Liquid Infusion Research Articles

Comparisons of the Disappearance of Ytterbium-169, Chromium-51, and Intrinsically Carbon-14-Labeled Plant Cell Walls from Continuously Fed Fermentors ,

An experiment was conducted with labeled wheat plant cell walls intrinsically labeled with 14C and treated with extrinsic markers to measure their rate of disappearance from fermentors fed every hour. The systems were maintained at pH 7.0 in the first trial and at pH 2.5 in the second trial to mimic acidities for the rumen and abomasum. In each trial 12 fermentors were fed hourly .4 or .8g orchardgrass hay pellets, infused continuously with 500 or 1000ml of buffered solution daily, and dosed with three marked cell wall treatments. Treatments were 1) 14C cell walls, 2) 14C cell walls mordanted with Cr containing tracer 51Cr, and 3) 14C cell walls treated with Yb containing tracer 169Yb. Marker disappearance was faster at pH 7.0 than at pH 2.5. Marker disappearance was faster for the high than the slow liquid infusion rate. Disappearance was also faster for the high feed rate than the low feed rate. Fractional rates of 14C cell wall disappearance (h−1) were −.042, −.035, and −.029 in the untreated, Yb-treated, and Cr-treated cell walls, and rates of 169Yb and 51Cr disappearance were −.039 and −.025, respectively. Treating 14C cell walls (internal control) with Cr or Yb reduced disappearance compared to nontreated 14C cell walls (external control). Differences in rates of marker disappearance and interactions of markers, pH, infusion, and feed rates support the need for caution in interpretation of kinetic data in general and comparison of results obtained with different markers.

Liquid-Metal Corrosion

A review of corrosion and environmental effects on the mechanical properties of candidate structural alloys for use with liquid metals infusion reactors is presented. The corrosion/mass transfer behavior of austenitic and ferritic steels and vanadium-base alloys is evaluated to determine the preliminary operating temperature limits for circulating and static liquid-lithium and Pb-17Li systems. The influence of liquid-metal environment on the mechanical properties of structural materials is discussed. Corrosion effects of nitrate and fluoride salts are presented. Requirements for additional data are identified.

Production and partial purification of a peptide antibiotic from Staphylococcus epidermidis.

When grown on solid or in liquid Brain Heart Infusion at 37 degrees C, Staphylococcus epidermidis NCIB 11536 produced antibiotic activity against a wide range of Gram positive bacteria. Production was influenced by aeration, pH, glucose concentration and specific growth rate. Inhibitory activity could be concentrated by ammonium sulphate precipitation (30-55% saturation). On Sephadex G50 using 0.05 mol/l sodium phosphate buffer, pH 6.0, two peaks of antibiotic activity were detected. The first peak eluted with the void volume (Kd = 0) and the second peak was retained by the gel (Kd = 0.73-0.77). These two substances did not represent the monomeric and polymeric forms of a staphylococcal bacteriocin. The low mol. wt inhibitor, which was responsible for over 95% of the recovered activity on Sephadex G50, could be partially purified by a combination of gel filtration on Biogel P2 and ion-exchange chromatography on Sephadex C-25. Yields were increased by combining these two steps into a single procedure (duocolumn). The semi-purified inhibitor was desalted using Sep-pak C18 cartridges. Biological activity was resistant to enzymic denaturation except by high concentrations of trypsin (50 units/micrograms, 3 h, 25 degrees C). This peptide antibiotic is different from any previously described staphylococcal inhibitors.

Prevention of re-obliteration after reconstructive surgery on the fallopian tubes

In order to prevent infection and prevent sticking of the fallopian tubes from the first hours after the end of the operation, we used continuous irrigation of the tubes. To do this, immediately before the operation, a self-contained tip was introduced into the cervical canal, through which, after opening the abdominal cavity, a sterile saline solution stained with indigo carmine (chromohydzotubation) was injected, which made it possible during the operation to more accurately determine the state of the fallopian tubes, etc. control the degree of restoration of patency. After the end of the operation, the tip was left in the uterus for 5-7 days. A system for drip infusion of liquids was attached to it. The procaine-furacillin mixture (0.1 g of furacillin, 9 g of sodium chloride, 2.5 g of novocaine, 1000 g of distilled water) was poured dropwise. To the initial solution was added 250 mg of hydrocortisone and 1500 units. heparin, however, their dose was gradually reduced in the following days.

Presence of dihydrostreptomycin and penicillin in cows' milk following intrauterine administration.

Cows were given liquid intrauterine infusions of dihydrostreptomycin and penicillin or dihydrostreptomycin alone approximately 24 hours after the onset of oestrus to determine the necessary withholding period for milk intended for human consumption. When dihydrostreptomycin and procaine penicillin were administered together, a withholding period of 72 hours provided an adequate safety margin. Thirty-six hours was an adequate withholding period when dihydrostreptomycin was administered.

Spectrum of Microbial Keratitis in South Florida

During a nine-year period ending in 1977, we scraped and cultured 663 corneal ulcers. Of these cases of keratitis, 238 were bacterial infections, 133 were fungal, and 292 were culture-negative. Pseudomonas was the predominant bacterial organism, and Fusarium was the most common fungus isolated. November was the peak month for both bacterial and fungal keratitis. Direct inoculation of multiple media, including Sabouraud's agar, blood agar, chocolate agar, thioglycollate liquid, and brain-heart infusion liquid, enhanced the recovery rate; each medium provides special nutrients for different organisms. The Gram and Giemsa stains were satisfactory, but the newer Grocott methenamine silver stain for fungi and the limulus lysate test for gram-negative bacteria proved to be clinically useful. The clinical profile of patients with fungal keratitis differed from that of patients with Pseudomonas keratitis. Thirty-three percent of the patients with Pseudomonas keratitis were wearing contact lenses at the time of their infection, and the remainder had a high incidence of predisposing ocular conditions. Fungal keratitis tended to occur in healthy male patients who had been subjected to outdoor trauma.

Pharmacologic studies of continuous infusion of arabinosylcytosine by liquid infusion system

Arabinosylcytosine (ara-C) was administered by prolonged intravenous infusion with a portable liquid infusion system (LIS) to patients with acute myelogenous leukemia. With the use of tritiated ara-C and this portable system, pharmacologic studies were performed in 8 patients. Most of the plasma radioactivity is in the deaminated product, arabinosyluracil (ara-U). After continuous intravenous infusion, a constant ara-C level is achieved slowly in the plasma. Unless a loading (priming) dose is administered immediately before beginning the infusion, a steady-state ara-C level cannot be achieved until 8 to 24 hr after the infusion. The infusion system has two mechanisms--one for giving a loading dose (3 ml/min) and the other for regular infusion at a rate of 0.5 to 2.0 ml/hr. If a loading dose is given before continuous infusion, a steady-state are-C level is achieved within an hour. The plasma ara-C disappearance curves are biphasic with a terminal half-life of 104 min, which is the same as that of a single injection. The cumulative urinary excretion after approximately 23 hr of infusion varied from 14% to 35% in different patients; more than 90% is ara-U and the remainder is ara-C. Our results have demonstrated that LIS can be used conveniently to sustain a constant plasma level of ara-C. The LIS increases mobility of both inpatients and outpatients and is particularly convenient for ambulatory patients.

Supraventricular arrhythmias caused by parenteral hyperalimentation

PARENTERAL hyperalimentation has been used in the treatment of malnutrition resulting from the patient's inability to eat.¹In recent years, many such patients have benefitted dramatically from the intravenous infusion of liquids containing both glucose and amino acids. Some complications have been described, including hyperglycemia and osmotic diuresis, hypoglycemia following discontinuance of therapy, thrombophlebitis secondary to catheter placement, and electrolyte imbalance.²The following is a case report of a patient who exhibited a previously unreported complication, supraventricular arrhythmias. <h3>Report of a Case</h3> A 68-year-old woman with a lengthy history of peptic ulcer disease and a previous gastrectomy with gastroileostomy was admitted to the hospital. She complained of weight loss and vomiting of approximately three weeks' duration. Upper gastrointestinal roentgenograms showed a marginal ulcer at the edge of the efferent loop of the gastroileostomy, as well as extensive edema of the surgical stoma with almost total obstruction. Accordingly, a

Supraventricular Arrhythmias Caused by Parenteral Hyperalimentation

PARENTERAL hyperalimentation has been used in the treatment of malnutrition resulting from the patient's inability to eat.¹In recent years, many such patients have benefitted dramatically from the intravenous infusion of liquids containing both glucose and amino acids. Some complications have been described, including hyperglycemia and osmotic diuresis, hypoglycemia following discontinuance of therapy, thrombophlebitis secondary to catheter placement, and electrolyte imbalance.²The following is a case report of a patient who exhibited a previously unreported complication, supraventricular arrhythmias. <h3>Report of a Case</h3> A 68-year-old woman with a lengthy history of peptic ulcer disease and a previous gastrectomy with gastroileostomy was admitted to the hospital. She complained of weight loss and vomiting of approximately three weeks' duration. Upper gastrointestinal roentgenograms showed a marginal ulcer at the edge of the efferent loop of the gastroileostomy, as well as extensive edema of the surgical stoma with almost total obstruction. Accordingly, a

A device for the chronic intra-ventricular infusion in freely moving rats.

A simple device for the chronic infusion of solutions and pure liquids into the cerebral ventricles of freely moving animals is described. Its construction, implantation and preparation for use are given in detail.

Preoptic temperature during oral and intragastric feeding

Preoptic brain temperatures of rats were recorded during oral and intragastric feeding. Oral ingestion of solid dry food was the only treatment that significantly increased preoptic temperature. Oral ingestion of liquid food and infusion of either liquid food or water directly into the stomach via a cannula failed to produce a significant change in brain temperatures. These data are not consistent with Brobeck’s (1951) thermoregulatory hypothesis which predicts that both ingested and infused liquid nutrients should also increase preoptic temperature.