Progressive Endergonic Synthesis of Diels-Alder Adducts Driven by Chemical Energy.

The overwhelming majority of artificial chemical reaction networks respond to stimuli by relaxing towards an equilibrium state. The opposite response-moving away from equilibrium-can afford the endergonic synthesis of molecules, of which only rare examples have been reported. Here, we report six examples of Diels-Alder adducts formed in an endergonic process and use this strategy to realize their stepwise accumulation.

ChemFlow_py: a flexible toolkit for docking and rescoring.

The design of accurate virtual screening tools is an open challenge in drug discovery. Several structure-based methods have been developed at different levels of approximation. Among them, molecular docking is an established technique with high efficiency, but typically low accuracy.

RNA origami: design, simulation and application.

Design strategies for DNA and RNA nanostructures have developed along parallel lines for the past 30 years, from small structural motifs derived from biology to large 'origami' structures with thousands to tens of thousands of bases. With the recent publication of numerous RNA origami structures and improved design methods-even permitting co-transcriptional folding of kilobase-sized structures - the RNA nanotechnolgy field is at an inflection point. Here, we review the key achievements which inspired and enabled RNA origami design and draw comparisons with the development and applications of DNA origami structures.

ChemFlow─From 2D Chemical Libraries to Protein-Ligand Binding Free Energies.

The accurate prediction of protein-ligand binding affinities is a fundamental problem for the rational design of new drug entities. Current computational approaches are either too expensive or inaccurate to be effectively used in virtual high-throughput screening campaigns. In addition, the most sophisticated methods, e.

Familial hemiplegic migraine: clinical features and probable linkage to chromosome 1 in an Italian family.

We describe an Italian family with familial hemiplegic migraine (FHM), subtle cerebellar signs and probable linkage to chromosome 1. FHM is genetically heterogeneous; in about 50% of families it is caused by mutations within the CACNA1A gene on chromosome 19. Linkage to 1q31 and 1g21-23 has also been established.

Equine muscular dystrophy with myotonia.

Objectives: To describe a case of equine muscular dystrophy with myotonia.

Methods: A 5-year-old horse presented with hypertrophy and delayed relaxation of the muscles of the hindlimbs from age 2 months. Testicular atrophy developed from 2 years of age.

Sneddon syndrome, arylsulfatase A pseudodeficiency and impairment of cerebral white matter.

We describe a 11 year-old-boy with Sneddon syndrome, confirmed by skin biopsy, and MR evidence of diffuse cerebral hyperintensity of white matter; he also suffered from pre-perinatal hypoxic-ischemic distress. Arylsulfatase A activity was found reduced because of arylsulfatase A pseudodeficiency. We suggest that the association of pre-perinatal distress, Sneddon syndrome and arylsulfatase A pseudodeficiency is responsible for the diffuse impairment of cerebral white matter, never reported in Sneddon syndrome and similar to described cases of delayed posthypoxic demyelination and arylsulfatase A pseudodeficiency.

Cerebellar ataxia, hypogonadism and chorioretinopathy: molecular analysis of an Italian family.

This study aimed to determine if cerebellar ataxia, hypogonadism and chorioretinopathy (AHCR) is associated with mutations in mitochondrial DNA or in genes responsible for spinocerebellar ataxias (SCA1, SCA2, SCA3 and Friedreich's ataxia). Two brothers with cerebellar ataxia, hypogonadism and chorioretinopathy and their unaffected parents underwent molecular analysis for duplications and deletions in mitochondrial DNA (mtDNA), point mutations in the ATP ase 6 gene, and expansions of CAG repeats (at 6p22-p23, 12q24.1, 14q32.

Congenital encephalomyopathy with epilepsy, chorioretinitis, basal ganglia involvement, and muscle minicores.

A woman had severe psychomotor retardation, epilepsy, rigidity, and chorioretinitis. Magnetic resonance imaging showed cerebellar and cerebral atrophy and hypointensities in T2-weighted images of the thalami and basal ganglia. Muscle biopsy documented size variations in rounded muscle fibers, fibrosis, and minicores on electron microscopy.

Leber's Hereditary Optic Neuropathy (LHON) with 14484/ND6 mutation in a North African patient.

We report the clinical and genetic study of a Leber's Hereditary Optic Neuropathy (LHON) patient of North African origin harboring the 14484/ND6 mutation of mtDNA. For over a year we followed the ophthalmological course of this 24-year-old male with LHON treated with idebenone and vitamin B12. Serum lactate after effort was evaluated before, during and after therapy.

Molecular pathology of fatal familial insomnia.

Fatal familial insomnia (FFI) is linked to a mutation at codon 178 of the prion protein gene, coupled with the methionine codon at position 129, the site of a methionine/valine polymorphism. The D178N mutation coupled with the 129 valine codon is linked to a subtype of Creutzfeldt-Jakob disease (CJD178) with a different phenotype. Two protease resistant fragments of the pathogenic PrP (PrPres), which differ in molecular mass, are associated with FFI and CJD178, respectively, suggesting that the two PrPres have different conformations and hence they produce different disease phenotypes.

Searching for migraine genes: exclusion of 290 cM out of the whole human genome.

A linkage and association analysis was made on 14 Italian families with recurrent migraine. We analyzed five chromosomal regions surrounding the candidate genes 5HT1D (1p36.3-34.

Defective brain and muscle energy metabolism shown by in vivo 31P magnetic resonance spectroscopy in nonaffected carriers of 11778 mtDNA mutation.

In vivo phosphorus magnetic resonance spectroscopy (31P-MRS) showed defective brain and muscle energy metabolism in three affected siblings in a family with Leber's hereditary optic neuropathy (LHON) with the 11778 mtDNA mutation. We studied 14 nonaffected members of the same pedigree by 31P-MRS and molecular genetics. Nine of 14 individuals studied had the 11778 mtDNA mutation, with various degrees of heteroplasmy.

Familial progressive subcortical gliosis: presence of prions and linkage to chromosome 17.

Progressive subcortical gliosis (PSG) is a sporadic and familial dementing disease characterized pathologically by astrogliosis at the cortex-white matter junction, a feature present in some prion diseases. With immunocytochemical and Western blot analyses, we investigated the presence of deposits of the prion protein (PrP) and of the protease-resistant PrP isoform, the hallmarks of prion diseases, in six affected members of two large kindreds with PSG. The coding region of the PrP gene was sequenced and chromosomal linkage determined.

31P-magnetic resonance spectroscopy in migraine without aura.

We investigated 22 patients with migraine without aura, all drug-free and in headache-free periods, by means of 31P-magnetic resonance spectroscopy (MRS) of brain and muscle. Brain 31P-MRS showed significantly low phosphocreatine, increased adenosine diphosphate, and decreased phosphorylation potential. There was a slow rate of phosphocreatine recovery after exercise in the muscle of 12 of 22 patients.

A novel mechanism of phenotypic heterogeneity demonstrated by the effect of a polymorphism on a pathogenic mutation in the PRNP (prion protein gene).

Fatal familial insomnia (FFI) is a subacute dementing illness originally described in 1986. The phenotypic characteristics of this disease include progressive untreatable insomnia, dysautonomia, endocrine and motor disorders, preferential hypometabolism in the thalamus as determined by PET scanning, and selective thalamic atrophy. These characteristics readily distinguish FFI from other previously described neurodegenerative conditions.

Fatal familial insomnia and familial Creutzfeldt-Jakob disease: different prion proteins determined by a DNA polymorphism.

Fatal familial insomnia and a subtype of Creutzfeldt-Jakob disease, two clinically and pathologically distinct diseases, are linked to the same mutation at codon 178 (Asp-178-->Asn) but segregate with different genotypes determined by this mutation and the methionine-valine polymorphism at codon 129 of the prion protein gene. The abnormal isoforms of the prion protein in these two diseases were found to differ both in the relative abundance of glycosylated forms and in the size of the protease-resistant fragments. The size difference was consistent with a different protease cleavage site, suggesting a different conformation of the protease-resistant prion protein present in the two diseases.

Arylsulfatase A pseudodeficiency and Lafora bodies in a patient with progressive myoclonic epilepsy.

Since age 12 years, a 25-year-old woman had a syndrome with myoclonic epilepsy, cerebellar signs, and spontaneous myoclonus. Skin biopsy showed typical Lafora bodies (LB), but she lacked a progressive course and mental impairment, hallmarks of Lafora disease. Lysosomal enzyme assays showed low level arylsulfatase A (ASA) activity.

Abnormal platelet mitochondrial function in patients affected by migraine with and without aura.

To investigate energy metabolism in migraine, we determined platelet mitochondrial enzyme activities in 40 patients with migraine with aura and in 40 patients with migraine without aura during attack-free intervals and in 24 healthy control subjects. NADH-dehydrogenase, citrate synthase and cytochrome-c-oxidase activities in both patient groups were significantly lower than in controls (p < 0.01), while NADH-cytochrome-c-reductase activity was reduced only in migraine with aura (p < 0.

Testing models for genetic determination in migraine.

We collected two clinically matched samples of patients, one sample affected by migraine with aura the other by migraine without aura, to investigate the genetic determination of these conditions. A maternal and X-linked transmission for both these diseases was considered unlikely after pedigree analysis. Classical segregation analysis indicated a likely autosomal recessive kind of transmission for both.

Abnormal brain and muscle energy metabolism shown by 31P magnetic resonance spectroscopy in patients affected by migraine with aura.

We studied brain and muscle energy metabolism by phosphorus 31 magnetic resonance spectroscopy (31P-MRS) in 12 patients affected by migraine with aura (classic migraine) in interictal periods. Brain 31P-MRS disclosed a low phosphocreatine content in all patients, accompanied by high adenosine diphosphate concentration, a high percentage of V/Vmax (adenosine triphosphate), and a low phosphorylation potential--features showing an unstable state of metabolism in classic migraine. Abnormal muscle mitochondrial function, in the absence of clinical signs of muscle impairment, was present in nine of the 12 patients examined.

Abnormal sympathetic skin responses in thalamic lesions.

Sympathetic skin responses (SSRs) were abolished in 4 patients affected with fatal familial thalamic degeneration involving the anterior (A) and dorsomedial (DM) thalamic nuclei, without lesions of the peripheral vegetative system. Abnormalities of SSR were not due to peripheral nerve lesions. It is concluded that SSR integrity also depends upon thalamic formations ("visceral" thalamus) and their frontal cortical connections.