Characterization of human malignant melanoma cell lines. VII. Glycoprotein synthesis and shedding as revealed by [3H]glucosamine labeling

We have established conditions for the study of membrane glycoprotein synthesis and turnover in cultured human malignant melanoma cell lines using the labeled precursor [3H]glucosamine. Uptake of label increased parallel with cell growth, reaching a steady state in resting cultures. Fifteen to 30% of incorporated label can be released from the cells by trypsin treatment depending on the conditions of exposure to the enzyme, and about 50% of the incorporated label is spontaneously shed from the cells within 96 hr of incubation. Labeling in exhausted medium gave a 5- to 8-fold increase in uptake which was inhibited by addition of glucose (2 mg per ml) into the culture medium. The percentage of trypsin-releasable material was identical in fresh and exhausted medium; however, the percentage shed was less in cells initially labeled in exhausted medium. These data provide background information for further studies on the antigenic composition of the glycoproteins of cultured melanoma cells.     

Intra-arterial bolus of 125I labeled meglumine diatrizoate. Early extravascular distribution

A mixture of 125I labeled meglumine diatrizoate and 131I labeled human serum albumin was injected into the lower abdominal aorta of 30 anesthetized, laparotomized male rats. Measurements of the activities in cardiac blood and in different tissues of the hindlimbs and tests were perfomed at six time intervals ranging from 5 seconds to 2 minutes after injection, the determine early uptake and distribution volumes of diatrizoate. Concentrations and distribution volumes were initially much greater than values obtained after intravenous injection, but these differences had considerably decreased or disappeared by 2 minutes.     

Messenger RNA for renal phosphoenolpyruvate carboxykinase (GTP). Its translation in a heterologous cell-free system and its regulation by glucocorticoids and by changes in acid-base balance

A translational assay was used to measure the level of mRNA coding for phosphoenolpyruvate carboxykinase (GTP) (EC 4.1.1.32) in the rat kidney in various conditions in which the enzyme is induced. RNA extracted from whole kidneys was chromatographed on oligo(dT)-cellulose to select poly(A)-containing RNA. This crude mRNA preparation was able to stimulate amino acid incorporation into protein in a cell-free system containing an extract of wheat germ. Phosphoenolpyruvate carboxykinase could be detected among the polypeptides synthesized and quantitated by immunoprecipitation with a monospecific antibody followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amount of enzyme synthesized was proportional to the quantity of RNA added. The level of mRNA coding for phosphoenolpyruvate carboxykinase is increased 3-fold 6 h after triamcinolone injection. Translatable enzyme mRNA also increases 3-fold within 6 h of the onset of metabolic acidosis caused by an ammonium chloride load. In both cases, the increase in functional mRNA is commensurate with the stimulation of enzyme synthesis measured in vivo. Glucocorticoid administration and acidosis cause additive increases in the level of translatable phosphoenolpyruvate carboxykinase mRNA. The inductive effect of acidosis is preserved in the absence of the adrenals, hypophysis, thyroid, and parathyroids.     

Insulin, glucagon, portal systemic shunting, and hepatic failure in the dog

The cerebrospinal fluid (CSF) composition was studied in 54 premature infants. The pregnancy was normal and the delivery normal and non traumatic in all of them, and the 5 minutes Apgar score ranged from 6 to 9. No abnormalities were found on physical examination including neurological examination. Blood cell countings and blood gasometry were normal. CSF composition was studied as to: total cell count and total protein, glucose, bilirrubin and hemoglobin concentrations. Data found permit to stablish as physiologic the following values: leucocytes, until 16 per cumm; erithrocytes, until 1,280 per cumm; total protein content until 300 mgm/100 ml; bilirrubin until 80 micrometer/1; hemoglobin until 8 micrometer/1; glucose, two thirds of the concentration found in the blood. Protein, bilirrubin and hemoglobin are significantly increased as compared to values found for the CSF of 79 fullterm normal newborn babies evaluated previously. Hemoglobin was not detected in the CSF of any full term newborn baby. The differences found are probably due to a less efficient blood-CSF barrier in premature infants as compared to full-term newborn babies.     

Real-time monitoring of events applied to syndromic surveillance

Abstract

This article focuses on monitor plans aimed at the early detection of the increase in the frequency of events. The literature recommends either monitoring the time between events (TBE) if events are rare or counting the number of events per unit non-overlapping time intervals otherwise. Some authors advocate using the Bernoulli model for rare events, applying presence or absence of events within non-overlapping and exhaustive time intervals. This Bernoulli model does improve the real-time monitoring assessment of these events compared to counting events over a larger interval, making them less rare. However this approach became inefficient if more than one event starts occurring within the intervals. Monitoring TBE is the real-time option for outbreak detection, because outbreak information is accumulated when an event occurs. This is preferred to waiting for the end of a period to count events. If the TBE reduces significantly, then the incidence of these events increases significantly. This article explores this TBE option relative to using the monitoring of counts when the TBEs are either Exponentially, Gamma or Weibull distributed for moderately low count scenarios. The article will discuss and compare the approaches of using an Exponentially Weighted Moving Average (EWMA) statistic for the TBEs to the EWMA of counts. Several robust options will be considered when the future change in event frequency is unknown. Our goal is to have a robust monitoring plan which is able to efficiently detect many different levels of shifts. These robust plans are compared to the more traditional event monitoring plans for both small and large changes in the event frequency.     

Gonadoblastoma: clinicopathologic correlation in six patients

Six patients with a total of nine gonadoblastomas are presented; three--and possibly a fourth--had dysgerminomatous overgrowth which was massive in two patients. Calcification detected by abdominal films was present in three sufficient for preoperative diagnosis. All patients were found to have a Y stem line on peripheral leukocyte chromosome cultures except one patient, who had a 46 XX/45 XO karyotype. She was found to have Y chromatin bodies in the germ cells of her tumor which was in a normal ovary found at exploration for an ectopic pregnancy. Three were found in virilized phenotypic females investigated for amenorrhea, and two for therapy of pelvic masses due to dysgerminomatous overgrowth. Y chromatin studies are reported on gonadal tissue.     

Low Temperature Water–Gas Shift Reaction Over Alkali Metal Promoted Cobalt Carbide Catalysts

Low temperature water–gas shift (LT-WGS) was performed over various group I alkali metal (Li, Na, K, Rb, Cs) promoted cobalt carbide (Co₂C) catalysts at temperatures ranging from 453 to 573 K and atmospheric pressure. Cobalt carbide (Co₂C) was found to be active for the WGS reaction. The stability of the catalyst is related to the stability of the cobalt carbide phases under reaction conditions. Potassium promoted cobalt carbide catalysts exhibited higher activity and stability compared to the other alkali promoted catalysts for LT-WGS. X-ray diffraction analyses of fresh and used catalysts suggest that the origin of deactivation of the catalysts is primarily due to the chemical transition of cobalt from carbide to metal during WGS.     

Extraction of Lipids from Municipal Wastewater Plant Microorganisms for Production of Biodiesel

Municipal wastewater treatment plants in the USA produce over 6.2 × 10⁶ t of dried sewage sludge every year. This microorganism-rich sludge is often landfilled or used as fertilizer. Recent restrictions on the use of sewage sludge, however, have resulted in increased disposal problems. Extraction of lipids from sludge yields an untapped source of cheap feedstock for biodiesel production. Solvents used for extraction in this study include n-hexane, methanol, acetone, and supercritical CO₂. The gravimetric yield of oil was low for nonpolar solvents, but use of polar solvents gave a considerably increased yield; however, the percentage of saponifiable material was less. Extraction of lipids with a mixture of n-hexane, methanol, and acetone gave the largest conversion to biodiesel compared with other solvent systems, 4.41% based on total dry weight of sludge. In situ transesterification of dried sludge resulted in a yield of 6.23%. If a 10% dry weight yield of fatty acid methyl esters is assumed, the amount of biodiesel available for production in the USA is 1.4 × 10⁶ m³/year. Outfitting 50% of municipal wastewater plants for lipid extraction and transesterification could result in enough biodiesel production to replace 0.5% of the national petroleum diesel demand (0.7 × 10⁶ m³).