The relationship of menopausal hot flushes to medical and reproductive experience

Information regarding the relationship of menopausal hot flushes to menstrual, reproductive and clinical events were obtained from women participating in a case-control study of breast cancer risk. Naturally menopausal women who reported the occurrence of menopausal hot flushes were compared with those without such complaints in an attempt to identify factors that might predict the occurrence of menopausal symptoms. Two-thirds of the women reported such symptoms. The symptomatic and asymptomatic groups did not differ in body weight, suggesting that extraglandular estrogen production in obese women does not protect against occurrence of menopausal symptoms. Neither past medical nor reproductive history were predictive of the occurrence of hot flushes. Women with hot flushes more commonly reported the occurrence of menstrual cycle variability and of long menstrual cycles during the 5 years before menopause. Since perimenopausal cycle variability probably reflects the irregular maturation of residual ovarian follicles accompanied by elevated gonadotropin concentrations, symptomatic women may have earlier activation of the neuroendocrine mechanism that has been associated with both pulsatile gonadotropin release and the hot flush.

Distribution of Iron in Sphaerotilus and the Associated Inhibition

The distribution of iron between the sheaths and the cells of iron-inhibited Sphaerotilus cultures was determined. The experiment was conducted with different soluble iron forms as inhibitors. The growth inhibition was found to be related to the iron sorbed by the cells rather than by the sheaths. At the 90% inhibition level, iron sorbed by the cells ranged from 13 to 15 mg/g of organism for all three inhibitors tested. For 50% inhibition, the iron sorbed by the cells ranged from 7 to 8 mg/g of organism. The iron sorbed by the sheaths varied widely, ranging from 23 to 118 mg/g of organism at the 90% inhibition level and from 11 to 61 mg/g at the 50% inhibition level. The degree of inhibition is closely related to the amount of iron sorbed by the cells, which in turn is a function of the type of iron compound or complex used. The solubility of the iron is a major consideration.

Radiation therapy of nasopharyngeal carcinoma

Carcinoma of the nasopharynx is one of the most frequent malignant tumors in the southern parts of China. A total of 3 263 cases treated with irradiation in the course of the thirty years since the Liberation have been analysed retrospectively. The 5-year survival rate has risen from 27.7 per cent for cases treated during 1955 to 1960 to 54 per cent for those treated in 1973. The technique of irradiation is described, emphasizing the importance of suitable techniques for the treatment of the cervical lymph nodes. The value of elective irradiation of cervical regions not involved clinically is elucidated. Finally, the causes of failure of treatment are discussed.

Comparative Study of Different Iron Compounds in Inhibition of Sphaerotilus Growth

The effectiveness of iron compounds on growth inhibition of Sphaerotilus species was compared. In this study, two strains of Sphaerotilus were tested with different iron concentrations in a synthetic sewage (S-medium) as formulated by Lackey and Wattie (Sewage Works J. 12 :669-684, 1940). For both strains, >80% inhibition of the maximum respiration rate was obtained by the following levels of soluble iron concentrations at pH 6.0: iron citrate, 20 mg/liter as Fe; iron cysteine, 5 mg/liter as Fe; and ferrous sulfate, 10 mg/liter as Fe. At a pH of 6.7 with iron citrate (20 mg/liter as Fe), inhibition of both strains was in excess of 50%. Insoluble iron compounds, such as iron hydroxides and ferrous carbonate, were found to be much less effective than the soluble iron compounds as inhibitors of these two strains. Aged iron hydroxide (500 mg/liter as Fe) produced a 70% inhibition in the maximum respiration rate while fresh iron hydroxide (52 mg/liter as Fe) and ferrous carbonate (500 mg/liter as Fe) produced a 20% inhibition. Chemical analyses of the iron-inhibited Sphaerotilus strains showed a close relationship between the inhibition of the organism's growth and the amount of iron sorbed by the organism.

Use of centrifugal disk atomizer to produce CdS films

The use of a centrifugal disk atomizer to produce chemically sprayed CdS films is described. The film growth rate has been found to depend on substrate temperature, solution concentration, and feed rate. The films grown on glass substrates have been studied by electron microscopy and x-ray diffraction. A fine-grained wurtzite structure has been obtained.

Light-scattering studies on bile acid salts II: pattern of self-association of sodium deoxycholate, sodium taurodeoxycholate, and sodium glycodeoxycholate in aqueous electrolyte solutions

The pattern of self-association of the bile salts sodium deoxycholate, sodium glycodeoxycholate, and sodium taurodeoxycholate was investigated in aqueous electrolyte solutions by the light-scattering technique. The turbidity of the bile salt solutions was obtained over the concentration range of 0-20 mg/ml at 25 degrees. These data were analyzed according to a monomer-micellar equilibrium model and a stepwise association model. Comparison of the light-scattering data with these models suggests that the monomer-micellar model may be inappropriate. Analysis of the data according to the stepwise association model suggests that the dihydroxy bile salts associate to form dimers, trimers, and tetramers in addition to a larger aggregate which varies in size depending on the degree of conjugation of the bile salt.

Atomic absorption spectrophotometry of free circulating platinum species in plasma derived from cis-dichlorodiammineplatinum(II)

We describe a method of analysis for free circulating platinum species derived from cis-dichlorodiammineplatinum(II) in blood plasma. Protein-bound and free platinum species were separated from each other by centrifugal ultrafiltration. Platinum in the ultrafiltrate was converted to a cationic complex by reaction with ethylenediamine, and the product was collected on paper impregnated with cation-exchange resin, where it could be stored indefinitely without loss. The platinum was eluted from the disk with 5 mol/liter hydrochloric acid, and an aliquot of this solution was then analyzed by flameless atomic absorption spectrophotometry. The overall analytical recovery of platinum was 80 +/- 2%. The minimum quantity of cis-dichlorodiammineplatinum detectable was 35 microgram/liter of plasma at the 99% confidence level. Detector response was linearly related to drug concentration in the range from 80 microgram to 290 mg of Pt per liter of plasma. Reaction variables were made optimal, so as to yield maximum sensitivity and reproducibility (+/- 2%) consistent with minimal sample transfers and manipulations.

Atomic absorption spectrophotometry of free circulating platinum species in plasma derived from cis-dichlorodiammineplatinum(II)

We describe a method of analysis for free circulating platinum species derived from cis-dichlorodiammineplatinum(II) in blood plasma. Protein-bound and free platinum species were separated from each other by centrifugal ultrafiltration. Platinum in the ultrafiltrate was converted to a cationic complex by reaction with ethylenediamine, and the product was collected on paper impregnated with cation-exchange resin, where it could be stored indefinitely without loss. The platinum was eluted from the disk with 5 mol/liter hydrochloric acid, and an aliquot of this solution was then analyzed by flameless atomic absorption spectrophotometry. The overall analytical recovery of platinum was 80 +/- 2%. The minimum quantity of cis-dichlorodiammineplatinum detectable was 35 microgram/liter of plasma at the 99% confidence level. Detector response was linearly related to drug concentration in the range from 80 microgram to 290 mg of Pt per liter of plasma. Reaction variables were made optimal, so as to yield maximum sensitivity and reproducibility (+/- 2%) consistent with minimal sample transfers and manipulations.

Solubilization of napthalene by sodium cholate and pattern of self-association of sodium cholate in 0.15 M sodium chloride

Naphthalene solubility was determined in aqueous 0.15 M NaCl containing sodium cholate in the 0-0.05 M concentration range at 25 +/- 0.1 degrees. Sodium cholate tends to self-associate in aqueous solutions. Most often, the association pattern has been described in terms of a monomer-micellar model in which it is assumed that no association occurs below the critical micelle concentration. By comparison of the experimental solubilization curve with curves calculated on the basis of the monomer-micellar model, it was shown that this model is inappropriate for the self-association pattern of sodium cholate. The solubility data were consistent with a model that assumes that sodium cholate associates to form dimers, trimers, and higher aggregates with an average aggregation number of 7.63. Model calculations suggest that naphthalene is solubilized by dimers and higher aggregates. Solubilization of naphthalene by trimers appears to be negligible.

Light-scattering studies on bile acid salts I: Pattern of self-association of sodium cholate, sodium glycocholate, and sodium taurocholate in aqueous electrolyte solutions

The pattern of association of the trihydroxy bile salts in aqueous electrolyte solutions was investigated utilizing the light-scattering technique. The turbidity of the bile salts sodium cholate, sodium taurocholate, and sodium glycocholate was determined over the concentration range of 0-25 mg/ml at 25 degrees. For sodium cholate, the concentration of the supporting electrolyte was varied from 0.15 to 0.5 M. For all bile salts in 0.15 M electrolyte, the turbidity was determined in sodium fluoride, sodium chloride, sodium bromide, and sodium iodide. Comparison of the light-scattering data with amonomer-micellar model showed that qualitative agreement was obtained; however, quantitative agreement could not be achieved. Further examination of the data showed that the light-scattering results were in good agreement with a model that includes dimers, trimers, and a higher aggregate containing approximately eight monomeric units.

Effects of radiation pasteurization on Samonella. 3. Radiation lethality and the frequency of mutation to antibiotic resistance

The radiation resistance (D, in megarads) of six strains of Salmonella irradiated at 4C in brain heart infusion suspension ranged from 0.042 for S. enteritidis to 0.084 for S. thompson. The resistance values were 0.048 for S. typhimurium, strain SR-11, 0.060 for S. typhimurium, strain RIA, and S. newport, and 0.078 for S. heidelberg. The mutation frequency to tetracycline resistance of S. typhimurium, strain SR-11, increased between 0 and 0.05 Mrad and declined thereafter with increasing radiation dose. After 0.5-Mrad exposure, the mutation frequency was essentially the same as in control populations. The mutation frequency to streptomycin resistance of S. typhimurium, strain SR-11, decreased at doses greater than 0.05 Mrad and increased only slightly for the more radiation-resistant serotypes, S. typhimurium, strain RIA, S. thompson, and S. heidelberg. The average mutation frequency of the four Salmonella cultures tested was essentially unchanged (less than 1 log difference) between 0.05 and 0.5 Mrad, while the difference in reduction in viable numbers was 5 logs or greater. The evidence presented indicates that with the proper choice of processing parameters, the application of radiation pasteurization could drastically reduce the possibility of transmission of Salmonella by poultry and thereby decrease the public health hazards associated with this microorganism.

Effects of radiation pasteurization on Salmonella. II. Influence of repeated radiation-growth cycles on virulence and resistance to radiation and antibiotics

Populations derived from Salmonella typhimurium surviving 1, 5, or 10 exposures to 0.5 Mrad did not show any increase in resistance to antibiotic discs containing 5 μg of tetracycline, 5 μg of chloromycetin, or 50 units of polymyxin. The frequency of resistance to 3 μg of tetracycline, 10 units of ampicillin, 120 μg of chloromycetin, or 30 μg of streptomycin per milliliter of agar, did not increase among progeny derived from either of two strains of S. typhimurium surviving 5–10 exposures to 0.5 Mrad. So, too, the virulence and radiation resistance of three strains of S. typhimurium exposed to radiation-growth cycling remained essentially unchanged or decreased.A mixture which originally contained 10 different serotypes of Salmonella was cycled at 0.23 Mrad. After 10 exposures the frequency of resistance of the progeny to ampicillin, chloromycetin, and streptomycin increased 87-, 55- and 13-fold respectively. The LD50 was essentially the same, but the radiation resistance (D value) increased from 0.053 Mrad in controls to 0.074 Mrad.The evidence presented seems to indicate that mutants are attained more readily from Salmonella cultures recycled at 0.25 Mrad or less than from those recycled at 0.5 Mrad. The pathogenicity of either one was usually essentially unchanged or reduced.

Effects of radiation pasteurization on Salmonella. I. Parameters affecting survival an recovery from chicken

Growth of Salmonella typhimurium, strain RIA, in minimal broth supplemented with methionine, produced a population of cells that was more sensitive to 60Co irradiation than were those grown in brain heart infusion. The resistance values (D) were 0.056 and 0.066 Mrad, respectively. D was not significantly different when the bacteria were irradiated at 4 °C on fresh or frozen-thawed germ-free chicken, or on conventional chicken sterilized by autoclaving, or by exposure to 2 Mrad of ionizing radiation. It was generally higher when the cells were irradiated in the original growth medium than on chicken. D of five different strains of S. typhimurium irradiated at 4 °C on autoclaved chicken varied from 0.052 to 0.068 Mrad. The greatest increase in resistance was produced by decreasing the temperature during irradiation. S. typhimurium, RIA, attained a D value of 0.293 Mrad at −80 °C. The effect of the recovery media on survival is equivocal. In some instances nutrient and minimal agar seemed to provide slightly better recovery of strains SR-11 and RIA. Enrichment of complex media with yeast extract did not increase recovery. The results indicate that of those parameters studied, the most significant effects on resistance were due to the temperature during irradiation.

Detoxification of Salmonella typhimurium lipopolysaccharide by ionizing radiation

The efficiency of ionizing radiation in detoxifying the lethal determinant(s) of the lipopolysaccharide (LPS) of Salmonella typhimurium, S. enteritidis, and Escherichia coli in aqueous solution and associated with heat-killed S. typhimurium cells in suspension decreased with doses above 1 Mrad. The 50% end point of inactivation was more than 7.0 Mrad for heat-killed salmonellae and 4.8, 4.5, and 1.0 Mrad for the LPS of S. typhimurium, S. enteritidis, and E. coli, respectively. After exposure to 20 Mrad, S. typhimurium LPS retained a small portion of its lethal properties although the ld(50) was much greater than 9.5 mg per 20-g mouse. However, at -184 C, no inactivation of the lethal determinant(s) occurred after exposure to as much as 20 Mrad. This demonstrated the significance of the indirect effect and the mobility and formation of free radicals. At 22 C, the optical density at 400 mmu increased and the pH decreased with increasing radiation dose, but no qualitative changes were observed in the infrared spectrum. No change was observed in the pyrogenicity of S. typhimurium LPS; a slight decrease in antigenicity was revealed when 6 days, but not when 1 day, elapsed between vaccination and challenge in the mouse protection test. The results were interpreted as evidence of the existence of two or more lethal and antigenic determinants. The differential effect of radiation on these properties and on the pyrogenic component(s) probably are indicative of separate functional sites for lethal, antigenic, and pyrogenic activities.

The chemistry of pyrrolic compounds. VI. Chlorins and related compounds

A novel bromination of porphyrins is described in which a compound of the chlorin class is produced. Evidence is presented in support of structure (VIa) for this compound. Mesochlorin and deuterochlorin have been prepared as model compounds during this investigation, and it has been shown by N.M.R. spectroscopy that both these chlorins have been reduced in either rings A or B and not in ring D as occurs in the chlorophylls a and b.