RESUMO
The structural motif within a series of tetrahydropyrimidine-based isothioureas necessary for generating high asymmetric induction in the asymmetric Steglich rearrangement of oxazolyl carbonates is fully explored, with crossover and dynamic (19)Fâ NMR experiments used to develop a mechanistic understanding of this transformation.
Assuntos
Carbonatos/química , Bases de Lewis/química , Oxazóis/química , Pirimidinas/química , Tioureia/química , Catálise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , EstereoisomerismoRESUMO
Duchenne muscular dystrophy (DMD) is a dystrophin-deficient lethal muscle disease. To date, the catastrophic muscle wasting phenotype has only been seen in dystrophin-deficient humans and dogs. Although Duchenne-like symptoms have been observed in more than a dozen dog breeds, the mutation is often not known and research colonies are rarely established. Here, we report an independent canine DMD model originally derived from the Pembroke Welsh corgi breed. The affected dogs presented clinical signs of muscular dystrophy. Immunostaining revealed the absence of dystrophin and upregulation of utrophin. Histopathologic examination showed variable fiber size, central nucleation, calcification, fibrosis, neutrophil and macrophage infiltration and cardiac focal vacuolar degeneration. Carrier dogs also displayed mild myopathy. The mutation was identified as a long interspersed repetitive element-1 (LINE-1) insertion in intron 13, which introduced a new exon containing an in-frame stop codon. Similar mutations have been seen in human patients. A colony was generated by crossing carrier females with normal males. Affected puppies had a normal birth weight but they experienced a striking growth delay in the first 5 days. In summary, the new corgi DMD model offers an excellent opportunity to study DMD pathogenesis and to develop novel therapies.
Assuntos
Modelos Animais de Doenças , Cães , Distrofina/genética , Mutação INDEL/genética , Íntrons/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Distrofia Muscular de Duchenne/genética , Análise de Variância , Animais , Western Blotting , Creatina Quinase/sangue , Primers do DNA/genética , Imunofluorescência , Genótipo , Técnicas Histológicas , Imuno-Histoquímica , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/patologia , Utrofina/metabolismoRESUMO
Screening of a range of chiral isothioureas and acyl donors to promote the asymmetric C-acylation of silyl ketene acetals indicates that C(2)-aryl-dihydropyrimidobenzothiazole-derived isothioureas and propionic anhydride give optimal reactivity and enantioselectivity in this process. Under optimised conditions 3-acyl-3-aryl or 3-acyl-3-alkylfuranones are prepared in good yields and moderate to excellent enantioselectivities (up to 98% ee; ee=enantiomeric excess).
Assuntos
Acetais/química , Etilenos/química , Cetonas/química , Silanos/química , Tioureia/química , Acilação , Catálise , Furanos/síntese química , Furanos/química , EstereoisomerismoRESUMO
The catalytic activity and enantioselectivity in the kinetic resolution of (±)-1-naphthylethanol with a range of structurally related 3,4-dihydropyrimido[2,1-b]benzothiazole-based catalysts is examined. Of the isothiourea catalysts screened, (2S,3R)-2-phenyl-3-isopropyl substitution proved optimal, giving good levels of selectivity in the kinetic resolution of a number of secondary alcohols (S values up to >100 at ~50% conversion). Low catalyst loadings (0.10-0.25 mol%) of the optimal isothiourea can be used to generate enantiopure alcohols (>99% ee) in good yields.
Assuntos
Benzotiazóis/química , Tioureia/química , Acilação , Aminas/química , Catálise , Estrutura Molecular , EstereoisomerismoRESUMO
Patients affected by pseudohypoparathyroidism (PHP) or related disorders are characterized by physical findings that may include brachydactyly, a short stature, a stocky build, early-onset obesity, ectopic ossifications, and neurodevelopmental deficits, as well as hormonal resistance most prominently to parathyroid hormone (PTH). In addition to these alterations, patients may develop other hormonal resistances, leading to overt or subclinical hypothyroidism, hypogonadism and growth hormone (GH) deficiency, impaired growth without measurable evidence for hormonal abnormalities, type 2 diabetes, and skeletal issues with potentially severe limitation of mobility. PHP and related disorders are primarily clinical diagnoses. Given the variability of the clinical, radiological, and biochemical presentation, establishment of the molecular diagnosis is of critical importance for patients. It facilitates management, including prevention of complications, screening and treatment of endocrine deficits, supportive measures, and appropriate genetic counselling. Based on the first international consensus statement for these disorders, this article provides an updated and ready-to-use tool to help physicians and patients outlining relevant interventions and their timing. A life-long coordinated and multidisciplinary approach is recommended, starting as far as possible in early infancy and continuing throughout adulthood with an appropriate and timely transition from pediatric to adult care.
Assuntos
Diabetes Mellitus Tipo 2 , Nanismo Hipofisário , Hipotireoidismo , Pseudo-Hipoparatireoidismo , Transição para Assistência do Adulto , Adulto , Criança , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Nanismo Hipofisário/diagnóstico , Nanismo Hipofisário/terapia , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/terapia , Guias de Prática Clínica como Assunto , Pseudo-Hipoparatireoidismo/diagnóstico , Pseudo-Hipoparatireoidismo/terapiaRESUMO
The ketogenic diet (KD) is a nonpharmacologic treatment to reduce seizures with moderate to high success in pediatric patients with intractable epilepsy. Initiated in hospital, parents continue the treatment at home ensuring the ratio of high fat to low carbohydrate/protein is maintained to achieve metabolic ketosis. We conducted a systematic review to examine the quality of life (QoL) for families with a child using the KD for the reduction in epileptic seizures. A systematic review of the literature was conducted from 2007-2014 using key terms and combinations of: "epilepsy," "ketogenic diet," "children," "family," and "quality of life." We accessed CINAHL, Medline, PubMed, and PsycINFO. After removing duplicates, we screened 598 papers by title and abstract. Articles comparing alternate diets such as the Atkins diet to the KD, or those focusing on the KD and societal costs, were excluded. Eighteen articles remained, including 7 intervention studies (randomized controlled trial and quasiexperimental), 7 descriptive studies (retrospective), 2 observational studies, and 2 case studies. Most participants were diagnosed with epilepsy at the age of 5 y, and had a trial of antiepileptic drugs (AEDs) and had been using the KD after discharge from the hospital. QoL was infrequently reported as a primary variable and was defined in a variety of ways. We found recurring themes that could affect QoL: efficacy of seizure reduction, nutritional status, child growth and development, and child and family psychosocial impact. The dominant psychological factor was the need for counseling for parents and clear expectations on expected outcomes. Nonadherence and dropout rates were frequent, but unfortunately the reasons and timing were not well documented, and some of these could be associated with QoL. The success of the KD in seizure reduction addressed a primary parental concern. Further research should address KD adherence and dropout rates, and investigate factors of quality of life.
RESUMO
This Consensus Statement covers recommendations for the diagnosis and management of patients with pseudohypoparathyroidism (PHP) and related disorders, which comprise metabolic disorders characterized by physical findings that variably include short bones, short stature, a stocky build, early-onset obesity and ectopic ossifications, as well as endocrine defects that often include resistance to parathyroid hormone (PTH) and TSH. The presentation and severity of PHP and its related disorders vary between affected individuals with considerable clinical and molecular overlap between the different types. A specific diagnosis is often delayed owing to lack of recognition of the syndrome and associated features. The participants in this Consensus Statement agreed that the diagnosis of PHP should be based on major criteria, including resistance to PTH, ectopic ossifications, brachydactyly and early-onset obesity. The clinical and laboratory diagnosis should be confirmed by a molecular genetic analysis. Patients should be screened at diagnosis and during follow-up for specific features, such as PTH resistance, TSH resistance, growth hormone deficiency, hypogonadism, skeletal deformities, oral health, weight gain, glucose intolerance or type 2 diabetes mellitus, and hypertension, as well as subcutaneous and/or deeper ectopic ossifications and neurocognitive impairment. Overall, a coordinated and multidisciplinary approach from infancy through adulthood, including a transition programme, should help us to improve the care of patients affected by these disorders.
Assuntos
Diagnóstico Tardio/efeitos adversos , Hormônio Paratireóideo/uso terapêutico , Guias de Prática Clínica como Assunto , Pseudo-Hipoparatireoidismo/diagnóstico , Pseudo-Hipoparatireoidismo/terapia , Consenso , Resistência a Medicamentos , Feminino , Predisposição Genética para Doença , Humanos , Recém-Nascido , Masculino , Triagem Neonatal/organização & administração , Prognóstico , Desenvolvimento de Programas , Pseudo-Hipoparatireoidismo/genética , Medição de RiscoRESUMO
Isothiourea DHPB promotes the diastereoselective C-acylation of silyl ketene acetals with anhydrides or benzoyl fluoride, giving 3-acyl-3-aryl or 3-acyl-3-alkylfuranones in excellent yields and stereoselectivities (up to 99:1 dr).