Hyperosmolarity: effects on nerves and smooth muscle of cutaneous veins

The technique consists in employing successively an extraction method using the dithizone-carbon tetrachloride system, at 4 different pH values, then thin-layer chromatography on silica gel, to identify and separate Ag, Cd, Co, Cu, Hg, Ni, Pb, and Zn in the form of their dithizonates. Sensitivity is of the order of 10(-7) g ion/l. This method is directly applicable in hydrology; after destruction of organic matter in the case of biological samples (blood, urine, excrement). We have applied it in toxicological analysis together with other methods for the detection of copper, lead, mercury and zinc in cases of poisoning.     

Genetic studies of coliphage P1. III. Extended genetic map

An extensive genetic map of coliphage P1 has been constructed for 113 amber mutants, using primarily a modification of the conventional complementation spot test. These spot tests failed to classify the mutants into cistrons, but when they were quantitated they permitted assignment of the mutants into 10 linkage clusters. Furthermore, a linear order could be deduced for most of the mutants within each cluster. This strongly suggested that recombination was the predominant event generating plaques and that, for the practical purpose of rapid genetic mapping, such spot tests could be considered as a series of two-factor crosses. Six of the 10 linkage clusters correlated with the P1 genetic map established by Scott (1968). The locations of the remaining four clusters were determined by three-factor crosses and by prophage deletion mapping. The nonrandom occurrence of termini for 14 deletion prophages, which we established previously (Walker and Walker, 1975), and the coincidence of these termini with five out of ten regions demarcating the linkage clusters are discussed. Complementation tests in liquid frequently gave ambiguous results. Therefore, cistron designations were not assigned.     

The genetics of specific reading disability

Members of the immediate families of twenty children with specific reading disability were examined to determine the prevalence of reading disability within the families. A procedure was developed for identifying adults who may have compensated for a disability manifested more clearly in childhood. Forty-five percent of 75 first-degree relatives of the parents were affected and there was a significantly greater number of affected male relatives than females. No single mode of genetic transmission is evident after inspection of the pedigrees. It is suggested that the disorder is genetically heterogeneous and that subgroups of disabled readers should be looked for.     

Gated blood pool imaging following 99mTc stannous pyrophosphate imaging

Cardiac patients who have undergone 99mTc-stannous pyrophosphate (99mTc-PYP) myocardial imaging can be injected 24 hours later with 99mTc-pertechnetate (99mTc04) to assess left ventricular function. Reduction of 99mTc04 by tin remaining in the blood following the stannous pyrophosphate injection causes labeling of the red cells by 99mTc04 and the creation of a vascular tracer suitable for electrocardiographically gated imaging.     

Posthyperventilation apnea associated with severe hypoxemia

We studied a 14-year-old girl who suffered fractures of her mandible and tegmen following a fall from a balance beam. Thirteen days after hospitalization, she developed severe, protracted, recurrent episodes of hyperventilation; subsequently, she suffered posthyperventilation apnea, which at times was prolonged and association with severe hypoxemia with an arterial oxygen pressure as low as 25 mm Hg. The patient was treated with added dead space and chlorpromazine hydrochloride (Thorazine). Postulated mechanisms for her disorder are discussed. The importance of close clinical and laboratory observation in similar cases is stressed.     

Persistent obstructive jaundice, cholangitis, and biliary cirrhosis due to common bile duct stenosis in chronic pancreatitis

Long strictures of the intrapancreatic portion of the common bile duct were found in 6 patients with chronic pancreatitis. These strictures were responsible for painless obstructive jaundice, recurrent cholangitis, secondary biliary cirrhosis, and chronic abdominal pain difficult to distinguish from that caused by pancreatitis. Endoscopic retrograde cholangiopancreatography and intraoperative cholangiography were invaluable in making the diagnosis and in planning surgical correction. Decompression of the biliary tree by anastomosis of the gallbladder or common duct to the small intestine completely relieved symptoms and allowed liver function to improve significantly. Common duct stricture as a complication of chronic pancreatitis should be considered in the differential diagnosis of extrahepatic biliary obstruction and whenever surgical treatment of chronic pancreatitis is contemplated.     

Metabolism of 2,5-diphenyloxazole (PPO) by trout liver microsomal mixed function monooxygenase

Metabolism of 2,5-diphenyloxazole (PPO) has been characterized in trout liver microsomes. Trout liver microsomes have been found to metabolize PPO into at least one NaOH extractable flourescing metabolite having a strong excitation peak at 345 nm and an emission peak at about 510 nm. As the metabolite(s) has (have) not been characterized, Vmax has not been determined, however in arbitary fluorescent units (FU) Vmax is several fold higher in the trout than in the male rat hepatic microsomes. Km is 12.7 M, being about twice as high as reported for mouse (Cantrell et al. 1975). Optimum assay conditions have been established for the metabolism of PPO by trout liver microsomes. NADPH generating system is essential and the metabolism was strongly inhibited by alpha-naphthoflavone, but much less markedly by SKF 525 A or metyrapone.