Perchloric acid (PCA) extracts were prepared from liquid‐N2‐frozen guinea pig brains and their organophosphate profiles examined by P‐31 nuclear magnetic resonance (NMR) spectroscopy. Thirty‐two phosphorus‐containing brain metabolites were characterized and quantitated. A distinctive feature of brain tissue metabolism relative to that of other tissues probed by P‐31 NMR is its pronounced ribose 5‐phosphate content. Comparison of brain metabolite levels following control or sublethal cyanide treatment (4 mg/kg) revealed specific cyanide‐induced changes in brain metabolism. Brains from cyanidetreated animals were characterized by a reduced phosphocreatine content and elevated α‐glycerolphosphate and inorganic orthophosphate contents relative to control. P‐31 NMR spectra of brain PCA extracts at pH 7.2 were also obtained under conditions that approximate those used for in vivo and intact tissue in vitro P‐31 spectroscopic analyses. The spectra reveal nine separate resonance bands corresponding to: sugar phosphates, principally ribose 5‐phosphate (3.7δ); inorganic orthophosphate (2.2δ); glycerol 3‐phosphorylethanolamine (0.3δ); glycerol 3‐phosphorylcholine (−0.1δ); phosphocreatine (−3.2δ); adenosine tri‐(β‐ATP) and di‐(β‐ADP) phosphate ionized end‐groups (−6.2δ); α‐ATP, α‐ADP, and nicotinamide adenine dinucleotides esterified end‐groups (−11.1δ); uridine diphosphohexose, hexose esterified end‐groups (−13.0δ); and β‐ATP ionized middle group (−21.6δ). Knowledge of the phosphatic molecules that contribute resonances to the brain P‐31 NMR spectrum as well as understanding their magnetic resonance properties is essential for the interpretation of in vivo brain spectroscopic data as well as brain extract data, since these same compounds contribute to the intact brain P‐31 spectrum.
very few results on the conformation of amino acids exist,1 234 *which information would lead to a better understanding of the behavior in solution of larger molecules such as peptides and proteins. However, some recent results based on chemical shifts,6 spin-lattice relaxation times of different species,7-9 and couplings of the type (5) D. M. Grant and E. G. Paul, J. Amer. Chem. Soc., 86, 2984.
Of 41 patients with craniofrontonasal syndrome, 35 were female and 6 were male. Although most cases were sporadic, 7 familial instances were found. Craniofrontonasal syndrome represents a unique, incompletely understood X-linked disorder. Unusual manifestations in females included thick, wiry, and curly hair (49%), anterior cranium bifidum (6%), axillary pterygia (9%), unilateral breast hypoplasia (postpubertal; 11%), and asymmetric lower limb shortness (14%).
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