genotype contributed to conotruncal defect risk in infants even in the absence of maternal use of multivitamin supplements with folic acid. Analyses that investigated a potential interaction on risk between NOS3 genes and maternal cigarette smoking, revealed some evidence for higher risk of conotruncal defects in infants whose mothers smoked cigarettes periconceptionally and who had one of the variant alleles for NOS3 A(-922G) or NOS3 glu298asp compared to those infants whose mothers did not smoke and whose genotypes were wild-type. Our results provide some support for involvement of genetic variation of biologically relevant candidate genes for some birth defects whose pathogenesis may be related to altered vascular tone or integrity. In particular, NPPA appears to be a good candidate gene for conotruncal defects and warrants further investigation.     

Application of classic utilities to published pediatric cost-utility studies

ObjectiveEconomic analyses, such as cost-utility analyses (CUAs), are dependent on the quality of the data used. Our objective was to test how health utility values (measurements of patient preference) assessed by recommended methods (classic utilities) would impact the conclusions in published pediatric CUAs.MethodsClassic utilities for pediatric health states were obtained by recommended utility assessment methods, time trade-off, and standard gamble in 4016 parent interviews. To test the impact of these utilities on published studies, we obtained a sample of published pediatric CUAs by searching Medline, EMBASE, EconLit, Health Technology Assessment Database, Cochrane Database on Systematic Reviews, Database of Abstracts of Reviews of Effects, and the Cost Effective Analysis (CEA) Registry at Tufts Medical Center, using search terms for cost-utility analysis. Articles were included when results were presented as cost per quality adjusted life-years (QALYs), the interventions were for children <18 years of age and included at least one of the following health states: attention deficit hyperactivity disorder, asthma, gastroenteritis, hearing loss, mental retardation, otitis media, seizure disorder, or vision loss. Studies that did not include these or equivalent health states were excluded. For each CUA, we determined utilities (values for patient preference), the utility assessment method used, and presence of one-way sensitivity analyses (SAs) on utilities. When one-way SAs were conducted, we determined if using our classic utilities would change the result of the CUA. When an SA was not presented, we determined if using our classic utilities would tend to support or not support the published conclusions.ResultsWe evaluated 39 articles. Eighteen articles presented results of one-way SAs on utilities. Seven articles presented SAs over a range that included our classic utilities. In 4 of the 7, using classic utilities would change the conclusion of the study. For the 32 articles where no one-way SA were presented (n = 21), or where the classic utilities fell outside the range tested (n =11), a change to classic utility would tend against the study conclusion in 12 articles (31%).ConclusionsMore than a third of published CUA studies could change if pediatric utilities obtained by recommended, classic methods were used. One-way SAs on utilities are often not presented, making comparison between studies challenging.