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At least 19 recordsLinked to original sources
PubMed1977

Freezing and storage of breast cancer tissue for estrogen receptor protein assay: a convenient method.

Sixteen patients underwent biopsy of primary or metastatic breast cancer and had equal portions of the tumors rapidly frozen by either the use of liquid nitrogen or the fluorinated hydrocarbon spray, Cryokwik. The estrogen receptor protein (ERP) assay was then performed on both specimens, utilizing the surcose gradient density method. In general, both methods of freezing gave similar results. Three patients had ERP measured after approximately three to four months of storage at -70 C. After a minimum of 14 weeks' storage, there was no statistically significant loss of activity by either method of preparation. The Cryokwik preparation method makes the accurate measurement of ERP possible for all community hospitals. The tissue may be prepared and stored until a convenient time for transportation to the appropriate laboratory.

Breast Neoplasms↗
PubMed1977

[Toxicity of aliphatic halogenated hydrocarbons containing fluorine].

The fluorinated propellers have a certain cardiotoxicity. They cause disturbances to the intraventricular conduction, to the inotropisme and to the arterial pressure. Such disturbances show up in the laboratory rat due to a concentration in the air that once was thought innocuous for this specie. We have analysed doses of 15%-30%-60% of CCl2F2 in the air on the tracheotomysed and curarised animals. The vagotomy protects in part from the occurence of marked alterations ECG, but not from the alterations of the cardiac mechanigram and of the arterial pressure. The arterial pressure is the cardiocirculatory parameter which remains inhibited longer when the animal is again breathing air without Freon. After breathing air without Freon for ten minutes, rats submitted to a successive dose of gas are rapidly intoxicated. Low doses of CCl2F2 in the air (5%) make rabbits ipersensitive to the "arythmies-producing" effects of the adrenaline.

Aerosol Propellants↗
PubMed1979

Potential halogenated industrial carcinogenic and mutagenic chemicals. II. Halogenated saturated hydrocarbons.

The halogenated saturated hydrocarbons analogously to the previously considered halogenated unsaturated hydrocarbons (Part I) possess considerable utility in a broad spectrum of applications including; solvents, dry-cleaning fluids, refrigerants, fumigants, degreasing agents, propellants and intermediates in the production of other chemicals, textiles and plastics. Methyl chloride, methylene chloride, chloroform, carbon tetrachloride, methyl chloroform, 1,1,2-trichloroethane, hexachloroethane, ethyl chloride and fluorocarbons were reviewed principally in terms of their synthesis (or occurrence), areas of application, stability, distribution, reactivity, levels of exposure, populations at risk, carcinogenicity, mutagenicity and metabolism.

Animals↗
PubMed1977

Halogenated hydrocarbons in the atmosphere.

The sources, sinks, and tropospheric abundancies of the gaseous halocarbons, so far as they are known, are listed and discussed. The relative importance of natural and of man-made halocarbons is discussed within the context of contemporary concern about the depletion of stratospheric ozone by chlorine-bearing compounds.

Atmosphere↗
PubMed1975

Short-term inhalation toxicity of halogenated hydrocarbons: effects on fasting rats.

Male rats, fasted overnight (18 hours), and exposed to various materials in inhalation were more sensitive to the hepatotoxic effects of carbon tetrachloride, 2-chlorobutadiene, 1,1-dibromoethylene, and 1,1-dichloroethylene (DCE). Vinyl chloride monomer and 1,1-difluoroethylene were not acutely hepatotoxic in fed or fasted rats at any concentration tested. Vinyl chloride monomer when administered simultaneously with DCE prevented the injury associated with DCE inhalation in fasted rats. This prevention of injury may be a result of a competitive interaction since the effect was concentration dependent.

Aerosols↗
PubMed1975

The effects of diethyl ether, enflurane, and isoflurane at the neuromuscular junction.

The actions of diethyl ether, enflurane, and isoflurane at the neuromuscular junction were examined in isolated guinea pig lumbrical muscles. These anesthetics depressed the ability of carbachol to depolarize the endplate region; this depression of depolarization did not show competitive kinetics. None of the anesthetics altered the affinity of the acetylcholine receptor for d-tubocurarine, i.e., the dissociation constant of d-tubocurarine was unchanged. Since diethyl ether, enflurane, and isoflurane produced no observable alteration of the receptor, the antagonism of the drug-induced depolarization of the neuromuscular junction appears to be exerted at a stage subsequent to reaction with the receptor. (Key words: Anesthetics, volatile, diethyl ethers; Anesthetics, volatile, euflurane; Anesthetics, volatile, isoflurane; Neuromuscular relaxants, d-tubocurarine; Neuromuscular junction.).

Acetylcholine↗
PubMed1975

Metabolism in vitro of enflurane, isoflurane, and methoxyflurane.

Specific activities of enflurane, isoflurane, and methoxyflurane defluorinases were measured in microsomes prepared from the livers of Fischer 344 rats; the ratio of these activities was 23:3:1. Pretreatment with phenobarbital significantly increased the defluorinase activities of all three agents. Factors that influence anesthetic drug metabolism are discussed; tissue solubility is considered to be the most important.

Anesthesia, Inhalation↗
PubMed1975

Alternate cryogens for cryosurgery.

There is need for a storable cryogen suitable for use in dermatological cryosurgery as an alternate for the standard nonstorable cryogen now used (liquid nitrogen). Argon gas was tested and found satisfactory, but has not proved to be commercially feasible. Nitrous oxide apparatus is now available but is of limited usefulness. Various freons (fluorinated hydrocarbons) present possibilities for our use. Although they are incapable of producing the degree of cold and depth of penetration attainable with liquid nitrogen apparatus, they can be used to treat the vast majority of lesions now treated by cryosurgery in an office-based dermatological practice. Freons 12, 22 and 13, alone or mixed with other gases, have been tested. Freon 22 seems the most practical for general dermatologic cryosurgery. Although these gases are considered relatively non-toxic, at this time we really do not know their total noxious capabilities.

Chlorofluorocarbons, Methane↗
PubMed1979

Dependency upon salbutamol inhalers.

A case of dependency on salbutamol inhalers has been described. This has been discussed in relation to abuse of other drugs by alveolar absorption and other effects of salbutamol. It is not known whether the dependency is due to the salbutamol itself or to the fluorinated hydrocarbons used as propellants.

Adult↗
PubMed1977

Toxicology of the fluoroalkenes: review and research needs.

In this review of the published literature on the toxicology of fluoroalkenes several features emerge and research needs are evident. The fluoroalkenes vary widely in acute inhalation toxicity. Those, such as perfluoroisobutylene, PFIB, the most highly toxic member, attacks the pulmonary epithelium of rats eventuating in edema and death after a delay of about one day. Other fluoroalkenes, such as hexafluoropropylene (HFP) or chlorotrifluoroethylene (CTFE), also cause pulmonary injury but at lower concentrations produce concentration dependent changes in the renal concentrating mechanism of the rat. Changes in the CNS of rats and rabbits have also been reported for CTFE. CTFE, in repeated exposures, has produced blood pressure changes in dogs, CNS effects and changes in the erythropoietic system. This variety of responses indicates the need for investigation. Chronic effects have not been sufficiently studied for PFIB and HFP. Thus pointing up the desirability for study. Mechanisms of action research for fluoroalkenes is an important area of need. While several ideas have been suggested, there are no data to support them. The nucleophilic sensitivity of the fluoroalkenes and the potential carcinogenic effects stemming therefrom suggests a need field for investigation. We also can readily perceive the needs for the evaluation of effects on reproduction (including mutagenesis and teratogenesis), metabolism pulmonary functions, cellular function and structure. Epidemiologic studies on occupationally exposed populations are desirable in order to adequately define human health hazard from these fluorocarbons.

Alkenes↗
PubMed1975

Clinical trail of intravitreal C F in retinal detachment surgery.

A mixture of 40% octafluorocyclobutane (C4F8) and 60% air was used clinically in eight patients with long-standing retinal detachment. In seven cases the retina reattached after intravitreal injection of C4F8 and intrascleral diathermization of the retinal tear. The one failure was due to massive vitreous retraction and preretinal proliferation prior to the surgery. Except for a slight postoperative iritis when 4 cc of gas lasted for 12 to 30 days after intravitreal injection. On the basis of this and our previous studies, we recommend the use of C4F8 in retinal detachment surgery.

Adult↗
PubMed1975

MAC expanded: AD50 and AD95 values of common inhalation anesthetics in man.

Two important measures may be derived from patient responses to a range of anesthetic doses. The AD50, corresponding to MAC, estimates the median anesthetic concentration--that dose where half the patients are anesthetized and half are not. The AD95 approaches the theoretical "minimum" anesthetic concentration by estimating the dose that anesthetizes 95 per cent of a patient population. The AD50 and AD95 are logical extensions of the MAC concept and can be evaluated with current experimental methodology. Recomputed from available data , the AD50's of nine inhaled anesthetics proved to be numerically identical to their MAC values. The AD95's of nine inhaled anesthetics proved to be numerically identical to their MAC values. The AD95's were 5 to 40 per cent greater than the AD50's.)Key workd: Potency, anesthetic, MAC, AD50, AD95; Pharmacology, dose-response curves.)

Anesthesia, Inhalation↗
PubMed1977

Fluorine-18-labeled diethylaminosulfur trifluoride (DAST): an F-for-OH fluorinating agent.

A new fluorinating agent was developed by incorporation of 18F into diethylaminosulfur trifluoride (DAST), a reagent capable of replacing hydroxyl and carbonyl oxygen with fluorine. The DAST was synthesized using sulfur tetrafluoride and trimethylsilyldiethylamine in a freon-11 solvent at -78 degrees C and purified by reduced-pressure distillation. Labeling was then accomplished by exchange with anhydrous 18F-hydrofluoric acid, which caused more than 80% of the available activity to be incorporated into the DAST. Fluorine-18-labeled methyl fluoride, ethyl fluoride, and 2-fluoroethanol were prepared from methanol, ethanol, and ethylene glycol, with yields of 20%, 25%, and 12%, respectively.

Ethanol↗
PubMed1977

The insufflation of freon in vitreoretinal surgery.

Among the various gases recommended for intravitreal injection, sulfur hexafluoride (SF6) and octafluorocyclobutane (C4F8) are the most commonly used. The purpose of the injection is to restore the vitreous chamber after drainage of subretinal fluid or after vitrectomy. Some of the fluorinated hydrocarbons which belong to the group known as Freon (a registered trademark) have previously been used in the animal with the same end in view. Of these, Freon-12 and Freon-114 were selected on account of their physical properties, the fact that they remain in the vitreous cavity for 4-14 days, their availability and their innocuousness, and used in humans as an adjunct to vitreoretinal surgery. The results are compared to those obtained with other halogenated gases.

Animals↗