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The effects of acute withdrawal from cigarette smoking on indocyanine green (ICG) clearance and antipyrine pharmacokinetics were studied in healthy young male volunteers. Two separate crossover clinical trials, each using 12 subjects, were used to compare the disposition of the drugs from 24 to 36 hours after withdrawal to the disposition found under control conditions. The median difference of ICG clearance and all antipyrine pharmacokinetic parameters from smoking control was less than 13%, indicating that short-term smoking withdrawal had no effect large enough to be of clinical significance on hepatic blood flow or hepatic drug-metabolizing capacity. Rates of hepatic blood flow were normal in comparison with values published for larger sample populations. The lack of any clinically significant effect of smoking withdrawal on hepatic blood flow or on the disposition of antipyrine, a drug with very low hepatic extraction, indicates that on a pharmacokinetic basis, changes in dosage regimens for most drugs are not necessary on acute withdrawal from smoking. [ABSTRACT FROM AUTHOR]

The intravenous disposition of theophylline was determined in 12 healthy young male smokers during periods of smoking and short-term withdrawal (24 to 36 hours), using a crossover design. Median half-life, clearance, volume of distribution, hepatic extraction, and intrinsic clearance of theophylline during withdrawal were within ±5% of the corresponding median control (smoking) parameters and were normal in comparison with values published for smokers. The lack of change in the pharmacokinetic profile of theophylline indicates that adjustment of the dosage regimen should not be necessary immediately after smoking withdrawal. [ABSTRACT FROM AUTHOR]

This paper develops an agent-based model to quantify the impact of COVID-19 on household debt and savings. To build a representative cross-section of households that vary by income, debt portfolios and consumption baskets, we merge data from the Survey of Household Spending and the Survey of Financial Security. We construct paths for consumption and employment over the crisis, accounting for heterogeneous risk of unemployment across demographics, government transfers, and substitution between expenditure categories that vary in contact intensity. Our model simulations yield a heterogeneous effect of COVID-19 across the income distribution. Low-income households face the highest risk of unemployment, but transfers provide generous income replacement. Middle-income job losers see the fastest rise in debt because transfers only partially replace lost income. Most unplanned savings are accumulated by high-income households that face lower risk of unemployment and larger declines in hard-to-distance spending. We find the rise in savings could generate a brief jump of nearly 6% of monthly consumption., (© 2022 Canadian Economics Association.)

Sphingolipid fatty acids are first converted to a mixture of free acids and their n-butyl esters by heating the specimen at 85 degree C in aqueous butanolic hydrogen chloride; the butyl esters are then saponified with methanolic potassium hydroxide. After acidification and extraction into hexane, the fatty acids are extracted into a very small volume of aqueous trimethyl(m-trifluorotolyl)ammonium hydroxide (TMTFTH), injection of an aliquot of the TMTFTH extract into the gas chromatograph yields the fatty acid methyl esters by pyrolytic methylation of the quaternary ammonium salts of the fatty acids. The preparation of a specimen ready for the gas--liquid chromatographic (GLC) analysis with quantitative recovery of the sphingolipid fatty acids can be accomplished in less than 2 h. By comparison, none of a number of well-accepted techniques for the release of sphingomyelin fatty acids by hydrolysis or methanolysis released the fatty acids quantitatively in less than 3 h, and all required additional manipulations before GLC analysis.

Clinical, light microscopical, ultrastructural, and biochemical studies were done on nerve and muscle biopsy specimens from five patients with the oculo-cerebral-renal syndrome of Lowe. Four patients were American Indians, a racial group in whom this disease has not previously been recognized. The hypotonia, areflexia, and diffuse atrophy of muscles are associated with slowed motor nerve conduction velocities, and the morphologic changes in sensory nerves are attributed to a "dying-back" phenomenon probably resulting from an unknown metabolic derangement.

The total saponifiable fatty acids of three stable L-phase variants of Staphylococcus aureus induced by cycloserine, methicillin, and lysostaphin were examined by gas-liquid chromatography. Five separate preparations of each of the three variants were examined. Twenty-nine fatty acids were identified. The fatty acid patterns of the three variants were very similary.

Adult male rats were starved by allowing them one fifth of their measured daily food consumption until they lost 40% of their initial body weights. Some of these rats were then refed until their initial body weights were reached. We measured the total content of the following in the lung tissue of fed, starved, and refed animals: (1) elastin, (2) hydroxyproline, and (3) protein. Body weight and lung dry and wet weights were significantly reduced in starved and similar in refed rats compared with fed animals. Total contents of crude connective tissue, hydroxyproline, elastin, and protein were significantly lower in starved than in fed rat lungs. After refeeding, hydroxyproline content returned completely to levels found in fed rats, but other components only partially returned to normal values. These results provide a biochemical counterpart for our previous observations on the effects of starvation and refeeding on lung mechanics and morphologic aspects. It appears that the emphysema like changes in the lungs of starved rats are at least partly related to the loss of connective tissue elements.

Forty-four cases of lipogranulomas (LG) in non-fatty livers (NFL), consisting of 38 biopsies and six autopsy livers, were studied. LG in NFL have a distinct morphologic characteristic and virtually all are attached to or closely associated with the walls of hepatic venules. The reason for this peculiar location remains unexplained. Our data from lipid histochemistry and analysis of lipid extracts from the livers and foodstuffs by thinlayer chromatography and gas-liquid chromatography indicate that LG in NFL most likely represent a reaction to absorbed saturated hydrocarbons, like mineral oil, used widely in the food industry. The incidence of LG is increasing, as evidenced by a 1.7% incidence in 1952-53 compared with 4.6% in 1978-80. LG seldom present a diagnostic problem provided serial sections are examined. An awareness of the characteristic morphology will prevent an extensive granuloma work-up. They appear to be an incidental finding in liver biopsies, and of no clinical significance at present; however, their long-term implication, if any, must await future observations.

A gas-liquid chromatographic micromethod for quantitation of cholesterol in 20 micro l of plasma was developed using 5alpha-cholestane as an internal standard, saponification with tetramethylammonium hydroxide-isopropanol, and extraction with tetrachloroethylene-methyl butyrate. Cholesterol levels in plasma samples were calculated by comparing cholesterol-cholestane peak height ratios with those of preassayed reference plasma. Over a plasma cholesterol range of 44 to 468 mg/100 ml, the gas-liquid chromatographic micromethod and the automated ferric chloride colorimetric method gave nearly identical results (r = 0.99) in duplicate aliquots of 131 plasma samples.

Diethylstilbestrol (DES) is readily extracted into toluene from biological fluids or tissue homogenates. Sodium carbonate is added to the initial mixture to eliminate potentially interfering substances. The toluene is extracted with a very small volume of aqueous trimethylphenylammonium hydroxide. This solution generates dimethyl DES in the vaporizer of a gas-liquid chromatograph. An internal standard, dienestrol (DI), is added at the beginning of the procedure and is partitioned and methylated in the same manner as DES. The DES and DI derivatives are well separated in less than 6 min on an ov-17 column. The entire analysis requires less than 15 min for a fluid specimen and less than 25 min for a solid tissue specimen. Seven samples can be analyzed each hour on a single column with a flame ionization detector. The relative standard deviations at levels from 2.5 to 100 ppm in bile are less than 5%. The lower limit of sensitivity is 8 ppb in a 1 ml bile sample.

Fatty acids were analyzed by a new method which involved their isolation from hexane extracts of serum or brain tissue in aqueous potassium hydroxide (10 microliter) and methylation directly in this solution with methyl iodide. The resulting fatty acid methyl esters were partitioned into ethylene chloride (25 microliter) and were quantitated by gas-liquid chromatography. The procedure was documented by comparison with conventional methylation reactions on serum fatty acids. This method, which avoids thin-layer chromatography and which measures individual free fatty acid concentrations in 20-mg brain tissue samples, should be of particular value for examining regional free fatty acids in brain following ischemia and trauma.

Adult rats received one fifth of their measured daily food consumption until they lost 40% body weight. Some of these rats were then refed until they reached their initial body weight. We measured the following in fed, starved, and refed animals: (1) disaturated phosphatidylcholine (DSPC) content of lung tissue and of lavage fluid, (2) protein content of lung tissue and of lavage return, and (3) DNA and RNA content of lung tissue. In starved lungs, tissue and lavage DSPC content, total protein and RNA contents, and RNA/DNA ratios were significantly lower than in fed rats. After refeeding, DSPC values returned completely to normal, whereas protein, DNA, and RNA contents were significantly higher than in fed rats. The RNA/DNA ratio was similar in the fed and refed groups. Changes in lavage DSPC are consistent with the increased surface elastic forces in starvation and their return to normal with refeeding reported by us previously. It appears that starvation leads to a reduction in cell size without changes in cell number and that refeeding is associated with a more significant increase in cell number than in cell size.