Congenital stenosis of the pulmonic and tricuspid valves. Clinical, hemodynamic and angiographic observations in a 20 year old woman

Patients with congenital stenosis of the tricuspid and pulmonic valves are rare, indeed, and are expected to have underdeveloped right ventricles. The three obstructions in series, namely, tricuspid orifice, right ventricular inflow and right ventricular outflow typically result in symptomatic, cyanotic infants or young children with right to left shunts at atrial level. We present unique clinical, hemodynamic and angiographic information on a 20 year old acynotic, virtually asymptomatic woman with normally formed right ventricle and congenital stenosis of the tricuspid and pulmonic valves.     

Approach to seizures in the neonatal period: a European perspective

In the neonatal period, seizures rank among the most common neurological symptoms, often indicating an underlying serious neurological condition. It is remarkable that although new tools have been incorporated into the diagnosis of neonatal seizures, there is no consensus about the therapeutic approach among different doctors and institutions. Hence, although phenobarbital is still considered the initial drug of choice, the protocols reported in the literature show a great variability in the approach to treatment of refractory seizures. We used a questionnaire to gain information regarding the treatment of seizures in the neonatal period in different European institutions. Conclusion: We conclude that phenobarbital is still the initial drug of choice followed by benzodiazepines, except in preterm infants with a birth weight below 1800 g. In refractory seizures, the use of continuous lidocaine infusion is most common. Of note, clinical studies with newer drugs have been mostly performed in the United States but not in Europe.     

Erythropoietin structure-function relationships: high degree of sequence homology among mammals

To investigate structure-function relationships of erythropoietin (Epo), we have obtained cDNA sequences that encode the mature Epo protein of a variety of mammals. A first set of primers, corresponding to conserved nucleotide sequences between mouse and human DNAs, allowed us to amplify by polymerase chain reaction (PCR) intron 1/exon 2 fragments from genomic DNA of the hamster, cat, lion, dog, horse, sheep, dolphin, and pig. Sequencing of these fragments permitted the design of a second generation of species-specific primers. RNA was prepared from anemic kidneys and reverse-transcribed. Using our battery of species-specific 5' primers, we were able to successfully PCR- amplify Epo cDNA from Rhesus monkey, rat, sheep, dog, cat, and pig. Deduced amino acid sequences of mature Epo proteins from these animals, in combination with known sequences for human, Cynomolgus monkey, and mouse, showed a high degree of homology, which explains the biologic and immunological cross-reactivity that has been observed in a number of species. Human Epo is 91% identical to monkey Epo, 85% to cat and dog Epo, and 80% to 82% to pig, sheep, mouse, and rat Epos. There was full conservation of (1) the disulfide bridge linking the NH2 and COOH termini; (2) N-glycosylation sites; and (3) predicted amphipathic alpha- helices. In contrast, the short disulfide bridge (C29/C33 in humans) is not invariant. Cys33 was replaced by a Pro in rodents. Most of the amino acid replacements were conservative. The C-terminal part of the loop between the C and D helices showed the most variation, with several amino acid substitutions, deletions, and/or insertions. Calculations of maximum parsimony for intron 1/exon 2 sequences as well as coding sequences enabled the construction of cladograms that are in good agreement with known phylogenetic relationships.     

鼓槌石斛中一新的联苄类化合物——鼓槌石斛素

从兰科鼓槌石斛(Dendrobium chrysotoxum)中分得一新的联苄类化合物,经光谱分析(UV,IR,MS,¹HNMR,¹³CNMR和DIFNOE),其结构确定为4-羟基-3,5,3',4'-四甲氧基联苄,命名为鼓槌石斛素。关键词鼓槌石斛;鼓槌石斛素;联苄类化合物。