Proton and 31-phosphorus neurospectroscopy in the study of membrane phospholipids and fatty acid intervention in schizophrenia,depression, chronic fatigue syndrome (myalgic encephalomyelitis) and dyslexia

Summary

Neurospectroscopy allows biochemical processes in the brain to be studied non-invasively. At magnetic field strengths of 1.5?T or higher, cerebral proton neurospectroscopy allows the ascertainment of values of myo-inositol, choline-containing compounds, creatine, glutamate, glutamine, and N-acetyl aspartate. At similar field strengths, cerebral 31-phosphorus neurospectroscopy allows the ascertainment of values of phosphomonoesters, inorganic phosphate, phosphodiesters, phosphocreatine, and the gamma, alpha and beta nucleotide triphosphate (mainly adenosine triphosphate) resonances. Since choline is a common polar head group at the Sn3 position of membrane phospholipid molecules, a raised level of free choline, as indexed by proton neurospectroscopy, can indicate relatively low anabolism of membrane phospholipid molecules. Furthermore, the choline peak includes phosphorylcholine and glycerophosphorylcholine and even ethanolamine. The phosphomonoesters peak measured using 31-phosphorus spectroscopy includes major contributions from phosphocholine, phosphoethanolamine and L-phosphoserine, which are important precursors of membrane phospholipids, while the phosphodiesters peak includes contributions from glycerophosphocholine and glycerophosphoethanolamine, which are important products of membrane phospholipid catabolism. Hence proton neurospectroscopy and 31-phosphorus neurospectroscopy can yield important information relating to the metabolism of cerebral membrane phospholipids. The application of these techniques to the investigation of membrane phospholipid metabolism in schizophrenia, depression, chronic fatigue syndrome (myalgic encephalomyelitis or M.E.) and dyslexia is described.     

Short-term (48 hours) versus long-term (7 days) antibiotic prophylaxis for permanent pacemaker implantation

BACKGROUND: Infection following permanent pacemaker implantation is a dreaded complication. Antibiotic prophylaxis for 1-10 days at the time of implant has been used in the past but there is no consensus regarding its duration. We carried out a prospective, randomized study of two durations of antibiotic prophylaxis to determine which one was more effective. METHODS AND RESULTS: One hundred and seventy-eight patients undergoing permanent pacemaker implantation for the first time were randomized to receive short duration (group A, n = 8 8) or longer duration (group B, n = 90) antibiotic prophylaxis for 2 days and 7 days, respectively. Patients in both groups received cloxacillin 2 g 2 hours prior to the procedure followed by ampicillin and cloxacillin (50 mg/kg/day in 4 divided doses) and gentamicin (3 mg/kg/day in 2 divided doses) for the respective duration. Patients were followed up for 1-17.3 months (9.3 +/- 1.8 months) in group A and 1-16.5 months (8.9 +/- 2 months) in group B. One patient in group B had an infection at the pacemaker site and two patients in each group had to undergo reimplantation due to pus in the pocket. There was no significant difference in the primary end-point in both groups. CONCLUSIONS: A short course (48 hours) of antibiotic prophylaxis following permanent pacemaker implantation is as effective as a longer course (7 days).     

基底动脉尖卒中

儿童卒中常见［１］,在过去２０年里,抗磷脂抗体（ＡＰＬＡ）一直被认为是缺血性卒中的一个重要原因。在所有缺血性卒中中,以大脑中动脉分布区最为常见,而后循环则最为罕见［２］．本文报告１例ＡＰＬＡ引起的儿童基底动脉尖卒中。ｌ 病例报告 患儿,男,８岁,因发热４天突发失明１２小时人院．无癫■、神志改变、头痛或呕吐史．无眼痛或幻视,入院时发热。全身周围血管搏动正常,血压正常．其他检查未见明显异常。患儿间歇出现嗜睡,双侧眼睑下垂伴完全失明。上视麻痹伴左视时水平震颤加重。瞳孔３ｍｍ,对光反射正常。眼底正常．躯干…     

Comparative analysis of the large fragment of the 5′ untranslated region (LF-5′ UTR) of serotype A foot-and-mouth disease virus field isolates from India

India is endemic for foot-and-mouth disease (FMD) and in recent years a unique group within serotype A, carrying a codon deletion at an antigenically critical site in capsid protein VP3 has emerged (VP3⁵⁹-deletion group). This tempted us to analyze the noncoding region, which is an under represented area, though critically associated with virus biology and pathogenesis. Analysis of the large fragment of 5′ untranslated region (LF-5′ UTR) of type A FMD virus revealed discrepancy in the overall tree topology between LF-5′ UTR and 1D region possibly due to independent evolution of coding and noncoding regions. The VP3⁵⁹-deletion group maintained its phylogenetic distinctness even at the LF-5′ UTR. Eighteen lineage specific signatures detected here support independent evolutionary paths for the lineages. Extensive deletions of 45 and 89 nucleotides corresponding to the pseudoknot region were noticed. Conservation pattern in the ‘A₂₅₃AACA’ motif in the cre/bus stem-loop indicates the importance of first three ‘A’ residues in VPg uridylylation. Of the three polypyrimidine tract binding protein (PTB) binding sites mapped on the internal ribosome entry site (IRES), the pyrimidine tract (Py tract) in the loop of domain 2 was found to be maximally conserved and it might be the major PTB binding site. Strikingly, a deletion group lineage specific transversion was noticed in the Py tract at the 3′ end of IRES without significantly affecting its in vitro infectious titer. Hence, we presume that for efficient cap-independent viral translation, either a minimum number of pyrimidine residues rather than a complete Py tract or a Py tract tolerating transversions only at specific locations and a core motif ‘CUUU’ within the Py tract is essential.