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[Animal study on radioactive antigenic fractions isolated from V.cholerae. I. The Ch 1 + 2 fraction].

The Ch 1 + 2 fraction has been marked by means of culture of Vibrio cholerae Ogawa HK1 on a synthetic medium containing leucine H3. The antigen distribution has been then studied before and after vaccination with the same non-marked antigen in normal and axenic mice, at the same time by the demonstration of radioactivity and radioimmunofluorescence in intestine, spleen, liver, kidney and thymus. Whichever the administration route, intestine and spleen are first stimulated, then more intensively with the second injection or ingestion. When administrated per os the fraction crosses the intestinal barrier and is fixed on the main lymphoid organs: intestine, spleen, thymus. After ingestion or injection into axenic mice, spleen is the first organ stimulated.

Animals↗

[Studies on serum protein fractions of patients with uterine cervical cancer undergoing radiotherapy: relationship between changes in serum protein fractions and prognosis].

The levels of 23 protein components of the sera of 84 patients with uterine cervical cancer undergoing radiotherapy were determined by a single radial immunodiffusion method, before radiation therapy, after whole pelvic irradiation, and after intracavitary irradiation using a remote after roading system (RALS). We examined the correlations between changes in serum protein fractions and the prognosis of the patients. The patients with uterine cervical cancer were treated with combined external irradiation of 60Co gamma-rays or 10 MV X-rays, and RALS therapy. The levels of the same protein components were also measured in 21 normal adult women as a control. All patients were observed between 4 years and 8 years after radiation therapy. In the pretreatment sera obtained from patients with uterine cervical cancer, the concentrations of prealbumin (Prealb), alpha 2HS glycoprotein (alpha 2 HS), alpha 2-plasmin inhibitor (alpha 2PI), transferrin (Tf), plasminogen (Pmg), albumin (Alb), IgM and hemopexin (Hx) were significantly lower than those normal controls. However the serum concentrations of: alpha 1-antichymotrypsin (alpha 1 X), haptoglobin (Hp), C9, fibrinogen (Fib), ceruloplasmin (Cp), alpha 1-acid glycoprotein (alpha 1AG), alpha 1-antitrypsin (alpha 1AT) and C4 were elevated. At the completion of whole pelvic irradiation and RALS therapy, the Hp, C4, and Fib levels were significantly lower than those before radiation therapy, whereas Prealb, alpha 2HS and alpha 2PI were elevated. In patients who had lived between 4 years and 8 years after radiation therapy, the Cp, alpha 1 AG, Hp and C9 levels measured before radiation therapy were reduced significantly, while Tf was elevated compared with patients who died within 4 years. In those who had lived more than 4 years, the alpha 1 AT, Hp, alpha 1X, Cp and C9 levels measured after whole pelvic irradiation were reduced significantly; while the C4 level was elevated. In cases of uterine cervical cancer followed for a period of 4 to 8 years after radiation therapy, multiple regression analysis was used to determine whether increased concentrations of serum protein fractions were associated with good prognosis for the original disease. Tf, Pmg, and alpha 1AT before radiation therapy were positively correlated with survival, whereas AT III, Cp, C1Inh, IgA, alpha 1 AG and C9 showed negative correlations. After whole pelvic irradiation,Pmg, C4 Prealb, Alb,alpha 2M and Hp were found to be positively associated with survival, whereas Tf, alpha 2PI, AT III, alpha 1 AT,C1Inh, C9 and IgA were negative factors.

Adult↗

[Studies on serum protein fractions of patients with maxillary sinus cancer undergoing a combination of radiotherapy and chemotherapy: II. Relationship between changes in serum protein fractions and prognosis].

We examined the correlations between changes in serum protein fractions and the prognosis of the patients. The levels of 21 protein components of the sera of 36 patients with maxillary sinus cancer were determined by a single radial immunodiffusion method before and after radiation therapy. The patients with maxillary sinus cancer were treated with combined intra-arterial infusion of bleomycin and external irradiation of 60 Co gamma-rays, and were concurrently treated with 5-fluorouracil at 200 mg/day p.o. The levels of the same protein components were also measured in 34 normal adult as a control. All patients were observed 5 years and 12 years after radiation therapy. In patients who had survived at least 5 years after radiation therapy, the Alb, Tf, Hx, IgG and IgM levels measured before radiation therapy were elevated significantly compared with those who had died within 5 years. In those who had survived at least 5 years, the Alb, Tf, Hx, IgG, IgM, IgA and I alpha I levels measured after radiation therapy were elevated significantly compared with those who had died within 5 years, and AT III was reduced. In cases of maxillary sinus cancer following a period of 5 to 12 years after radiation therapy, multiple regression analysis was used to determine whether increased concentrations of serum protein fractions were associated with good prognosis for the original disease, alpha 2HS. IgM, HX, alpha 1AT and alpha 1X before radiation therapy were positively correlated with survival, whereas AT III, Pmg, Cp, IgA, and alpha 1AG showed negative correlations. After radiation therapy, Pmg, Hx, Cp, Cl inh and Fib were found to be positive factors of survival rate, whereas alpha 2M, alpha 2Pl, I alpha 1, IgA, alpha 1AG and C3 were negative factors.

Adult↗

[T.D.F. (time-dose-fractioned irradiation) and tolerance to low flow and low fractioned irradiation (author's transl)].

1. The factor (T.D.F.) defined by ORTON and ELLIS for regularly distributed discontinuous irrdiation may be dissociated from Ellis' equation. The essential fact is that, in principle, the T.D.F. is given as 100 for all techniques which are associated with full tolerance or, if desired, exact saturation of the normal supporting tissue. 2. From this standpoint, all techniques in which T.D.F. = 100 have the same effectiveness as the N.S.D., i.e. 1,800 Rads given at a flow of approximately 10 Rads per minute. A TD.F. greater or less than 100 should be considered as evaluating the effective dose as a percentage of the N.S.D. The total dose administered effectively as a percentage of N.S.D., Dt/18 represents by contrast the actual dose. 3. With discontinuous treatment of 50 or 100 Rads/minute, the ratio effective dose over actual dose = T.D.F. 18/Dt represents the coefficient of reduction in effectiveness due to fractioning. Crf (the T.D.F. of which is given in the tables of Orton and Ellis). In the case of continuous uninterrupted treatment, the coefficient of reduction of effectiveness by protraction Crp is calculated using Orton's equation. With treatment given on an interrupted basis (split) the reduction in effectiveness Crs is calculated on the basis of the appendix ratio of Orton and Ellis. 4. In low flow rate, low fractioned treatment, in interrupted sections, the overall coefficient of reduction of effectiveness equals the product of the three mentioned above: Crg = Crf-Crp-Crs. 5. Dissociation of the T.D.F. factors from Ellis' equation makes it possible to generalise its principle and to extend it to all normal tissue (kidney, lung, intestine, marrow), the T.D.F. of which represents that state in which radiolesions are maximally compatible with reversibility, in the immediate or in the shortest possible time. It would be theoretically possible, using a suitable experimental technique, to develop, for each of these particularly senstive organs, tables analogous to those provided by ORTON and ELLIS for supporting tissue in conditions which seem acceptable to many.

Cobalt Radioisotopes↗

Tissue-culture cell fractionation. Fractionation of membranes from tissue-culture cells homogenized by glycerol-induced lysis.

1. The disruption of various types of tissue-culture cells by (a) incubation in solutions of 1.2 M-glycerol and (b) transfer of the glycerol-loaded cells to relatively hypo-osmotic solutions of 0.25 M-sucrose was studied. 2. Bivalent cations (2mM-Mg2+) were generally included to preserve the nuclei, but some cells (polyoma-virus-transformed baby-hamster kidney cells) failed to be disrupted adequately under these conditions. 3. Other cells (mouse-embryo fibroblasts) required additional gentle Dounce homogenization to effect complete cell breakage. 4. Purification of the whole homogenate was carried out by a combination of differential centrifugation and sedimentation or flotation through sucrose gradients. 5. Enzyme analysis showed that plasma-membrane, endoplasmic-reticulum and mitochondrial fractions were obtained in good yield and purity.

Animals↗

Tissue-culture cell fractionation. Fractionation of cellular membranes from 125I/lactoperoxidase-labelled Lettrée cells homogenized by bicarbonate-induced lysis: resolution of membranes by zonal centrifugation and in sucrose and metrizamide gradients.

1. Lettrée cells were grown intraperitoneally in MF-1 mice and labelled extrinsically by the 125I/lactoperoxidase technique. 2. The cells were swollen in 1 mM-NaHCO3 and disrupted in a Dounce homogenizer. 3. Crude fractions of endoplasmic reticulum, plasma membrane and mitochondria were separated from a post-nuclear supernatant by sedimentation-rate gradient centrifugation in a BXIV zonal rotor. 4. Further resolution of these membranes was carried out in isopycnic sucrose gradients. 5. Bands of material from the latter were subfractionated in gradients of metrizamide. Some very pure subfractions of plasma membrane and endoplasmic reticulum were obtained. In addition, one subfraction containing 125I and NADPH-cytochrome c reductase but no Na++K+-stimulated adenosine triphosphatase and another containing these two enzymes but no 125I were resolved.

Animals↗

The calcium accumulation in a microsomal fraction from porcine coronary artery smooth muscle. A study of the heterogeneity of the fraction.

1. Microsomes prepared from the combined media and intima of pig coronary artery, take up Ca in an ATP-dependent way. This uptake is stimulated by oxalate. 2. Conditions have been determined to optimize the preparation of the microsomes in terms of their Ca accumulation activity. Careful homogenization of the tissue mince in 0.25 M sucrose by means of a Potter-Elvehjem homogenizer gives microsomal preparations with the highest specific activity for Ca accumulation. 3. Arguments are presented to support the hypothesis that, even in the absence of oxalate, Ca accumulation occurs into the lumen of the vesicles, and that these vesicles have a low Ca permeability. 4. Density gradient analysis shows that the microsomal fraction prepared from pig coronary artery media and intima is composed of vesicles that are heterogeneous in enzymatic composition. 5. Adenylate cyclase appears to be a predominantly plasma membrane-bound enzyme. Rotenone-insensitive NADH-cytochrome c reductase and choline phosphotransferase, two putative markers for internal membranes, give distinct banding patterns on on isopycnic centrifugation, indicating different intracellular localization. 6. There is a difference between the density gradient distribution pattern of Ca uptake measured in the presence or absence of oxalate. The latter coincides more closely with plasma membrane markers. The former resembles more the distribution of rotenone-insensitive NADH-cytochrome c reductase.

Animals↗

Fractionation of membrane proteins by temperature-induced phase separation in Triton X-114. Application to subcellular fractions of the adrenal medulla.

After solubilization with the detergent Triton X-114, membrane proteins may be separated into three groups: if the membrane is sufficiently lipid-rich, one family of hydrophobic constituents separates spontaneously at low temperature; warming at 30 degrees C leads to separation of a detergent-rich phase and an aqueous phase. Using the chromaffin-granule membrane as a model, we found that many intrinsic membrane glycoproteins are found in the latter phase, probably maintained in solution by adherent detergent. They precipitate, however, when this is removed by dialysis, leaving in solution those truly hydrophilic proteins that were originally adhering to the membranes. We have used this method with mitochondria, and with Golgi- and rough-endoplasmic-reticulum-enriched microsomal fractions: it has proved to be a rapid and convenient method for effecting a partial separation of proteins from a variety of different membranes.

Adenosine Triphosphatases↗

Electron microscope examination of subcellular fractions. 3. Quantitative analysis of the microsomal fraction isolated from rat liver.

Rat liver microsomes and microsomal subfractions isolated by density equilibration were submitted to a quantitative morphological and biochemical analysis. The total area of the endoplasmic reticulum was estimated at 7.3 m(2) per g of liver. The microsome fraction contained 2.8 mg of phospholipids and 6.7 mg of proteins per m(2) of membrane area. After correction for ribosomal and intracisternal proteins, the latter value was lowered to 4.7 mg of membrane protein per m(2). More than half of the microsomal vesicles carried ribosomes. After density equilibration of the microsomes, the distribution pattern of ribosomes followed closely that of RNA. The ribosome load of the microsomal vesicles increased steadily along the density gradient, indicating the existence of a continuous spectrum of microsomal entities ranging from entirely ribosome-free vesicles to vesicles heavily coated with ribosomes.

Animals↗

[Studies on bradykinin-binding cell fractions. 1. Characterization of kininase activity of the microsomal and membrane fraction from the rat uterus].

In the membrane fraction of rat uterus, kinin-destroying activity was found and characterized as kininase II by means of several kininase inhibitors. It could be shown that sudies of bradykinin-receptor interactions requires the use of kininase inhibitors like phenanthroline or the use of a stable bradykinin analogue like [8-erythro-alpha-amino-beta-phenylbutyric acid]-bradykinin.

Angiotensin-Converting Enzyme Inhibitors↗

[Fractionation of the nucleotides of the acid-soluble liver fraction of rats].

A method for separation of rat liver acid-soluble nucleotides was developed including ion exchange polyethyleneimine cellulose chromatography, followed by rechromatography of the separate fractions on Dowex 1 and Aminex MS resins. It is simple, reproducible and does not require expensive reagents and devices. The sensitivity of the method in respect to orotate is 100 pM in a sample. Data on the content of liver basic 5'-ribonucleotides and their derivatives were obtained by the proposed method.

Animals↗

T cell responses to fractionated Mycobacterium leprae antigens in leprosy. The lepromatous nonresponder defect can be overcome in vitro by stimulation with fractionated M. leprae components.

Protective immunity against Mycobacterium leprae is dependent on M. leprae-reactive T lymphocytes. M. lepare-directed T cell reactivity is high in the localized tuberculoid form of leprosy but specifically absent in the disseminated lepromatous type of the disease. Two important questions that are relevant for the understanding of the immune response in leprosy as well as for the design of rational immunoprophylaxis and -therapy strategies are: (a) what are the antigens that trigger T cell responses in tuberculoid patients and thus protect these individuals from developing lepromatous leprosy and (b) is it possible to restore T cell responsiveness to M. leprae in lepromatous patients by rechallenging the immune system with selected antigens that will trigger help but not suppression? We have addressed these question by directly probing the peripheral T cell repertoire of 10 tuberculoid and 18 lepromatous patients with large numbers of different M. leprae and BCG antigenic components that had been separated on the basis of their relative molecular mass (Mr) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electroblotted onto nitrocellulose. This technique allows the identification of T cell-stimulating antigens independent of the expression of B cell epitopes by these antigens. So far T cell epitopes have only been mapped on M. leprae proteins that had previously been defined by antibodies. Our results show that: (a) tuberculoid patients' T cells responded preferentially to M. leprae and BCG antigens in the lower (i.e. less than 70 kDa) Mr range with a peak in the 10-25 kDa range; (b) 6 out of 18 lepromatous patients that did not respond to whole M. leprae responded strongly to isolated M. leprae components; antigens in the lower Mr. range were recognized by five out of these six patients and thus commonly seen by both tuberculoid and lepromatous patients' T cells; however, antigens in the higher Mr range, in particular greater than 150 kDa, were only recognized by lepromatous patients' T lymphocytes; (c) furthermore, the T and B cell repertoires in leprosy patients are skewed towards different antigenic fractions.

Antibodies, Bacterial↗

Continuous assessment of perfusion by tagging including volume and water extraction (CAPTIVE): a steady-state contrast agent technique for measuring blood flow, relative blood volume fraction, and the water extraction fraction.

A new technique, CAPTIVE, that is a synthesis of arterial spin labeling (ASL) blood flow and steady-state susceptibility contrast relative blood volume imaging is described. Using a single injection of a novel, long half-life intravascular magnetopharmaceutical with a high tissue:blood susceptibility difference (deltachi) to deltaR1 ratio, changes in tissue transverse relaxivity (deltaR2 or deltaR2*) that arise from changes in blood volume were measured, while preserving the ability to measure blood flow using traditional T1-based ASL techniques. This modification permits the continuous measurement of both blood flow and blood volume. Also, because the contrast agent can be used to remove the signal from intravascular spins, it is possible to measure the first-pass water extraction fraction. Contrast-to-noise is easily traded off with repetition rate, allowing the use of non-EPI scanners and more flexible imaging paradigms. The basic theory of these measurements, several experimental scenarios, and validating results are presented. Specifically, the PaCO2-reactivity of microvascular and total relative cerebral blood volume (rCBV), cerebral blood flow (CBF), and the water extraction-flow product (EF) in rats with the new contrast agent MPEG-PL-DyDTPA is measured, and the values are concordant with those of previous literature. As an example of one possible application, continuous flow and volume measurements during transient focal ischemia are presented. It is believed that CAPTIVE imaging will yield a more complete picture of the hemodynamic state of an organ, and has further application for understanding the origins of the BOLD effect.

Animals↗

The pharmacological effect of fractions obtained by smoking cannabis through a water-pipe. II. A second fractionation step.

The catatonic activity, prolongation of phenobarbital sleeping-time, convulsant action and disruption of nest-building activity was assessed in mice subjected to 4 cannabis pyrolysis products and their tobacco analogues. All but one of the cannabis fractions prolonged the pentobarbital sleeping-time and disrupted the nest-building activity of mice in a way not related to their content in the main cannabinoids. Nest-building activity seems to be the most valid assay we have used so far.

Animals↗

Regional myocardial wall thickening and global ejection fraction in patients with low angiographic left ventricular ejection fraction assessed by visual and quantitative resting ECG-gated 99mTc-tetrofosmin single-photon emission tomography and magnetic resonance imaging.

We investigated the use of visual and quantitative technetium 99m tetrofosmin ECG-gated single-photon emission tomography (SPET) for the assessment of regional myocardial wall thickening (WT) and left ventricular (LV) ejection fraction (EF) in comparison with gated magnetic resonance imaging (MRI) in patients with a low angiographic LVEF. Gated SPET using 99mTc-labelled flow tracers offers potential for simultaneous assessment of myocardial perfusion and LV function. Few data are available on the use of visual and quantitative gated SPET in patients with low LVEF. In this study 21 patients with low angiographic LVEF (mean 37%+/-5%) were studied. Resting gated 99mTc-tetrofosmin SPET and gated MRI were performed within 48 h. WT was assessed by visual interpretation (five point score) and quantitative analysis based on count increase. There was good agreement for EF measurements by MRI and gated SPET (mean EF: 33%+/-12% vs 35%+/-11%, r = 0.86, P<0.001). Areas under receiver operator characteristic curves (AUC) for differentiation between MRI WT score points ranged from 0.60 to 0.66 for visual SPET WT analysis, from 0.59 to 0.71 for delta count increase values and from 0.46 to 0.60 for % WT, indicating substantial overlap between WT categories. Absolute agreement for visual WT between MRI and gated SPET ranged from 25% to 57% (kappa 0.03-0.25) depending on tracer uptake, and was limited in areas with moderate to severe perfusion defects (kappa 0.03-0.13). It is concluded that gated SPET provided reliable estimates of regional WT and global function in patients with low angiographic LVEF.

Coronary Angiography↗

Fractional calculus in biomechanics: a 3D viscoelastic model using regularized fractional derivative kernels with application to the human calcaneal fat pad.

A viscoelastic model of the K-BKZ (Kaye, Technical Report 134, College of Aeronautics, Cranfield 1962; Bernstein et al., Trans Soc Rheol 7: 391-410, 1963) type is developed for isotropic biological tissues and applied to the fat pad of the human heel. To facilitate this pursuit, a class of elastic solids is introduced through a novel strain-energy function whose elements possess strong ellipticity, and therefore lead to stable material models. This elastic potential - via the K-BKZ hypothesis - also produces the tensorial structure of the viscoelastic model. Candidate sets of functions are proposed for the elastic and viscoelastic material functions present in the model, including two functions whose origins lie in the fractional calculus. The Akaike information criterion is used to perform multi-model inference, enabling an objective selection to be made as to the best material function from within a candidate set.

Adipose Tissue↗

Comparison of the continuously calculated fractional splanchnic extraction of insulin with its fractional disappearance using a new double-tracer technique.

These studies were designed to calculate the fractional disappearance rate (FDR) and splanchnic extraction of insulin in response to an exogenous (intraperitoneal) input of insulin. A double-tracer technique using insulin tritiated on both the A1 and B1 positions was introduced for the measurement of hepatic extraction. The A1 tracer, not previously characterized in vivo, was compared in terms of its kinetics with H3-B1-insulin and unlabeled insulin. The metabolic clearance rates (MCR) of the three insulins were identical, as were the decay curves of the two tracers. To measure splanchnic insulin extraction, one tracer was infused systemically to evaluate the FDR of insulin, and the second was infused into the splanchnic circulation (superior mesenteric artery) and its peripheral appearance was calculated. Splanchnic extraction was determined from the difference between this rate of appearance and the rate of infusion of the mesenteric tracer. After intraperitoneal insulin injection, insulin levels increased to peaks of 549 +/- 93 microU/mL (portal vein) and 473 +/- 99 microU/mL (inferior vena cava) and decreased to basal levels over 3 hours. The FDR decreased from 0.295 +/- 0.051 min-1 to 0.125 +/- 0.026 min-1, and splanchnic extraction decreased from 0.534 +/- 0.06 to 0.232 +/- 0.088. The latter returned to near-basal values more rapidly than did the FDR. In conclusion, the kinetics of insulin both in and out of the steady state have been shown to be nonlinear through physiological insulin concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Spheroid control of malignant glioma cell lines after fractionated irradiation: relation to the surviving fractions at 2 Gy and colony forming efficiencies in a soft agar clonogenic assay.

Spheroid control doses (SCD50) were determined for ten human glioma lines after fractionated irradiation under oxic conditions. In addition, SF2 values and colony forming efficiencies (CFE) were measured in a soft agarose clonogenic assay. A significant relationship existed between the SCD50 values and the SF2-CFE data pairs (p = 0.01) but the SCD50 values were higher than expected from the SF2 and CFE values. This comparison shows the influence of environmental factors (different in both model systems) on reproductive tumour cell death after irradiation.

Cell Aggregation↗