Estimation of lecithin in rabbit tissues

1. A simple method for lecithin estimation was developed. Phospholipids in rabbit tissues were extracted with chloroform and methanol. 2. The samples were chromatographed with eluting solvent system; chloroform:methanol:glacial acetic acid:water (100:25:8:1.1). Lecithin was identified by the spray reagent as blue spots and the intensities were quantitated with a densitometer. 3. The concentration of lecithin in the various rabbit tissues varied from 2.8 to 10 mg/g tissue. The sequence of increasing lecithin concentration was heart less than kidney less than lung less than liver less than brain. 4. Recovery experiments of added lecithin into the tissues showed a recovery of 91-104%.

Phenytoin and phenobarbitone plasma level-dose relationships in Chinese epileptic children in Singapore

In a study of 30 Chinese epileptic children, 43% had poor seizure control. The average daily dose of phenytoin was 6.1 +/- 0.53 mg/kg, and the mean plasma level was 4.2 +/- 0.63 microgram/ml, as determined by the enzyme immunoassay (EMIT) method. The phenytoin plasma level (microgram/ml) versus daily dose (mg/kg) ratios in 73% of these patients were below 1. The average daily dose of phenobarbitone was 5.1 +/- 0.36 mg/kg, and the mean plasma level was 24.8 +/- 1.7 microgram/ml -- also estimated by EMIT. Only one patient showed adverse effects. Poor seizure control in patients was chiefly due to subtherapeutic concentrations of phenytoin, which cannot be attributed to poor patient compliance. The presence of phenobarbitone might have accelerated phenytoin metabolism, or the drug could have been lost through sweating. The pharmacokinetics of phenytoin in these Chinese children may be genetically different and might have caused the subtherapeutic phenytoin levels.

Synovial biopsy by Franklin--Silverman needle

Franklin-Silverman needles, commonly used for liver biopsies, were used for biopsy of synovia of 75 joints. The results indicate a higher percentage of success in obtaining pathologic specimens than with previously reported instruments. Complications were rare, with only milk transient hemarthrosis being found in 5 cases. For an accurate diagnosis, multiple specimens should be obtained since single specimens are too small to interpret histopathologically. Being simpler and safer, the Franklin-Silverman needle biopsy is recommended as a routine procedure for early diagnosis of synovial diseases of the joint in conjunction with joint aspiration. The success rate depends not only on the type of needle used but also on the proper selection of the biopsy site.

Cardiovascular effects of benzquinamide

The cardiovascular effects of benzquinamide were evaluated in anesthetized dogs. Intravenous benzquinamide, 0.5 to 5 mg/kg, caused tachycardia, elevated blood norepinephrine levels, frequent ventricular arrhythmias, and brief hypotension. Ganglionic blockade by hexamethonium prior to administration of benzquinamide prevented the tachycardia and alterations in norepinephrine levels but prolonged the period of hypotension. In isolated mesenteric arterial preparations benzquinamide interfered with contractile force generated by potassium chloride, norepinephrine, and prostaglandin F2 alpha. It is concluded that benzquinamide directly relaxes vascular smooth muscle thereby producing in vivo reduced peripheral vascular resistance and hypotension, which are compensated for by reflex sympathetic activation.

Patients' comments on psychiatric inpatient treatment experiences: patient-therapist relationships and their implications for treatment outcome

Only few researchers pay systematic attention to what patients may have to say about their treatment experience during psychiatric hospitalization. This study not only delineates the various therapeutic aspects of an open psychiatric inpatient unit based on the patients' comments, but also attempts to correlate the data with the objective outcome of treatment rated clinically by the therapists and independently by the author. Positive patient-therapist relationship has been found to be the most significant factor correlated closely with the treatment outcome. The correlation may support the relevance of the patients' comments regarding subjectively perceived therapeutic benefits vs. objective actual benefits.

Effect of reductive alkylation of the epsilon-amino group of lysyl redsidues of casein on its nutritive value in rats

Casein epsilon-aminolysyl residues were converted to the methyl (and dimethyl), isopropyl or cyclopentyl derivatives in high yield with formaldehyde, acetone or cyclopentanone, respectively, in the presence of sodium borohydride. When incorporated into diets at 10% as the sole protein source, the chemically modified caseins failed to support growth of young rats. Methyl casein did, however, support limited growth after about 5 days. Plasma threonine levels increased and lysine levels decreased markedly in rats fed the alkyl caseins. The respective alkyllsine derivatives were present in plasma and urine. In another experiment, nearly normal or normal growth was obtained by feeding lysine-supplemented methyl or isopropyl casein, respectively. A preparation of partially methylated casein, containing approximately equal amounts of monomethyl- and dimethyllysines, supported normal rat growth. These results demonstrate that lysine deficiency was produced by feeding highly alkylated caseins. Digestibility of the chemically modified caseins in vivo was not affected, although in vitro studies with trypsin and alpha-chymotrypsin showed lowered digestibility. Since no apparent toxicity was observed limited methylation of food proteins may be useful for protection of lysyl residues against deteriorative reactions during processing and storage.

Synthesis of immobilized flavin derivatives and their use in purification of chicken egg-white ovoflavoprotein

Affinity adsorbents for flavoproteins were prepared by the covalent attachment of polyacrylamide and agarose to flavin derivatives linked through position N(3) of the flavin nucleus. 3-Carboxymethyl-FMN covalently linked to aminoalkyl substituted agarose was successfully used for the separation and purification of the apo form of the ovoflavoprotein from chicken egg white. High yields and high purities were achieved by two different isolation procedures employing the affinity adsorbent.