Measurement of cefoxitin levels in tissue using high-pressure liquid chromatography.

A high-pressure liquid chromatography (HPLC) method that successfully measured cefoxitin (a modification of the antibiotic cephamycin C) levels in subcutaneous tissue, muscle, and aortic and peripheral arterial walls has been developed. Samples were obtained from 11 patients submitted to prosthetic aortic replacement. All patients received an intravenous bolus dose of cefoxitin 2 g just before induction of anaesthesia. Blood and tissue samples were taken at various intervals intra-operatively. The tissue samples were mechanically homogenised. Both plasma and the tissue homogenates were deproteinated with trichloracetic acid. The cefoxitin was separated by HPLC and measured by ultraviolet absorbance. The results show that the tissue concentration of the drug fell over a 4-hour period and that all levels exceeded the MIC90 (minimum inhibitory concentration that inhibits growth of bacteria at the 90% level) for most aerobic and anaerobic pathogens for at least 3 hours.

Correlation between concentrations of magnesium, zinc, and potassium in plasma, erythrocytes and muscles.

In 93 patients, consecutively subjected to laparotomy, we studied the correlation between concentrations of magnesium, zinc and potassium in plasma, erythrocytes and muscle tissue. Sixteen percent had hypomagnesemia, 27% hypozincemia, and 53% hypokalemia. There was no difference with regard to the concentration of magnesium and zinc in erythrocytes or in muscle tissue between patients with low and patients with normal/high plasma concentrations of these minerals. Potassium concentration per liter erythrocytes was slightly but significantly higher in patients with hypokalemia than in patients with normal plasma potassium. When expressed per mmol haemoglobin there was, however, no difference in erythrocyte potassium between these two groups. Neither did they differ with regard to potassium concentration in muscles. There was a highly significant correlation between the concentrations of magnesium, zinc and potassium in erythrocytes as well as in muscle tissue, and a significant correlation between magnesium and potassium in plasma. However, no correlation was found between the mineral concentrations in plasma, erythrocytes and muscles, neither for magnesium, nor for zinc or potassium. We therefore conclude that a valid test to estimate total body stores of these minerals cannot be based on analysis of erythrocytes.

Pharmacokinetics of single dose intravenous ciprofloxacin in patients undergoing gastrointestinal surgery.

The pharmacokinetics of single dose intravenous ciprofloxacin in patients undergoing gastrointestinal surgery (100 mg, n = 8; 200 mg n = 18) have been studied. Following 100 mg therapeutic serum levels were maintained for approximately 40 min only and tissue concentrations were frequently less than 0.15 mg/kg. 200 mg maintained therapeutic serum levels for at least 150 min and produced mean concentrations in fat, muscle, peritoneum and gut wall of 1.04, 1.94, 1.59, and 3.39 mg/kg respectively. 200 mg iv ciprofloxacin would appear to provide adequate serum and tissue concentrations for at least 150 min.

[Specific glucocorticoid receptors of human muscle cytosol]. / Spetsificheskie gliukokortikoidnye retseptory tsitozolia myshtsy cheloveka.

The level of specific type II and III glucocorticoid receptors was measured in biopsy specimens taken from the abdominal rectal muscle of patients operated on the abdominal cavity organs for chronic diseases of the biliferous tract or peptic ulcer of the stomach in the stage of remission. Type II glucocorticoid receptors were determined with the aid of labeled triamcinolone acetonide whereas type III glucocorticoid receptors with the aid of labeled cortisol after preliminary elimination of endogenous glucocorticoids from cytosol. The content of type II glucocorticoid receptors in muscle tissue cytosol amounted to 11.7 fmol/mg protein, whereas the dissociation constant of the hormone-receptor complex to 1.346 X 10(-8) M. The content of type III glucocorticoid receptors in muscle tissue cytosol was equal to 114 fmol/mg protein, the dissociation constant of the hormone-receptor complex to 0.30 X 10(-8)M. The hypothesis of antiglucocorticoid role of type III glucocorticoid receptors is discussed.

The muscles of the abdominal wall: a new functional approach with anatomoclinical deductions.

The basic functional anatomy of muscle can be investigated by histochemical analysis of the muscle fibers and kinesiologic electromyography. The results of these techniques lead to anatomoclinical deductions based on the structure of muscle. Histochemical analysis of the striated fibers of a given muscle shows the existence of three functionally different populations of fibers. The relative abundance of each category of muscle fibers (expressed as a percentage) demonstrates the basic function of the muscle. The investigation of muscle function by kinesiologic electromyography shows that there are three categories of motor activity in the course of movement. These different types of motor activity are dependent upon the muscle fibers which display different physiological features, especially with respect to their contraction time. These two investigative techniques, the overall results of which are concordant, were applied to the study of the function of the muscles of the abdominal wall and led to the following anatomo-clinical deduction: tonico-postural motor activity is predominant in the rectus abdominis and flat abdominal muscles. Kinesiologic electromyography also allowed to demonstrate the functional development of these muscles according to the age, sex, corpulence and physical activity of the subjects studied.

The relationship of cimetidine to 5-hydroxytryptamine tissue levels in stress ulceration in the rat.

We studied the effect of cimetidine on 5-hydroxytryptamine (5-HT) levels in various tissues in restrained rats. Sixty male Sprague-Dawley rats, divided into four groups, received four intraperitoneal injections at 6-hour intervals in doses determined by body weight. Group I (control) was injected with saline (1 ml/300 gm) and was not restrained. Group II was injected with saline (1 ml/300 gm) and restrained for 18 hours beginning 1 hour after the first injection. Group III was injected with cimetidine (100 mg/kg) and was not restrained, whereas Group IV was injected with cimetidine (100 mg/kg) and restrained according to the schedule for Group II. The rats were killed and their stomachs were collected and graded for ulceration. 5-Hydroxytryptamine levels in the antrum and fundus of the stomach, the colon, the liver, and rectus abdominis muscle were determined by spectrophotofluorometry. Cimetidine prevented an increase in 5-HT in the antrum and protected against ulceration. As 5-HT levels in other tissues were not altered by restraint-induced stress, the phenomenon may be specific to the antrum. The protection against ulceration and elevated 5-HT levels conferred by cimetidine was comparable to that of vagotomy in similar models.

Identification of normal rat organs by two-dimensional protein electrophoresis.

Proteins from nine normal rat organs, including heart, lung thymus, liver, spleen, kidney, prostate, abdominal muscle, and brain, were solubilized, separated by electrophoresis according to their different isoelectric points and molecular weights, and stained with Coomassie blue. Patterns of major proteins unique to each organ were identified. Nine "unknown" samples, chosen from the same sources and submitted for analysis in a single blind study, were easily identified by comparing their protein profiles against the nine "reference" patterns. The ability to identify the origin of a tissue sample without recourse to microscopy, by comparing the pattern of its electrophoresed proteins with a "catalogue" of identified protein profiles, provides a prototype for the identification of histologically indeterminate normal and abnormal cells, tissues, and organs. Application of this technique to problems in human pathology and forensic medicine could prove to be very useful.

Electrophoretic analysis of proteins from single bovine muscle fibres.

A number of single fibres were isolated by dissection of four bovine masseter (ma) muscles, three rectus abdominis (ra) muscles and eight sternomandibularis (sm) muscles. By histochemical criteria these muscles contain respectively, solely slow fibres (often called type I), predominantly fast fibres (type II), and a mixture of fast and slow. The fibres were analysed by conventional sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and the gels stained with Coomassie Blue. Irrespective of the muscle, every fibre could be classed into one of two broad groups based on the mobility of proteins in the range 135000-170000 daltons. When zones containing myosin heavy chain were cut from the single-fibre gel tracks and 'mapped' [Cleveland, Fischer, Kirschner & Laemmli (1977) J. Biol. Chem. 252, 1102-1106] with Staphylococcus proteinase, it was found that one group always contained fast myosin heavy chain, whereas the second group always contained the slow form. Moreover, a relatively fast-migrating alpha-tropomyosin was associated with the fast myosin group and a slow-migrating form with the slow myosin group. All fibres also contained beta-tropomyosin; the coexistence of alpha- and beta-tropomyosin is at variance with evidence that alpha-tropomyosin is restricted to fast fibres [Dhoot & Perry (1979) Nature (London) 278, 714-718]. Fast fibres containing the expected fast light chains and troponins I and C fast were identified in the three ra muscles, but in only four sm muscles. In three other sm muscles, all the fast fibres contained two troponins I and an additional myosin light chain that was more typical of myosin light chain 1 slow. The remaining sm muscle contained a fast fibre type that was similar to the first type, except that its myosin light chain 1 was more typical of the slow polymorph. Troponin T was bimorphic in all fast fibres from a ra muscles and in at least some fast fibres from one sm muscle. Peptide 'mapping' revealed two forms of fast myosin heavy chain distributed among fast fibres. Each form was associated with certain other proteins. Slow myosin heavy chain was unvarying in three slow fibre types identified. Troponin I polymorphs were the principal indicator of slow fibre types. The myofibrillar polymorphs identified presumably contribute to contraction properties, but beyond cud chewing involving ma muscle, nothing is known of the conditions that gave rise to the variable fibre composites in sm and ra muscles.

[Experimental studies of the distribution of intravenously injected iodine-labeled cytonal (diethylstilbestrol diphosphate)]. / Experimentelle Untersuchungen über die Verteilung von intravenös injiziertem jodmarkiertem Cytonal (Diäthylstilböstroldiphosphat).

After intravenous injection the distribution of iodine-labelled diethylstilbestral-diphosphate (cytonal) was investigated in various organs of the rat. For this purpose the concentration of activity in the organs of the animals were established by measurements of specimens in the bore-hole counter and scintigrams were made by means of a small animal scanner. The result was an unequivocal temporary dependence of the enrichment of the substance in the organs. The greatest enrichment was found 10 minutes after injection in the liver, then followed blood, kidneys, adrenal glands, seminal vesicles, prostate, abdominal wall and the fatty tissue surrounding the prostate. The blood activity relatively decreased. 7 days after injection an unambiguously higher activity was to be proved in the liver, kidney, adrenal gland than in the blood, whereas the enrichment of iodine-labelled diethylstilbestraldiphosphate in prostate, seminal vesicle, fatty and muscular tissue was always below the enrichment of the blood. But in every case the relation of organ activity to blood activity changed in favour of the organ activity, also with regard to the prostate. 10 minutes after injection the concentration of the activity of the seminal vesicle was somewhat higher than that one of the prostate, but in the further course it was below the concentration of the activity of the prostate. During the first two hours the fatty tissue surrounding the prostate showed a clearly and after the third day a slightly lower activity concentration than the prostate. On the basis of this distribution of the activity for the scintigraphy of the prostate above all a temporary interval of about 10 minutes to 3 hours after the injection of labelled cytonal is involved. The results cause us to perform investigations in men concerning the pharmacokinetics and the possibility of using radioactively labelled cytonal.

[IR-spectra of skeletal muscle mitochondria and endoplasmic reticulum]. / Osobennosti IK-spektrov mitokhondrii i éndoplazmaticheskogo retikuluma skeletnoi myshtsy

The existance of alpha- and beta-protein conformation in human straight abdomen muscle mitochondria and microsomal fraction was established. The stability of beta-conformation was provided by hydrophobic and lipid protein interactions. The band at 1730 cm-1, C=O stretching of the carboxyl groups, was more intensive in mitochondria, presented in microsomal fraction and disappeared after its isooctane treatment. From the reducing of NH, OH stretching frequency in microsomes films, was made a conclusion that hydrogen bonds were stronger in that membrane.

Lipolysis as a function of cell numbers and fat content: comparison between isolated rat and dog adipocytes.

The lipolytic responses to dihydroergotamine (5 mug/mi) of isolated rat adipocytes andto epinephrine (50 ng/m1 and 1 mug/m1) of both rat and dog adipocytes were measured over a period of two hours. Glycerol release was calculated as a function of either glycerol ester content or of cell number per incubation vial. The conventional calculation based on glyceride content gave the following results: a) epididymal fat cells from rats weighing less than 160 gm were more sensitive to dihydroergotamine and epinephrine than were fat cells from heavier animals weighing close to 200 gm; b) dog adipocytes from abdominal subcutaneous tissue were less sensitive to eipnephrine than were rat adipocytes. No such differences were noted when the same data were calculated on the basis of cell numbers per incubation vial: the lipolytic response was uniform with rat adipocytes obtained either from the lighter or the heavier weight groups, and so was the response of dog and rat cells. These results indicate that in the type of studies where receptor-dependent hormone and drug effects are measured, the number of cells per incubation vial is an important parameter to be considered in evaluating a lipolytic response.

[Quantitative K and Na levels in different parts of the heart in cases of sudden death from coronary disease, acquired heart valve defects and violent death]. / Kolichestveno sudurzhanie na K i Na v razlichnite uchastutsi na surtseto v sluchai na skoropostizhna smurt ot koronarna bolest, pridobiti klapni porotsi na surtseto i nasilstvena smurt

The quantitative potassium and sodium contents in the separate regions of the heart and m. rectus abdominis in cases of sudden and violent death were investigated. The disturbances of the electrolyte metabolism of potassium and sodium were established to be the earliest changes in coronary disease (acute coronary insufficiency resulting from functional disturbances of the coronary circulation and myocardial infarction). The decrease of the quantitative potassium contents and sodium increase in myocardium depend on the ischemia duration and the stage of the myocardial lesion. The highest potassium decrease was observed in the left ventricle and right auricle. Not very high but even decrease of potassium and sodium contents in the separate heart regions was observed in the deceased by electrocution and strangulation, the decrease being most negligible in the deceased by electrocution. The changes observed in potassium and sodium contents are not pathognomic signs of coronary disease. Only the sharp, focal decrease of the contents of those element is a reliable sign of myocardial infarction.

The mechanism of plasticization of the abdominal cuticle in Rhodnius.

1. The mechanism of plasticization of the abdominal cuticle in Rhodnius larvae has been investigated, using the properties of loops of cuticle under varying test conditions as a model for the behaviour of the cuticle in vivo. 2. It is supposed that plasticization is effected by a change in the intracuticular environment. A number of model mechanisms for plasticization may be proposed, which suppose that the epidermis is capable of regulating (a) pH, (b) ionic strength,(c) Ca and/or Mg, (d) urea, within the cuticle. 3. Analyses of cuticle ash show that models(b) and (c) are not responsible for plasticization in vivo. The levels of inorganic ions within the unplasticized cuticle are not sufficiently high to allow plasticization upon their removal. 4. No evidence for model (d) has been found; urea does not occur in the cuticle in detectable quantities. 5. Exact measurements of the intracuticular pH have not been achieved but straining experiments strongly suggest that a change in pH occurs within the cuticle on plasticization. This pH change is probably large enough to account for the increased extensibility shown by plasticized cuticle.