DART,a platform for the creation and registration of cone beam digital tomosynthesis datasets

Digital tomosynthesis is an imaging modality that allows for tomographic reconstructions using only a fraction of the images needed for CT reconstruction. Since it offers the advantages of tomographic images with a smaller imaging dose delivered to the patient, the technique offers much promise for use in patient positioning prior to radiation delivery. This paper describes a software environment developed to help in the creation of digital tomosynthesis image sets from digital portal images using three different reconstruction algorithms. The software then allows for use of the tomograms for patient positioning or for dose recalculation if shifts are not applied, possibly as part of an adaptive radiotherapy regimen.     

Evaluation of intake fractions for different subpopulations due to primary fine particulate matter (PM2.5) emitted from domestic wood combustion and traffic in Finland

Domestic wood combustion and traffic are the two most significant primary fine particulate matter (PM_2.5) emission source categories in Finland. We estimated emission–exposure relationships for primary PM_2.5 emissions from these source categories using intake fractions (iF), which describes the fraction of an emission that is ultimately inhaled by a target population. The iFs were calculated for four different emission source subcategories in Finland in 2000: (1) domestic wood combustion in residential buildings, (2) domestic wood combustion in recreational buildings, (3) traffic exhaust and wear emissions, and (4) traffic resuspension emissions. The iFs were estimated for both total population and for subpopulations with different gender, age, and educational status. Primary PM_2.5 emissions were based on the Finnish Regional Emission Scenario model and the dispersion of particles was calculated using the Urban Dispersion Modeling system of Finnish Meteorological Institute. Both emissions and dispersion were estimated on a 1 km spatial resolution. The iFs for primary PM_2.5 emissions from (1) residential and (2) recreational buildings were 3.4 and 0.6 per million, respectively. The corresponding iF for (3) traffic exhaust and wear and (4) traffic resuspension emissions were 9.7 and 9.5 per million, respectively. The differences in population-weighted outdoor concentrations were significant between subpopulations with different educational status so that people with higher education were exposed more to traffic-related PM_2.5.     

Patient perspectives on improving oral health-care practices among people living with HIV/AIDS

This qualitative study explored the impact on oral health-care knowledge, attitudes, and practices among 39 people living with HIV/AIDS (PLWHA) participating in a national initiative aimed at increasing access to oral health care. Personal values and childhood dental experiences, beliefs about the importance of oral health in relation to HIV health, and concerns for appearance and self-esteem were found to be determinants of oral health knowledge and practice. Program participation resulted in better hygiene practices, improved self-esteem and appearance, relief of pain, and better physical and emotional health. In-depth exploration of the causes for these changes revealed a desire to continue with dental care due to the dental staff and environmental setting, and a desire to maintain overall HIV health, including oral health. Our findings emphasize the importance of addressing both personal values and contextual factors in providing oral health-care services to PLWHA.     

Identification of a new antinociceptive alkaloid isopropyl N-methylanthranilate from the essential oil of Choisya ternata Kunth

Ethnopharmacological relevance

Mexican people employed infusion of leaves of Choisya ternata Kunth for their antispasmodic and “simulative properties”.

Aim of the study

In the present study the detailed GC and GC-MS analyses of the essential oil of Choisya ternata Kunth (Rutaceae) were performed. The presence of a minor constituent isopropyl N-methylanthranilate (1) was revealed among other identified volatiles. A synthesis of 1 was undertaken in order to corroborate this find and obtain gram quantities that would allow the testing of its biological activity (peripheral and central antinociceptive activity).

Materials and methods

The oils were investigated by GC and GC-MS. Synthesized compounds were spectrally characterized (UV-Vis, IR, 1D and 2D NMR, MS). The obtained synthetic samples of compounds were assayed for peripheral and central antinociceptive activity in two models (effects on acetic acid induced writhing in mice and the hot plate test for nociception).

Results

Detailed GC and GC-MS analyses of the essential oil of Choisya ternata Kunth (Rutaceae) among 157 other identified volatiles revealed the presence of a minor constituent isopropyl N-methylanthranilate (1). Compound 1, named ternanthranin, is therefore detected as a natural product for the first time with a very restricted occurrence (samples of several citrus oils were screened for the presence of 1). The antinociceptive activities were assayed for ternanthranin, the two other synthetic analogs, methyl and propyl N-methylanthranilate, as well as the essential oil and the crude ethanol extract of the leaves. The results clearly demonstrate a very high (even significant at 0.3 mg/kg) dose dependent activity for the anthranilates (and the extracts). Isopropyl N-methylanthranilate showed the highest, while methyl N-methylanthranilate showed the lowest activity (with the methyl ester at 3 mg/kg still better than acetylsalicylic acid, at 200 mg/kg, in the first, or comparable with morphine, at 5 mg/kg, in the second test).

Conclusion

This study once again revealed that detailed investigations of plant species with ethnopharmacologically documented activity may yield new natural compounds—a new alkaloid (ternanthranin), a volatile simple anthranilate that can be considered responsible for the antinociceptive activity of the crude plant extracts.     

Early Benefit Assessments in Oncology in Germany: How Can a Clinically Relevant Endpoint Not Be Relevant to Patients?

After 4 years of early benefit assessment (EBA) in Germany, it is becoming evident that the Federal Joint Committee (FJC) frequently considers well-established clinical endpoints as not being relevant to patients. Focusing on assessments of oncology medicines, we analysed the FJC’s view on primary endpoints and compared it with the approach used by regulatory authorities. Mortality data were accepted by both stakeholders. Whereas regulatory authorities accepted primary morbidity endpoints such as progression-free survival and response rates, the FJC mostly excluded these from its assessments. Health-related quality of life (HRQoL) data have been poorly reflected in the approval process; for EBAs, those data have rarely impacted on benefit ratings. We argue that agreement between regulatory authorities and the FJC is required regarding primary study endpoints that are relevant to patients, and that clarification of acceptable endpoints by the FJC, especially in the morbidity domain, has to be provided. Moreover, in order to fully acknowledge the benefit of a new medicinal product, mortality, morbidity and HRQoL should be weighted differentially, according to the condition.     

Spectral analysis of physiological brain pulsations affecting the BOLD signal

Physiological pulsations have been shown to affect the global blood oxygen level dependent (BOLD) signal in human brain. While these pulsations have previously been regarded as noise, recent studies show their potential as biomarkers of brain pathology. We used the extended 5 Hz spectral range of magnetic resonance encephalography (MREG) data to investigate spatial and frequency distributions of physiological BOLD signal sources. Amplitude spectra of the global image signals revealed cardiorespiratory envelope modulation (CREM) peaks, in addition to the previously known very low frequency (VLF) and cardiorespiratory pulsations. We then proceeded to extend the amplitude of low frequency fluctuations (ALFF) method to each of these pulsations. The respiratory pulsations were spatially dominating over most brain structures. The VLF pulsations overcame the respiratory pulsations in frontal and parietal gray matter, whereas cardiac and CREM pulsations had this effect in central cerebrospinal fluid (CSF) spaces and major blood vessels. A quasi‐periodic pattern (QPP) analysis showed that the CREM pulsations propagated as waves, with a spatiotemporal pattern differing from that of respiratory pulsations, indicating them to be distinct intracranial physiological phenomenon. In conclusion, the respiration has a dominant effect on the global BOLD signal and directly modulates cardiovascular brain pulsations.     

The effect of Er,Cr:YSGG laser and air abrasion on shear bond strength of a fissure sealant to enamel

PurposeThe authors conducted an in vitro study to evaluate the shear bond strength of a fissure sealant to enamel pretreated with erbium, chromium: yttrium, scandium, gallium, garnet (Er, Cr: YSGG) laser or air abrasion followed by acid etching.MethodsThe authors sectioned extracted sound premolars mesiodistally and used the buccal and lingual surfaces for experimental analysis. They divided specimens randomly into three groups of 15 each according to the enamel surface pretreatment methods: group A, 37 percent phosphoric acid; group B, air abrasion followed by acid etching with 37 percent phosphoric acid; group C, irradiation with Er, Cr: YSGG laser followed by acid etching with 37 percent phosphoric acid. After applying a bonding system, the authors bonded cylinders of sealant to the enamel surfaces by using transparent gelatin tubes (0.7 millimeter in diameter and 1 mm in height) and then polymerized them. They stored all specimens in distilled water at 37°C for 24 hours. They tested shear bond strength by using a universal testing machine with a crosshead speed of 0.5 mm per second. The authors analyzed the data by means of one-way analysis of variance and Tukey-Kramer post hoc tests (α = .05).ResultsThe bond strength of group B specimens was statistically higher than those of group A and group C specimens (P < .05). The authors found no statistically significant differences in shear bond strength between surfaces treated with Er, Cr: YSGG laser and those treated with acid etching alone (P > .05).ConclusionPretreatment of enamel surfaces with air abrasion increased the bond strength of fissure sealant, but pretreatment with Er, Cr: YSGG laser did not increase the effectiveness of conventional acid etching of enamel in sealant bonds.     

Infection with versus Exposure to Taenia solium: What Do Serological Test Results Tell Us?

Taenia solium cysticercosis is an endemic zoonosis in many developing countries. Serological tests are the most appropriate diagnostic tools to understand the transmission dynamics of the parasite, but the performances of these methods in such a setting are not known. A south Ecuadorian human population living in an endemic area was tested using three common serological tests. Because none of them is a gold standard, a Bayesian Latent Class analysis was used to estimate the test characteristics. Two definitions of a case were considered to differentiate between prevalence of current infection and prior exposure to the parasite. Differences between the performances of the same test in function of the definition of a case were observed. This study shows that test results and prior information should be interpreted carefully in a Bayesian analysis framework, particularly when the latter is based on clinical studies.     

Decomposing malnutrition inequalities between Scheduled Castes and Tribes and the remaining Indian population

Objective. In India, Scheduled Castes and Scheduled Tribes (ST/SC) have been excluded from Hindu society for thousands of years. Together, they comprise over 24% of India's population and still suffer worse health conditions compared to the rest of the Indian population. This paper decomposes the gap in child malnutrition between the ST/SC and the remaining Indian population, looking at both the ST/SC's disadvantageous distribution of health determinants and possible discriminatory or behavioral differences.

Design and setting. A Blinder–Oaxaca decomposition was applied to decompose the gap in children's average height-for-age z scores, using data from the 1998/1999 Indian Demographic Health Survey.

Results. The gap was found to be primarily caused by the ST/SC's lower wealth, education and use of health care services, but also differences in the effects of health determinants played an important role. It was found that within rural areas ST/SC are not necessarily located further from educational and health care facilities.

Conclusions. The use of Oaxaca type decomposition can be very useful when studying ethnic inequalities in health as it explicitly allows for discriminatory or behavioral effects. The results did not point to discrimination against ST/SC regarding health care or education. However, in the quest to increase health care use and education among ST/SC, policy makers will have to take into account all the barriers to these services, including those related to cultural sensitivity and acceptability.