175 research outputs found
The Association between Reduction in PM2.5 and Improvement in Cardiovascular Mortality Rates
We examined the association between county-level change in PM2.5 and change in cardiovascular mortality rate before and after implementation of the 1997 annual PM2.5 National Ambient Air Quality Standards. We examined how the association varied between counties stratified by attainment designation and by design values used in the designation process to characterize air quality. We used linear regression and difference-in-difference models, adjusted for sociodemographic confounders. Across 619 counties in the study, there were 1.10 (95% CI 0.37, 1.82) fewer deaths per year per 100,000 people per 1 ”g/m3 PM2.5 decrease. Improvements in air quality and morality rates were greater in nonattainment counties and in the counties with the highest design values, while attainment counties and those with the lowest design values had greater decrease in mortality rate per unit decrease in PM2.5; however, the differences between estimates changes in mortality rates were not statistically significant.Master of Scienc
A retrospective analysis of longitudinal changes in bone mineral content in cystic fibrosis
Background:
We aimed to describe the longitudinal changes in bone mineral content and influencing factors, in children with cystic fibrosis (CF).
Methods:
One hundred children (50 females) had dual X-ray absorptiometry (DXA) performed. Of these, 48 and 24 children had two to three scans, respectively over 10 years of follow-up. DXA data were expressed as lumbar spine bone mineral content standard deviation score (LSBMCSDS) adjusted for age, gender, ethnicity and bone area. Markers of disease, anthropometry and bone biochemistry were collected retrospectively.
Results:
Baseline LSBMCSDS was >0.5 SDS in 13% children, between â0.5; 0.5 SDS, in 50% and â€â0.5 in the remainder. Seventy-eight percent of the children who had baseline LSBMCSDS >â0.5, and 35% of the children with poor baseline (LSBMCSDS<â0.5), showed decreasing values in subsequent assessments. However, mean LS BMC SDS did not show a significant decline in subsequent assessments (â0.51; â0.64; â0.56; p=0.178). Lower forced expiratory volume in 1 s percent (FEV1%) low body mass index standard deviation scores (BMI SDS) and vitamin D were associated with reduction in BMC.
Conclusions:
Bone mineral content as assessed by DXA is sub-optimal and decreases with time in most children with CF and this study has highlighted parameters that can be addressed to improve bone health
An Analysis of Drug Dissolution Rates in the USP 24 Type 2 Apparatus
This paper applies boundary layer theory to the process of drug dissolution in the USP 24, Type 2 Apparatus. The mass transfer rate from the top flat surface of a compact in various positions within the device is evaluated by means of a Pohlhausen integral method
Defining breast cancer awareness and identifying barriers to breast cancer awareness for women with an intellectual disability: A review of the literature
Introduction: Incidence rates for developing breast cancer are similar for women regardless of intellectual ability. However, women with an intellectual disability present with advanced breast cancers, which often have a poor prognosis. Method: A structured narrative review of the literature was performed to explore the concepts of breast awareness and breast cancer awareness and subsequently, identify barriers to breast cancer awareness encountered by women with an intellectual disability. Results: A total of 22 studies involving people with varying levels of intellectual disability informed this review. The barriers to breast cancer awareness encountered by women with an intellectual disability include: lack of their understanding, the role of the carer and literacy issues. Conclusion: Identifying the barriers to breast cancer awareness for women with an intellectual disability will help to facilitate breast cancer awareness which has the potential to result in better long-term outcomes through an early diagnosis of breast cancer
Solid-state characterization of novel active pharmaceutical ingredients: Cocrystal of a salbutamol hemiadipate salt with adipic acid (2:1:1) and salbutamol hemisuccinate salt.
The production of salt or cocrystalline forms is a common approach to alter the physicochemical properties of pharmaceutical compounds. The goal of this work was to evaluate the impact of anion choice (succinate, adipate, and sulfate) on the physicochemical characteristics of salbutamol forms. Novel crystals of salbutamol were produced by solvent evaporation: a cocrystal of salbutamol hemiadipate with adipic acid (salbutamol adipate, SA), salbutamol hemisuccinate tetramethanolate (SSU.MeOH), and its desolvated form (SSU). The crystalline materials obtained were characterized using thermal, X-ray, nuclear magnetic resonance, Fourier transform infrared spectroscopy, dynamic vapor sorption (DVS), and elemental analysis. The crystal forms of SA and SSU.MeOH were determined to be triclinic, (PÄ«), and monoclinic, (P21/n), respectively. DVS analysis confirmed that SSU and SA do not undergo hydration under increased relative humidity. Both thermal and elemental analyses confirmed the stoichiometry of the salt forms. The aqueous solubilities of SA and SSU were measured to be 82â± 2âmg/mL (pH 4.5â± 0.1) and 334â± 13âmg/mL (pH 6.6â± 0.1), respectively. Measured values corresponded well with the calculated pH solubility profiles. The intrinsic dissolution rate of cocrystallized SA was approximately four times lower than that of SSU, suggesting its use as an alternative to more rapidly dissolving salbutamol sulfate
Preventing Eviction and Housing Loss: Taking Advantage of a One Health Approach and the Human-Companion Animal Bond
Impact of process variables on the micromeritic and physicochemical properties of spray-dried microparticles, part II: physicochemical characterisation of spray-dried materials
YesObjectivesâ In this work we investigated the residual organic solvent content and physicochemical properties of spray-dried chlorothiazide sodium (CTZNa) and potassium (CTZK) salts.
Methodsâ The powders were characterised by thermal, X-ray diffraction, infrared and dynamic vapour sorption (DVS) analyses. Solvent levels were investigated by KarlâFischer titration and gas chromatography.
Key findingsâ Spray-drying from water, methanol (MeOH) and mixes of MeOH and butyl acetate (BA) resulted in amorphous microparticles. The glass transition temperatures of CTZNa and CTZK were âŒ192 and âŒ159°C, respectively. These materials retained their amorphous nature when stored at 25°C in dry conditions for at least 6 months with no chemical decomposition observed. DVS determined the critical relative humidity of recrystallisation of CTZNa and CTZK to be 57% RH and 58% RH, respectively. The inlet temperature dependant oxidation of MeOH to formaldehyde was observed; the formaldehyde was seen to deposit within the amorphous matrix of spray-dried product. Spray-drying in the open blowing mode coupled with secondary drying resulted in a three-fold reduction in residual BA (below pharmacopoeial permitted daily exposure limit) compared to spray-drying in the closed mode.
Conclusionsâ Experiments showed that recirculation of recovered drying gas increases the risk of deposition of residual solvents in the spray-dried product.The Irish Research Council for Science and Engineering Technology (IRCSET), the Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number (07/SRC/B1158) and the Irish Drug Delivery Research Network, a Strategic Research Cluster grant (07/SRC/B1154) under the National Development Plan co-funded by EU Structural Funds and Science Foundation Ireland
An Analysis of Drug Dissolution Rates in the USP 24 Type 2 Apparatus
This paper applies boundary layer theory to the process of drug dissolution in the USP 24, Type 2 Apparatus. The mass transfer rate from the top flat surface of a compact in various positions within the device is evaluated by means of a Pohlhausen integral method
Impact of process variables on the micromeritic and physicochemical properties of spray-dried porous microparticles, part I: introduction of a new morphology classification system
YesObjectives This work investigated the impact of spray drying variables such as feedconcentration, solvent composition and the drying mode, on the micromeriticproperties of chlorothiazide sodium (CTZNa) and chlorothiazide potassium(CTZK).Methods Microparticles were prepared by spray drying and characterised usingthermal analysis, helium pycnometry, laser diffraction, specific surface area analysisand scanning electron microscopy.Key findings Microparticles produced under different process conditions pre-sented several types of morphology.To systematise the description of morphology ofmicroparticles, a novel morphology classification system was introduced. The shapeof the microparticles was described as spherical (1) or irregular (2) and the surfacewas classified as smooth (A) or crumpled (B). Three classes of morphology of micro-particles were discerned visually: class I, non-porous; classes II and III, comprisingdiffering types of porosity characteristics. The interior was categorised as solid/continuous (a), hollow (b), unknown (g) and hollow with microparticulate content(d). Nanoporous microparticles of CTZNa and CTZK, produced without recircula-tion of the drying gas, had the largest specific surface area of 72.3 and 90.2 m2/g,respectively, and presented morphology of class 1BIIIa.Conclusions Alteration of spray drying process variables, particularly solvent com-position and feed concentration can have a significant effect on the morphology ofspray dried microparticulate products. Morphology of spray dried particles may beusefully described using the morphology classification system.The Irish Research Council for Science and Engineering Technology (IRCSET), the Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number [07/SRC/B1158] and the Irish Drug Delivery Research Network, a Strategic Research Cluster grant (07/SRC/B1154) under the National Development Plan co-funded by EU Structural Funds and Science Foundation Ireland
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