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Aim: Although caring relatives of people with dementia are a mainstay of many care systems, the availability of support services for them within the municipal community shows deficiencies. Adopting the Theoretical Domains Framework (TDF) this study aims to investigate 1) which of the TDF domains adapted to gerontology show up in public dialogue, and 2) the results that public dialogues produce in terms of support services for caring relatives. Subject and methods: The data consists of town hall meetings and focus groups from 14 municipal communities in Germany. Participants were caring relatives and stakeholders of the communities. A qualitative content analysis was conducted, focusing on the assessment of three TDF domains, namely knowledge, goals, and sociopolitical contextas well as outcomes of care optimisation. Results: With regard to domain knowledge, it was evident that in every community there were actors aware of the situation and relevance of carers and their relatives. Only some actors mentioned goalsfor optimising the care of the target group. The sociopolitical contextis often addressed through statements about incomplete requirements. Conclusion: Overall, a relation between the discussion about the domains in public dialogues and changes in supporting carers of people with dementia can be assumed. The results indicate that an increased discussion about the domains within town hall meetings influences the actors and their statements with regard to the improvement of support services for caring relatives of people with dementia. Since the domains were not developed exclusively for the outlined context, this approach can also be applied to other areas of care.

Improved resolution of molecular diagnostic technologies enabled detection of smaller sized exonic level copy-number variants (CNVs). The contribution of CNVs to autosomal recessive (AR) conditions may be better recognized using a large clinical cohort.

Small noncoding RNAs are central regulators of genome activity and stability. Their regulatory function typically involves sequence similarity with their target sites, but understanding the criteria by which they specifically recognize and regulate their targets across the genome remains a major challenge in the field, especially in the face of the diversity of silencing pathways involved. The dominance hierarchy among self-incompatibility alleles in Brassicaceae is controlled by interactions between a highly diversified set of small noncoding RNAs produced by dominant S-alleles and their corresponding target sites on recessive S-alleles. By controlled crosses, we created numerous heterozygous combinations of S-alleles in Arabidopsis halleriand developed an real-time quantitative PCR assay to compare allele-specific transcript levels for the pollen determinant of self-incompatibility (SCR). This provides the unique opportunity to evaluate the precise base-pairing requirements for effective transcriptional regulation of this target gene. We found strong transcriptional silencing of recessive SCRalleles in all heterozygote combinations examined. A simple threshold model of base pairing for the small RNA–target interaction captures most of the variation in SCRtranscript levels. For a subset of S-alleles, we also measured allele-specific transcript levels of the determinant of pistil specificity (SRK), and found sharply distinct expression dynamics throughout flower development between SCRand SRK. In contrast to SCR, both SRKalleles were expressed at similar levels in the heterozygote genotypes examined, suggesting no transcriptional control of dominance for this gene. We discuss the implications for the evolutionary processes associated with the origin and maintenance of the dominance hierarchy among self-incompatibility alleles.

Ein Teilprojekt der von der Deutschen Bischofskonferenz in Auftrag gegebenen Studie »Sexueller Missbrauch an Minderjährigen durch katholische Priester, Diakone und männliche Ordensangehörige im Bereich der Deutschen Bischofskonferenz« befasst sich mit der Analyse von Strafakten. Es wurden Strafverfahren wegen sexueller Missbrauchsdelikte gegen Minderjährige durch Kleriker der katholischen Kirche und durch Mitglieder anderer Institutionen, wie z. B. Schulen, ausgewertet. In diesem Beitrag wird untersucht, ob die besonderen Rahmenbedingungen in der katholischen Kirche, insbesondere das Kirchenrecht und der Klerikalismus, einen Einfluss auf Taten, Täter und institutionelle Reaktionen bei Delikten des sexuellen Missbrauchs von Minderjährigen haben. Die Analyse ergab, dass die Besonderheiten in der katholischen Kirche mit spezifischen Tat- und Tätermerkmalen korrespondierten und die Institutionen unterschiedlich auf Missbrauchsvorwürfe reagierten. Obwohl das Normensystem, das einen sexuellen Missbrauch verhindern soll, in der katholischen Kirche viel ausgeprägter ist als in anderen Institutionen, sind keine Unterschiede im Verhalten der Akteure ersichtlich.

The purpose of this study is to develop a classification system utilizing milligram amounts of the compound for physical stability ranking of amorphous pharmaceuticals, which can be used as an early risk assessment tool for amorphous solid dispersion formulations. Simple thermal analysis utilizing a differential scanning calorimeter is used to characterize amorphous pharmaceuticals with respect to their molecular mobility and configurational entropy. Molecular mobility and configurational entropy are considered as two critical factors in determining the physical stability of amorphous phases. Theoretical arguments and numerical simulations suggest that the fragility strength parameter is a good indicator of the molecular mobility below Tg, and the heat capacity change at Tgis a good indicator of the configurational entropy. Using these two indicators, 40 structurally diverse pharmaceuticals with known physical stability were analyzed. Four classes of compounds are defined with class I being the most stable and class IV the least stable. The proposed amorphous classification system and methodology for estimating molecular mobility and configurational entropy provides an easily accessible framework to conduct early risk assessments related to physical stability challenges in developing amorphous formulations.

Current non-invasive prenatal screening is targeted toward the detection of chromosomal abnormalities in the fetus1,2. However, screening for many dominant monogenic disorders associated with de novo mutations is not available, despite their relatively high incidence3. Here we report on the development and validation of, and early clinical experience with, a new approach for non-invasive prenatal sequencing for a panel of causative genes for frequent dominant monogenic diseases. Cell-free DNA (cfDNA) extracted from maternal plasma was barcoded, enriched, and then analyzed by next-generation sequencing (NGS) for targeted regions. Low-level fetal variants were identified by a statistical analysis adjusted for NGS read count and fetal fraction. Pathogenic or likely pathogenic variants were confirmed by a secondary amplicon-based test on cfDNA. Clinical tests were performed on 422 pregnancies with or without abnormal ultrasound findings or family history. Follow-up studies on cases with available outcome results confirmed 20 true-positive, 127 true-negative, zero false-positive, and zero-false negative results. The initial clinical study demonstrated that this non-invasive test can provide valuable molecular information for the detection of a wide spectrum of dominant monogenic diseases, complementing current screening for aneuploidies or carrier screening for recessive disorders.

Purpose:To investigate pan-ethnic SMN1 copy-number and sequence variation by hybridization-based target enrichment coupled with massively parallel sequencing or next-generation sequencing (NGS).Methods:NGS reads aligned to SMN1 and SMN2 exon 7 were quantified to determine the total combined copy number of SMN1 and SMN2. The ratio of SMN1 to SMN2 was calculated based on a single-nucleotide difference that distinguishes the two genes. SMN1 copy-number results were compared between the NGS and quantitative polymerase chain reaction and/or multiplex ligation-dependent probe amplification. The NGS data set was also queried for the g.27134T>G single-nucleotide polymorphism (SNP) and other SMN1 sequence pathogenic variants.Results:The sensitivity of the test to detect spinal muscular atrophy (SMA) carriers with one copy of SMN1 was 100% (95% confidence interval (CI): 95.9–100%; n = 90) and specificity was 99.6% (95% CI: 99.4–99.7%; n = 6,648). Detection of the g.27134T>G SNP by NGS was 100% concordant with an restriction fragment-length polymorphism method (n = 493). Ten single-nucleotide variants in SMN1 were detectable by NGS and confirmed by gene-specific amplicon-based sequencing. This comprehensive approach yielded SMA carrier detection rates of 90.3–95.0% in five ethnic groups studied.Conclusion:We have developed a novel, comprehensive SMN1 copy-number and sequence variant analysis method by NGS that demonstrated improved SMA carrier detection rates across the entire population examined.Genet Med advance online publication 19 January 2017

Sexual violence against children remains a global public health problem. The health sector has an opportunity and responsibility to be part of the multisector collaboration to prevent and respond to sexual abuse of minors. The following article presents a critical analysis of hitherto published empirical studies that examine the extent and variety of sexual abuse of minors within the Catholic Church and other institutions. The analysis consists of 40 studies concerning the Catholic Church and 13 studies concerning other institutions not belonging to the Catholic Church. We report the characteristics of the offenders and the offenses. Furthermore, the devastating consequences for children abused by members of powerful institutions are discussed. Knowledge on the role of institutions in sexual abuse of minors and psychological distress following these experiences is necessary to point the way to improvements in prevention and intervention strategies. This literature review is part of a larger research project on the sexual abuse of minors in the context of the Catholic Church in Germany (MHG Study) that is conducted by an interdisciplinary team of psychologists, psychiatrists, criminologists, and sociologists and is funded by the German Bishops’ Conference. Sexuelle Gewalt gegen Kinder bleibt ein globales öffentliches Gesundheitsproblem. Das Gesundheitswesen hat die Gelegenheit und die Verantwortung, ein Teil der sektorübergreifenden Zusammenarbeit zu sein, um sexuellen Missbrauch an Minderjährigen zu verhindern und darauf zu reagieren. Der folgende Beitrag stellt eine kritische Analyse der bisher publizierten empirischen Studien vor, die das Ausmaß und die Art des sexuellen Missbrauchs Minderjähriger innerhalb der katholischen Kirche und anderer Institutionen untersuchen. Die Analyse beinhaltet 40 Studien mit Bezug auf die katholische Kirche und 13 Studien mit Bezug auf andere Institutionen, die nicht zur katholischen Kirche gehören. Wir berichten über die Charakteristika der Täter und die Straftaten. Darüber hinaus werden die verheerenden Folgen für die Kinder, die von Mitgliedern mächtiger Institutionen missbraucht wurden, diskutiert. Das Wissen, welche Rolle Institutionen im sexuellen Missbrauch Minderjähriger spielen und welche seelischen Belastungen solche Erfahrungen nach sich ziehen, ist notwendig, um Wege aufzuzeigen, wie Präventions- und Interventionsstrategien verbessert werden können. Dieser Literaturreview ist Teil eines größeren Forschungsprojekts zum sexuellen Missbrauch an Minderjährigen im Zusammenhang mit der katholischen Kirche in Deutschland (MHG-Studie), das von einem interdisziplinären Team von Psychologen, Psychiatern, Kriminologen und Soziologen durchgeführt und von der Deutschen Bischofskonferenz finanziert wird.

(Abstracted from Nat Med2019;25:439–447)Noninvasive prenatal screening has focused on the detection of chromosomal abnormalities in the fetus. At present, screening for many dominant monogenic disorders associated with de novo mutations is not available, despite their relatively high incidence.

Purpose:Next-generation sequencing (NGS) has been widely applied to clinical diagnosis. Target-gene capture followed by deep sequencing provides unbiased enrichment of the target sequences, which not only accurately detects single-nucleotide variations (SNVs) and small insertion/deletions (indels) but also provides the opportunity for the identification of exonic copy-number variants (CNVs) and large genomic rearrangements.Method:Capture NGS has the ability to easily detect SNVs and small indels. However, genomic changes involving exonic deletions/duplications and chromosomal rearrangements require more careful analysis of captured NGS data. Misaligned raw sequence reads may be more than just bad data. Some mutations that are difficult to detect are filtered by the preset analytical parameters. “Loose” filtering and alignment conditions were used for thorough analysis of the misaligned NGS reads. Additionally, using an in-house algorithm, NGS coverage depth was thoroughly analyzed to detect CNVs.Results:Using real examples, this report underscores the importance of the accessibility to raw sequence data and manual review of suspicious sequence regions to avoid false-negative results in the clinical application of NGS. Assessment of the NGS raw data generated by the use of loose filtering parameters identified several sequence aberrations, including large indels and genomic rearrangements. Furthermore, NGS coverage depth analysis identified homozygous and heterozygous deletions involving single or multiple exons.Conclusion:Our results demonstrate the power of deep NGS in the simultaneous detection of point mutations and intragenic exonic deletion in one comprehensive step.Genet Med 18 5, 513–521.

Next-generation sequencing (NGS) has been widely applied to clinical diagnosis. Target-gene capture followed by deep sequencing provides unbiased enrichment of the target sequences, which not only accurately detects single-nucleotide variations (SNVs) and small insertion/deletions (indels) but also provides the opportunity for the identification of exonic copy-number variants (CNVs) and large genomic rearrangements.

Abstract.Apathy is a diminished goal-directed behavior stemming from a lack of motivation. It is one of the most common symptoms in dementia. While the Apathy Evaluation Scale (AES) has proved to be a psychometrically robust measure for assessing apathy, the German version (AESD) requires further validation. Associations of apathy with important variables in dementia care, such as cognitive impairment or caregiver burden, were repeatedly found, though contradictory findings have also been reported. The present study assessed apathy in 100 community-dwelling persons with dementia. Their informal and formal caregivers used the German informant version of the Apathy Evaluation Scale (AESD-I) to investigate the severity of dementia and cognitive deficits as measured with the Mini-Mental State Examination (MMSE) and Global Deterioration Scale (GDS), respectively. A reliability analysis was performed to estimate the internal consistency of the AESD-I, and the data were tested for potential correlations with results from a shortened version of the AESD-I (AESD16-I). Cronbach’s α was .880 for the AESD-I and .904 for the AESD16-I. The prevalence of apathy was 77%, its severity was on average moderate to high. Significant (p< .05) negative correlations were shown between the AESD16-I, the Barthel Index (BI), and the Quality of Life-Alzheimer’s Disease (QOL-AD). Correlations between the AESD16-I, GDS, and Zarit Burden Interview were positive. After Bonferroni correction, the only correlations that remained significant were between the AESD16-I and BI and QOL-AD. The present study underlines the favorable psychometric properties of the AESD-I and confirms the high prevalence of apathy with considerable severity in the sample of community-dwelling persons with dementia. In addition, it contributes to the diversity of evidence on clinical correlates of apathy which require further clarification.

High-dimensional and time-dependent data pose significant challenges to statistical process monitoring. Dynamic principal-component analysis, recursive principal-component analysis, and moving-window principal-component analysis have been proposed to cope with high-dimensional and time-dependent features. We present a comprehensive review of this literature for the practitioner encountering this topic for the first time. We detail the implementation of the aforementioned methods and direct the reader toward extensions that may be useful to their specific problem. A real-data example is presented to help the reader draw connections between the methods and the behavior they display. Furthermore, we highlight several challenges that remain for research in this area.

Germline mutations in the DNA mismatch repair gene PMS2underlie the cancer susceptibility syndrome, Lynch syndrome. However, accurate molecular testing of PMS2is complicated by a large number of highly homologous sequences. To establish a comprehensive approach for mutation detection of PMS2, we have designed a strategy combining targeted capture next-generation sequencing (NGS), multiplex ligation-dependent probe amplification, and long-range PCR followed by NGS to simultaneously detect point mutations and copy number changes of PMS2. Exonic deletions (E2 to E9, E5 to E9, E8, E10, E14, and E1 to E15), duplications (E11 to E12), and a nonsense mutation, p.S22*, were identified. Traditional multiplex ligation-dependent probe amplification and Sanger sequencing approaches cannot differentiate the origin of the exonic deletions in the 3′ region when PMS2and PMS2CLshare identical sequences as a result of gene conversion. Our approach allows unambiguous identification of mutations in the active gene with a straightforward long-range-PCR/NGS method. Breakpoint analysis of multiple samples revealed that recurrent exon 14 deletions are mediated by homologous Alusequences. Our comprehensive approach provides a reliable tool for accurate molecular analysis of genes containing multiple copies of highly homologous sequences and should improve PMS2molecular analysis for patients with Lynch syndrome.

Intergenerational dialogue is important for personality development in younger and older people, intergenerational solidarity, national and cultural identity, and social change. However, generations differ in approaches to society and history.

Ovarian torsion (OT) in the pediatric patient is an uncommon event and a challenging diagnosis. Clinicians caring for children in the acute setting should be aware of the symptoms and the diagnostic findings of OT. All patients suspected to have OT require consultation with gynecology; however, there is some controversy regarding the best operative intervention. In this article, case discussions will serve as a platform for discussing the epidemiology and clinical manifestations of pediatric OT, as well as reviewing the latest evidence related to the diagnosis and treatment.

Purpose:The mitochondrial genome is highly polymorphic. A unique feature of deleterious mitochondrial DNA (mtDNA) mutations is heteroplasmy. Genetic background and variable penetrance also play roles in the pathogenicity for a mtDNA variant. Clinicians are increasingly interested in requesting mtDNA testing. However, interpretation of uncharacterized mtDNA variants is a great challenge. We suggest a stepwise interpretation procedure for clinical service.Methods:We describe the algorithms used to interpret novel and rare mtDNA variants. mtDNA databases and in silico predictive algorithms are used to evaluate the pathogenic potential of novel and/or rare mtDNA variants.Results:mtDNA variants can be classified into three categories: benign variants, unclassified variants, and deleterious mutations based on database search and in silico prediction. Targeted DNA sequence analysis of matrilineal relatives, heteroplasmy quantification, and functional studies are useful to classify mtDNA variants.Conclusion:Clinical significance of a novel or rare variant is critical in the diagnosis of the disease and counseling of the family. Based on the results from clinical, biochemical, and molecular genetic studies of multiple family members, proper interpretation of mtDNA variants is important for clinical laboratories and for patient care.Genet Med 2012:14(6):620–626

The mitochondrial genome is highly polymorphic. A unique feature of deleterious mitochondrial DNA (mtDNA) mutations is heteroplasmy. Genetic background and variable penetrance also play roles in the pathogenicity for a mtDNA variant. Clinicians are increasingly interested in requesting mtDNA testing. However, interpretation of uncharacterized mtDNA variants is a great challenge. We suggest a stepwise interpretation procedure for clinical service.

The article discusses the belief of the international community that Iran is close to building a nuclear weapon. According to the author, tensions were raised in the last 10 years, with Iran's defiance on its nuclear program of the United Nations. Headed by President Mahmoud Ahmadinejad who claims that the nuclear program of Iran is for generation of energy, Iran has been subjected to a series of economic sanctions including the freezing of Iranian assets in the U.S.

The aim of the study is to support development and effective use of potentials for generativity by implementation and continuous support of local projects funded by German Foundation Remembrance, Responsibility and Futurein Eastern Europe intended to stimulate and increase informal learning in dialogue between generations. Project Evaluation is designed and coordinated by Heidelberg University and contains semi-structured biographical interviews and psychometric scales. Findings suggest that establishing dialogues between generations in the context of local projects is a promising measure to stimulate informal learning, to enhance generativity in older people and to improve perceptions of older people's strengths and potentials in younger generations.

Griseofulvin is a small rigid molecule that shows relatively high molecular mobility and small configurational entropy in the amorphous phase and tends to readily crystallize from both rubbery and glassy states. This work examines the crystallization kinetics and mechanism of amorphous griseofulvin and the quantitative correlation between the rate of crystallization and molecular mobility above and below Tg. Amorphous griseofulvin was prepared by rapidly quenching the melt in liquid N2. The thermodynamics and dynamics of amorphous phase were then characterized using a combination of thermal analysis techniques. After characterization of the amorphous phase, crystallization kinetics above Tgwere monitored by isothermal differential scanning calorimetry (DSC). Transformation curves for crystallization fit a second-order John−Mehl−Avrami (JMA) model. Crystallization kinetics below Tgwere monitored by powder X-ray diffraction and fit to the second-order JMA model. Activation energies for crystallization were markedly different above and below Tgsuggesting a change in mechanism. In both cases molecular mobility appeared to be partially involved in the rate-limiting step for crystallization, but the extent of correlation between the rate of crystallization and molecular mobility was different above and below Tg. A lower extent of correlation below Tgwas observed which does not appear to be explained by the molecular mobility alone and the diminishing activation energy for crystallization suggests a change in the mechanism of crystallization.

Purpose: Mutations in the GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment in populations studied to date. However, the prevalence of mutations varies among different ethnic groups. In most areas of China, genetic testing for nonsyndromic hearing impairment is currently not available because of the lack of information regarding the molecular cause of nonsyndromic hearing impairment. The purpose of this study is to determine the prevalence of a common GJB2 mutation, 235delC, in Chinese deaf children.Methods: We collected DNA specimens from 3004 patients with nonsyndromic hearing impairment from 26 regions of China; 368 Han Chinese and 98 Uigur controls, and screened for the 235delC mutation. The coding exon of the GJB2 gene was polymerase chain reaction amplified, followed by restriction enzyme digestion with ApaI and analysis by agarose gel.Results: Overall, 488 patients (16.3%) were determined to carry at least one 235delC mutant allele, with 233 (7.8%) homozygotes and 255 (8.5%) heterozygotes. Therefore, within the subpopulations examined, the frequency varies from 0% to 14.7% for 235delC homozygotes and from 1.7% to 16.1% for heterozygotes. On the basis of this survey of the patient cohort as stated, Chinese patients with nonsyndromic hearing impairment appear to have a relatively higher 235delC frequency than that of other Asian populations.Conclusion: These results demonstrate that an easy and fast genetic testing method for this well-known GJB2 gene mutation can be made available for at least 2 million Chinese patients and family members with nonsyndromic hearing impairment. By screening for the common GJB2 235delC mutation, the molecular cause in as high as 15% of patients with nonsyndromic hearing impairment in certain regions of China can be identified. In addition, patients who are negative for the 235delC mutation would be candidates for further mutational analysis of GJB2 or other deafness-related genes.

Mutations in GJB2 are associated with hereditary hearing loss. DNA sequencing of GJB2 in a cohort of hearing impaired patients and a multi‐ethnic control group is reported. Among 610 hearing impaired cases, 43 DNA sequence variations were identified in the coding region of GJB2 including 24 mutations, 8 polymorphisms, 3 unclassified variants (G4D, R127C, M163V), 1 controversial variant (V37I), and 7 novel variants (G12C, N14D, V63A, T86M, L132V, D159, 592_600delinsCAGTGTTCATGACATTC). Sixteen non‐coding sequence variations were also identified among cases including the IVS1+1A>G mutation, 2 polymorphisms, and 13 novel variants. A diagnosis of GJB2‐associated hearing loss was confirmed for 63 cases (10.3%). Heterozygous mutations were found in 39 cases (6.4%). Eleven cases carrying novel or unclassified variants (1.8 %) and 18 cases carrying the controversial V37I variant were identified (3%). In addition, 294 control subjects from 4 ethnic groups were sequenced for GJB2. Thirteen sequence variations in the coding region of GJB2 were identified among controls including 2 mutations, 6 polymorphisms, 2 unclassified variants (G4D, T123N), 1 controversial variant (V37I), and 2 novel variants (R127L, V207L). Nine sequence variations were identified among controls in the non‐coding regions in and around GJB2 exon 2. Of particular interest among controls were the variability in carrier rates and ethnic stratification of alleles, and the complex genotypes among Asians, 47% of whom carried two to four sequence variations in the coding region of GJB2. These data provide new information about carrier rates for GJB2‐based hearing loss in various ethnic groups and contribute to evaluation of the pathogenicity of the controversial V37I variant. © 2006 Wiley‐Liss, Inc.

Purpose: We developed a 51-mutation extended cystic fibrosis (CF) panel that incorporates the 25 previously recommended CFTR mutations, plus 26 additional mutations including 3199del6, which was associated with I148T.Methods: This assay utilizes an integrated matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry system.Results: CF testing was performed on over 5,000 individuals, including a 3-year-old Hispanic-American patient with a compound heterozygous G542X/3199del6 genotype. He is negative for I148T, or other mutations assessed by CFTR gene sequencing.Conclusion: These results demonstrate the successful implementation of MALDI-TOF mass spectrometry in CF clinical testing, and establish 3199del6 as a disease-causing CF mutation.

Purpose: We developed a 51-mutation extended cystic fibrosis (CF) panel that incorporates the 25 previously recommended CFTRmutations, plus 26 additional mutations including 3199del6, which was associated with I148T.

Purpose. The aim of this work was to study the assembly, drug loading, and stability of poly(ethylene glycol)-block-poly(∈-caprolactone) (PEG-b-PCL) micelles. Methods. Three PEG-b-PCL compositions with PCL number average molecular weights of 1000, 2500, and 4000 g/mol were used. The assembly of PEG-b-PCL micelles, induced by the addition of water to acetonitrile (ACN), was characterized with 1H nuclear magnetic resonance spectroscopy (1H-NMR) and dynamic light scattering (DLS) with and without the presence of fenofibrate, a poorly water-soluble drug. PEG-b-PCL micelles with encapsulated fenofibrate were prepared through the removal of a negative ACN-water azeotrope under reduced pressure. Fenofibrate content was measured using reverse-phase high-performance liquid chromatography (HPLC), whereas the kinetic stability of PEG-b-PCL micelles with and without encapsulated fenofibrate was evaluated using size exclusion chromatography (SEC). Results. The critical water content (CWC), the water content at which amphiphilic block copolymer (ABC) micelle assembly begins, was determined using DLS and ranged from 10% to 30% water, depending on both PCL molecular weight and PEG-b-PCL concentration. As the water content was increased, the PEG-b-PCL unimers assembled into swollen structures with hydrodynamic diameters ranging from 200 to 800 nm. The 1H-NMR peaks associated with the PCL block exhibited line-broadening, following the addition of D2O, indicating that the PCL blocks reside in the core of the PEG-b-PCL micelle. With further addition of water, the PCL cores collapsed to form fairly monodisperse PEG-b-PCL micelles (20-60 nm). In the presence of fenofibrate, the CWC value was lowered, perhaps due to hydrophobic interactions of fenofibrate and the PCL block. Further addition of water and subsequent evaporation of the negative ACN-water azeotrope resulted in fenofibrate-loaded PEG-b-PCL micelles of under 50 nm. The extent of fenofibrate encapsulation was dependent on PCL block size. At a polymer concentration of 1.0 mg/ml, PEG-b-PCL (5000:4000) and (5000:2500) micelles could encapsulate more than 90% of the initial loading level of fenofibrate, whereas PEG-b-PCL (5000:1000) micelles encapsulate only 28%. SEC experiments revealed that PEG-b-PCL (5000:4000) and (5000:2500) micelles eluted intact, indicating kinetic stability, whereas PEG-b-PCL (5000:1000) micelles eluted primarily as unimers. Conclusions. PEG-b-PCL in ACN assembles with fenofibrate into drug-loaded polymeric micelles with the addition of water and the subsequent removal of a negative ACN-water azeotrope.

Ritonavir is a large, lipophilic molecule that is practically insoluble in aqueous media and exhibits an exceedingly slow intrinsic dissolution rate. Although it has favorable lipophilicity, in vitropermeability studies have shown that ritonavir is a substrate of P-glycoprotein. Thus, the oral absorption of ritonavir could be limited by both dissolution and permeability, thereby making it a Class IV compound in the Biopharmaceutics Classification System. Because formulations rarely exert direct influence on local intestinal permeability, the effect of enhanced dissolution rate on oral absorption was explored. More specifically, poly(ethylene glycol) (PEG)–amorphous ritonavir solid dispersions were prepared with different drug loadings, and the in vitroand in vivoperformances of the dispersions were evaluated. In vitrodissolution was conducted in 0.1NHCl with a USP Apparatus I. A crossover design was used to evaluate the oral bioavailability of amorphous dispersions relative to crystalline drug in beagle dogs. Intrinsic dissolution measurements of the two solid phases indicated a 10-fold improvement in intrinsic dissolution rate for amorphous ritonavir compared with the crystalline counterpart. In vitrodissolution of ritonavir depended on the solid phase as well as drug loading of the dispersion. In vivostudy results indicate that amorphous solid dispersions containing 10–30% drug exhibited significant increases in area under the curve of concentration versus time (AUC) and maximum concentration (Cmax) over crystalline drug. For example, 10% amorphous dispersion exhibited increases of 22- and 13.7-fold in AUC and Cmax, respectively. However, both in vitrodissolution and bioavailability decreased with increasing drug load, which led to the construction of a multiple Level C in vitro–in vivorelationship for this Class IV compound. The established relationship between in vitrodissolution and in vivoabsorption can help guide formulation development. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association

Ritonavir is a large, lipophilic molecule that is practically insoluble in aqueous media and exhibits an exceedingly slow intrinsic dissolution rate. Although it has favorable lipophilicity, in vitro permeability studies have shown that ritonavir is a substrate of P-glycoprotein. Thus, the oral absorption of ritonavir could be limited by both dissolution and permeability, thereby making it a Class IV compound in the Biopharmaceutics Classification System. Because formulations rarely exert direct influence on local intestinal permeability, the effect of enhanced dissolution rate on oral absorption was explored. More specifically, poly(ethylene glycol) (PEG)–amorphous ritonavir solid dispersions were prepared with different drug loadings, and the in vitro and in vivo performances of the dispersions were evaluated. In vitro dissolution was conducted in 0.1N HCl with a USP Apparatus I. A crossover design was used to evaluate the oral bioavailability of amorphous dispersions relative to crystalline drug in beagle dogs. Intrinsic dissolution measurements of the two solid phases indicated a 10-fold improvement in intrinsic dissolution rate for amorphous ritonavir compared with the crystalline counterpart. In vitro dissolution of ritonavir depended on the solid phase as well as drug loading of the dispersion. In vivo study results indicate that amorphous solid dispersions containing 10–30% drug exhibited significant increases in area under the curve of concentration versus time (AUC) and maximum concentration (Cmax) over crystalline drug. For example, 10% amorphous dispersion exhibited increases of 22- and 13.7-fold in AUC and Cmax, respectively. However, both in vitro dissolution and bioavailability decreased with increasing drug load, which led to the construction of a multiple Level C in vitro–in vivo relationship for this Class IV compound. The established relationship between in vitro dissolution and in vivo absorption can help guide formulation development. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:563–570, 2004

The crystallization of amorphous nifedipine was studied using hot-stage microscopy (HSM), powder X-ray diffractometry (PXRD), and differential scanning calorimetry (DSC). The kinetic data obtained from DSC studies under isothermal and nonisothermal conditions were examined using both model-fitting and model-free approaches. Evaluation of 16 different models showed that model A4 (Avrami–Erofeev, n=4) to be most appropriate for crystallization in the conversion range 0.05–0.80. This choice was based on the goodness of fit, the residual plots, and the guidance provided by the model-free approach. The model-free approach indicated that the activation energy decreases slightly as the crystallization proceeds. This variation of the activation energy with the extent of conversion determines the range of conversion over which a model can be fit, and the magnitude of the activation energy helps in the selection of the best model. The model-free approach gives much better predictions than the model of best fit and allows the experimental kinetic function to be numerically evaluated. At the early stage (α=0–0.6), the numerically reconstructed model is almost identical to A4, but gradually approaches A3 (Avrami–Erofeev, n=3) as the crystallization progresses (α=0.6–0.8) and deviates from both models near the end of the reaction. This behavior may be explained by the relative contributions of nucleation and crystal growth at different stages of the reaction. © 2003 Wiley-Liss, Inc. and the American Pharmacists Association.

The crystallization of amorphous nifedipine was studied using hot-stage microscopy (HSM), powder X-ray diffractometry (PXRD), and differential scanning calorimetry (DSC). The kinetic data obtained from DSC studies under isothermal and nonisothermal conditions were examined using both model-fitting and model-free approaches. Evaluation of 16 different models showed that model A4 (Avrami–Erofeev, n = 4) to be most appropriate for crystallization in the conversion range 0.05–0.80. This choice was based on the goodness of fit, the residual plots, and the guidance provided by the model-free approach. The model-free approach indicated that the activation energy decreases slightly as the crystallization proceeds. This variation of the activation energy with the extent of conversion determines the range of conversion over which a model can be fit, and the magnitude of the activation energy helps in the selection of the best model. The model-free approach gives much better predictions than the model of best fit and allows the experimental kinetic function to be numerically evaluated. At the early stage (α = 0–0.6), the numerically reconstructed model is almost identical to A4, but gradually approaches A3 (Avrami–Erofeev, n = 3) as the crystallization progresses (α = 0.6–0.8) and deviates from both models near the end of the reaction. This behavior may be explained by the relative contributions of nucleation and crystal growth at different stages of the reaction. © 2003 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:1779–1792, 2003

The conventional model-fitting approach to kinetic analysis assumes a fixed mechanism throughout the reaction and therefore may be too simplistic for many solid-state reactions. Even for a reaction with a fixed mechanism, model fitting sometimes cannot identify the reaction model uniquely. The alternative model-free approach is sufficiently flexible to allow for a change of mechanism during the course of a reaction and therefore provides a more realistic treatment of solid-state reactions kinetics. The application of model-free analysis to solid-state dehydrations was investigated using the two consecutive dehydration reactions of nedocromil sodium trihydrate. The complexity of such reactions is illustrated by the variation of the activation energy as each dehydration proceeds. The 1st-step dehydration follows one-dimensional phase boundary kinetics until the fraction dehydrated reaches 0.75, and deviates from this model thereafter. The 2nd-step dehydration follows a mechanism intermediate between two- and three-dimensional diffusion that cannot be described by any of the common models. The model-free approach is clearly better than the model-fitting approach for understanding the details of these solid-state dehydration reactions.

The conventional model-fitting approach to kinetic analysis assumes a fixed mechanism throughout the reaction and therefore may be too simplistic for many solid-state reactions. Even for a reaction with a fixed mechanism, model fitting sometimes cannot identify the reaction model uniquely. The alternative model-free approach is sufficiently flexible to allow for a change of mechanism during the course of a reaction and therefore provides a more realistic treatment of solid-state reactions kinetics. The application of model-free analysis to solid-state dehydrations was investigated using the two consecutive dehydration reactions of nedocromil sodium trihydrate. The complexity of such reactions is illustrated by the variation of the activation energy as each dehydration proceeds. The 1st-step dehydration follows one-dimensional phase boundary kinetics until the fraction dehydrated reaches 0.75, and deviates from this model thereafter. The 2nd-step dehydration follows a mechanism intermediate between two- and three-dimensional diffusion that cannot be described by any of the common models. The model-free approach is clearly better than the model-fitting approach for understanding the details of these solid-state dehydration reactions. © 2003 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:1367–1376, 2003

Poly(ethylene glycol) or PEG is an ideal inactive component for preparing simple binary eutectic mixtures because of its low entropy of fusion (~0.0076 J/mol-K), lower melting point (~62°C) compared to most pharmaceuticals, miscibility with drugs at elevated temperatures, and its covalent crystalline lattice. Implication of these physicochemical properties on eutectic crystallization and size reduction of the drug is discussed. Enhancement of the dissolution rate of a poorly soluble compound through the formation of PEG–drug eutectics was investigated using fenofibrate. Solid dispersions of PEG–fenofibrate when characterized, revealed that PEG and fenofibrate form a simple eutectic mixture containing 20–25%(w/w) fenofibrate at the eutectic point. Eutectic crystallization led to the formation of an irregular microstructure in which fenofibrate crystals were found to be less than 10 μm in size. Dissolution rate improvement of fenofibrate correlated with the phase diagram, and the amount of fenofibrate released from the dispersions that contained fenofibrate as a eutectic mixture was at least10-fold higher compared to untreated fenofibrate. On aging, the dissolution rate of the dispersion containing 15%(w/w) fenofibrate in PEG remained unaltered. The results indicate that PEG–drug eutectic formation is a valuable option for particle size reduction and subsequent dissolution rate improvement. © 2003 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 92:505–515, 2003

Poly(ethylene glycol) or PEG is an ideal inactive component for preparing simple binary eutectic mixtures because of its low entropy of fusion (∼0.0076 J/mol‐K), lower melting point (∼62°C) compared to most pharmaceuticals, miscibility with drugs at elevated temperatures, and its covalent crystalline lattice. Implication of these physicochemical properties on eutectic crystallization and size reduction of the drug is discussed. Enhancement of the dissolution rate of a poorly soluble compound through the formation of PEG–drug eutectics was investigated using fenofibrate. Solid dispersions of PEG–fenofibrate when characterized, revealed that PEG and fenofibrate form a simple eutectic mixture containing 20–25%(w/w) fenofibrate at the eutectic point. Eutectic crystallization led to the formation of an irregular microstructure in which fenofibrate crystals were found to be less than 10 μm in size. Dissolution rate improvement of fenofibrate correlated with the phase diagram, and the amount of fenofibrate released from the dispersions that contained fenofibrate as a eutectic mixture was at least10‐fold higher compared to untreated fenofibrate. On aging, the dissolution rate of the dispersion containing 15%(w/w) fenofibrate in PEG remained unaltered. The results indicate that PEG–drug eutectic formation is a valuable option for particle size reduction and subsequent dissolution rate improvement.

This work relates the thermodynamic quantities (Gc, Hc, and Sc) and the molecular mobility values (1/τ) of five structurally diverse amorphous compounds to their crystallization behavior. The model compounds included: ritonavir, ABT‐229, fenofibrate, sucrose, and acetaminophen. Modulated temperature DSC was used to measure the heat capacities as a function of temperature for the amorphous and crystalline phases of each compound. Knowledge of the heat capacities and fusion data allowed calculation of the configurational thermodynamic quantities and the Kauzmann temperatures (TK) using established relationships. The molecular relaxation time constants (τ) were then calculated from the Vogel‐Tammann‐Fulcher representation of the Adam‐Gibbs model. Amorphous samples were heated at 1 K/min and a reduced crystallization temperature, defined as (Tc − Tg)/(Tm−Tg), was used to compare crystallization tendencies. Crystallization was observed for all compounds except ritonavir. The configurational free energy values (Gc) show that thermodynamic driving forces for crystallization follow the order: ritonavir > acetaminophen ≈ fenofibrate > sucrose > ABT‐229. The entropic barrier to crystallization, which is inversely related to the probability that the molecules are in the proper orientation, followed the order: ritonavir > fenofibrate > ABT‐229 > acetaminophen ≈  sucrose. Molecular mobility values, which are proportional to molecular collision rates, followed the order: acetaminophen > fenofibrate > sucrose > ABT‐229 ≈ ritonavir. Crystallization studies under nonisothermal conditions revealed that compounds with the highest entropic barriers and lowest mobilities were most difficult to crystallize, regardless of the thermodynamic driving forces. This investigation demonstrates the importance of both configurational entropy and molecular mobility to understanding the physical stability of amorphous pharmaceuticals. © 2002 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:1863–1872, 2002

This work relates the thermodynamic quantities (Gc, Hc, and Sc) and the molecular mobility values (1/τ) of five structurally diverse amorphous compounds to their crystallization behavior. The model compounds included: ritonavir, ABT-229, fenofibrate, sucrose, and acetaminophen. Modulated temperature DSC was used to measure the heat capacities as a function of temperature for the amorphous and crystalline phases of each compound. Knowledge of the heat capacities and fusion data allowed calculation of the configurational thermodynamic quantities and the Kauzmann temperatures (TK) using established relationships. The molecular relaxation time constants (τ) were then calculated from the Vogel-Tammann-Fulcher representation of the Adam-Gibbs model. Amorphous samples were heated at 1 K/min and a reduced crystallization temperature, defined as (Tc − Tg)/(Tm−Tg), was used to compare crystallization tendencies. Crystallization was observed for all compounds except ritonavir. The configurational free energy values (Gc) show that thermodynamic driving forces for crystallization follow the order: ritonavir > acetaminophen ≈ fenofibrate > sucrose > ABT-229. The entropic barrier to crystallization, which is inversely related to the probability that the molecules are in the proper orientation, followed the order: ritonavir > fenofibrate > ABT-229 > acetaminophen ≈  sucrose. Molecular mobility values, which are proportional to molecular collision rates, followed the order: acetaminophen > fenofibrate > sucrose > ABT-229 ≈ ritonavir. Crystallization studies under nonisothermal conditions revealed that compounds with the highest entropic barriers and lowest mobilities were most difficult to crystallize, regardless of the thermodynamic driving forces. This investigation demonstrates the importance of both configurational entropy and molecular mobility to understanding the physical stability of amorphous pharmaceuticals. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:1863–1872, 2002

This work relates the thermodynamic quantities (Gc, Hc, and Sc) and the molecular mobility values (1/τ) of five structurally diverse amorphous compounds to their crystallization behavior. The model compounds included: ritonavir, ABT-229, fenofibrate, sucrose, and acetaminophen. Modulated temperature DSC was used to measure the heat capacities as a function of temperature for the amorphous and crystalline phases of each compound. Knowledge of the heat capacities and fusion data allowed calculation of the configurational thermodynamic quantities and the Kauzmann temperatures (TK) using established relationships. The molecular relaxation time constants (τ) were then calculated from the Vogel-Tammann-Fulcher representation of the Adam-Gibbs model. Amorphous samples were heated at 1 K/min and a reduced crystallization temperature, defined as (Tc − Tg)/(Tm−Tg), was used to compare crystallization tendencies. Crystallization was observed for all compounds except ritonavir. The configurational free energy values (Gc) show that thermodynamic driving forces for crystallization follow the order: ritonavir > acetaminophen ≈ fenofibrate > sucrose > ABT-229. The entropic barrier to crystallization, which is inversely related to the probability that the molecules are in the proper orientation, followed the order: ritonavir > fenofibrate > ABT-229 > acetaminophen ≈  sucrose. Molecular mobility values, which are proportional to molecular collision rates, followed the order: acetaminophen > fenofibrate > sucrose > ABT-229 ≈ ritonavir. Crystallization studies under nonisothermal conditions revealed that compounds with the highest entropic barriers and lowest mobilities were most difficult to crystallize, regardless of the thermodynamic driving forces. This investigation demonstrates the importance of both configurational entropy and molecular mobility to understanding the physical stability of amorphous pharmaceuticals. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:1863–1872, 2002

Purpose.To define an index based on the van't Hoff equation that can be used as a screening tool for predicting poly(ethylene) glycol (PEG)-drug eutectic composition. Methods.Phase diagrams of PEG with ritonavir, ibuprofen, fenofibrate, naproxen, and griseofulvin were constructed using differential scanning calorimetry, hot stage microscopy and powder X-ray diffractometry. Previously reported phase diagrams were also used to test the predictive capability of the index. Results.This work shows that a modified van't Hoff equation can be used to model the drug liquidus line of these phase diagrams. The slope of the liquidus line depends on the melting point (Tfd) and heat of fusion (ΔHfd) of the drug and describes the initial rate at which the eutectic or monotectic point is approached. Based on this finding, a dimensionless index Icwas defined. The index can be calculated from the melting points of the pure components and heat of fusion of the drug. In addition to the compounds listed above, the index was found to predict the eutectic composition for flurbiprofen, temazepam and indomethacin. These compounds range over 150°C in Tfd, and from 25-65kJ/mole in ΔHfd. Conclusion.Using Icthe approximate eutectic composition for eight different compounds was predicted. The index provides a useful screening tool for assessing the maximum drug loading in a drug-polymer eutectic/monotectic formulation.

A systematic study of the properties of ritonavir and the influence of polyethylene glycol 8000 (PEG) on ritonavir revealed that amorphous ritonavir dispersions in PEG would have an improved dissolution profile and could exhibit long-term stability. Ritonavir, a human immunodeficiency virus (HIV) protease inhibitor, is highly lipophilic [distribution coefficient (log D)= 4.3, 25°C, pH 6.8], poorly water soluble (400 μg/mL in 0.1 N HCl, 1 μg/mL at pH 6.8, 37°C), and exhibits an exceedingly slow dissolution rate (0.03 mg/cm²-min in 0.1 N HCl at 37°C). These properties indicated that a solid dispersion containing ritonavir might be useful for overcoming problems associated with slow dissolution. In addition, ritonavir is a good glass former [glass-transition temperature (Tg)/melting point (Tm) > 0.7]. Amorphous ritonavir has an apparent solubility of 4 mg/mL in 0.1 N HCl at 37°C and shows reasonable stability at 25°C. Amorphous ritonavir, therefore, has properties desirable for preparing a solid dispersion containing this phase. Since PEG, a commonly used polymer, improved the aqueous solubility of crystalline ritonavir, it was expected to have a positive influence on the dissolution rate of ritonavir. Moreover, PEG was found to have negligible plasticizing effect on amorphous ritonavir, which was beneficial for the stability of the dispersion. Finally, solid dispersions of amorphous ritonavir in PEG were prepared, and these dispersions had improved in vitro dissolution rate and were physically stable for > 1.5 years at 25°C when protected from moisture. The performance of this solid dispersion has been attributed to the physicochemical properties of amorphous ritonavir. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:1015–1025, 2001