Correlation between patient weight and defects in DNA mismatch repair: is this the link between an increased risk of previous cancer in thinner women with endometrial cancer?

The objective is to determine the relationship between obesity and defects in DNA mismatch repair (MMR) in women with endometrial cancer and to establish whether our previous finding of a higher rate of previous malignancy in thinner women with endometrial cancer is related to these factors. Specimens from 109 patients with primary uterine cancer were used to create a tissue microarray, which was stained with antibodies against MMR genes MLH1, MSH2, MSH6, and PMS2. Genotyping of normal and tumor tissues for microsatellite instability (MSI) was performed. Patients were stratified by body mass index (BMI) and correlated with a history of previous malignancy and defects in MMR. The average BMI of the overall population was 33 kg/m(2). Defective MMR was seen in 22% of tumors. The mean BMI in patients with tumors with MSI was 30.5, compared with 33.8 in microsatellite stable (MSS) tumors (P= 0.06); MSS tumors were more commonly seen in patients with a BMI more than 40 (25% vs 5% in patients with tumors with MSI, P= 0.07). Prior to their diagnosis of endometrial cancer, 16/109 (15%) patients reported having a prior malignancy, 11 (69%) had breast cancer, and 1 had colorectal cancer. Patients with tumors with MSI had previous cancer in 17% of cases, compared with 14% of patients with MSS tumors (P= 0.75). Our previous finding of an increased rate of prior malignancy in thinner patients with endometrial cancer does not appear to be due to alterations in MMR, and hereditary nonpolyposis colorectal cancer-associated cancers are rarely the prior malignancy.

Mechanism of the fluorescent light induced suppression of Curly phenotype in Drosophila melanogaster.

A dominant mutation Curly (Cy), frequently used as a marker on the second chromosome in Drosophila melanogaster, was previously shown to be suppressed by several factors, including larval crowding, low temperature, and fluorescent light. While the first two factors affect this mutation only partially, fluorescent tube exposed flies exhibit an almost completely suppressed (wild type) phenotype. This suppressive effect is the result of a combination of the electric field and light, both factors being produced by common fluorescent tubes. In this study, experiments were carried out to clarify the basic mechanism of this unique phenomenon. Two fluorescent tube sensitive stages of Drosophila development were found in the second half of embryonic development and first half of the pupal stage. Riboflavin, which is administered to Drosophila larvae with yeast, and decomposed by light, seems to play a key role in this phenomenon. In a medium lacking riboflavin caused by light exposure, Cy expression is inhibited by the action of electric field. Positive results of experiments with lithium ions, which block the opening of Ca(2+) channels, support the hypothesis that electromagnetic fields may alter ion currents during ontogenic development of Drosophila, and thus influence, expression of the Cy gene. Also, fluorescent light induces an overexpression of a specific protein in the imaginal wing disc of Cy pupae.

Inheritance of a temperature-modified phenotype of the short antennae (sa) mutation in a moth, Ephestia kuehniella (Lepidoptera: Pyralidae).

The autosomal recessive mutation short antennae (sa) causes considerable shortening of antennae in male and female Mediterranean flour moths (Ephestia kuehniella Zeller). However, the sa phenotype can be suppressed by several physical factors, making sa moths indistinguishable from wild-type moths (sa(WT)). This can be done by subjecting larva and pupa to a higher temperature (25 degrees C), to lithium ions, or to an alternate electric field. The first half of pupal development was found to be the sensitive period for the sa(WT) phenotype. The sa(WT) phenotype is stable and cannot be reverted to the original sa type by physical or chemical factors. The sa(WT) phenotype is transmitted to future generations. When crossed with typical sa moths, the sa(WT) phenotype is inherited either as a dominant character if carried by males or a semidominant character if carried by females. We compared proteins of the ejaculate, accessory gland secretions, and spermatophore in sa, sa(WT), and wild-type males and found considerable differences between sperm proteins of sa(WT), sa, and wild-type males. The sa(WT) phenotype influences the mating success of males: sa(WT) males mated successfully with any females, whereas typical sa males were less successful in mating and then mainly with females of the same phenotype.

Differential effects of selective vagotomy and tropisetron in aminoprivic feeding.

Both total subdiaphragmatic vagotomy (TVAGX) and serotonin(3) receptor blockade with tropisetron or ondansetron attenuate amino acid-imbalanced diet (Imb) anorexia. Total vagotomy is less effective than tropisetron in reducing Imb-induced anorexia and also blunts the tropisetron effect. With the use of electrocautery at the subdiaphragmatic level of the vagus, we severed the ventral and dorsal trunks as well as the hepatic, ventral gastric, dorsal gastric, celiac, and accessory celiac branches separately or in combination to determine which vagal branches or associated structures may be involved in these responses. Rats were prefed a low-protein diet. On the first experimental day, tropisetron or saline was given intraperitoneally 1 h before presentation of Imb. Cuts including the ventral branch, i.e., TVAGX, ventral vagotomy (above the hepatic branch), and hepatic + gastric vagotomies (but not hepatic branch cuts alone) caused the highest (P < 0.05) Imb intake on day 1 with or without tropisetron. The responses to tropisetron were not affected significantly. On days 2-8, groups having vagotomies that included the hepatic branch recovered faster than sham-treated animals. Because the hepatic and gastric branches together account for most of the vagal innervation to the proximal duodenum, this area may be important in the initial responses, whereas structures served by the hepatic branch alone apparently act in the later adaptation to Imb.

[Chemical contamination of the cervical mucus in cows in relation to pregnancy and age factors]. / Kontaminace cervikálního hlenu krav chemickými prvky ve vztahu ke koncepci a veku.

Applying the method of absorption atom spectrometry (AAS), the contamination of cervical mucus by chemical elements (Cd, Pb, Hg, Cr, Cu, Zn) was demonstrated in the oestrus period of cows in different ecological agricultural regions of the North Moravian region. The results of observation revealed only a statistically significant difference (P less than 0.05) in Cd contents in the test groups; test group mean = 0.015 micrograms.g-1 Cd, control group mean = 0.006 micrograms.g-1. Cr findings in cervical mucus are of priority importance, the same applies to Cu findings. Zinc was found to be an element influencing negatively the conception of cows. The Zn values in cervical mucus of nonpregnant cows were demonstrated to be significantly higher (P less than 0.01) (conception--group = 0.841 micrograms.g-1, conception + group = 0.219 micrograms.g-1 Zn. So called sum of chemical elements: Cd + Pb + Hg + Cr + Cu + Zn was proposed and evaluated as a picture of the total contamination of cervical mucus. This characteristic was also influenced by the Zn findings in the group of pregnant and nonpregnant cows. Zn: Cd antagonism in cervical secretions of barren and pregnant cows was statistically highly significant (P less than 0.01). Chemical elements in cervical mucus were determined for the first time in a digested sample of cervical secretion. The correlation coefficients used for the cows (n = 99) from a contaminated region showed that the content of chemical elements in cervical secretion was not influenced by the age of cows. The content of chemical elements in cervical secretion was not increasing with the age.

[Levels of toxic elements--Cd, Pb, Hg, Cr, Cu, Zn--in the blood and placenta of cows during parturition and in newborn calves]. / Obsah toxických prvku--Cd, Pb, Hg, Cr, Cu, Zn--v krvi a placente krav v dobe porodu a u narozenych telat.

It was demonstrated that mother's blood and the blood of new-born calves were contaminated by toxic elements in exposed and non-exposed area. The average Cd and Zn levels differed at high statistical significance (P less than 0.01) in the mothers blood from non-exposed regions in comparison with the average Cd and Zn levels from exposed region. The average residues of toxic elements in breeding cows placenta from the exposed and non-exposed regions were not statistically different. The average Zn content in new-born calves from non-exposed regions differ highly statistically significantly in comparison with the average Zn content in the blood of new-born calves from heifers of the exposed region. The transplacental ratio (TPx) of a toxic element in cow placenta during parturition was expressed from the average ratio of toxic element content in mother's blood: toxic element content in placenta: the toxic element content in blood of newborn calf, while the content of toxic element in mother's blood during parturition was expressed by a value equal to one. TPx in parturition period was expressed by mathematical formula TPx = 1 : Xp : Xk, where Xp = toxic element content in placenta, Xk = content of the toxic element in blood of new-born calf. TPPb, Hg, Cr, Cu, Zn values were not statistically different between the groups of breeding cows from exposed and non-exposed regions. TPCd in the group comprising 14 first-calves from the exposed region (TPCd = 1:0.89:2.59 in comparison with TPCd of six cows from non-exposed region, where TPCd = 1:0.29: 0.70;, differed statistically highly significantly (P less than .01). High statistical differences (P, less than 01) TPCd between these groups were explicitly affected highly statistically significantly (P less than .01) by different average Cd content in the blood of fourteen first-calves, compared with the average Cd content in blood of six cows from non-exposed region, in which the Cd value in blood during parturition was higher by 10(-1).

[Non-enzymatic browning reaction of histamine and D-glucose and its use in the manufacture of fish products]. / Reakce neenzymového hnednutí mezi histaminem a D-glukózou a moznosti jejího vyuzití pri výrobe potravin z ryb.

The reaction between histamine and D-glucose was studied in model systems at different pH values and at histamine concentration of 0.002 M and D-glucose concentration of 0.01 M. Further, the histamine--D-glucose reaction was studied at the physiological pH value of fish muscle, i. e. 6.6 (histamine concentration 0.005 M, D-glucose concentration 0.122 M). During this reaction the original histamine level decreased by 70%. The measurement of reaction kinetics demonstrated that a first-order reaction was involved with a velocity constant of 5.75 . 10(-2).h-1. The summarized formula of the produced brown pigment--(C12H15O6N)n was determined by the elementary analysis of the products of the reaction between histamine and D-glucose. Three unknown substances were found in the reaction mixture by means of thin-layer chromatography. On the basis of the measurement of the mass spectrum, one of these substances was identified as 5-methyl-2-furancarboxylic acid. The effect of metals (Sn, Fe) on the mentioned reaction manifested itself as an increase in reaction velocity in the case of an addition of metallic iron--velocity constant k = 9.6 . 10(-2).h-1. After the addition of D-glucose, the histamine level in histamine-containing mackerel muscle decreased by 24--65% down from the original amount at temperatures 100--130 degrees C. Further, a technological experiment with the preservation of histamine-containing mackerel muscle was performed, 6% of D-glucose being added to the muscle. After 217 days of the storage of cans at room temperature the preserved matter lost 50% of its histamine.

[Physical and chemical effect of reducing histamine levels in the meat of mackerel-type fish and its application in the manufacture of fish products]. / Fyzikální a chemické vlivy na snízení hladiny histaminu v mase makrelovitých ryb a moznosti jejich aplikace pri výrobe potravin z ryb.

The processing of fish (mackerels) with the potential ability of producing histamine leads to the production of hygienically unsafe food. Elimination of histamine production in fish food in the process of the technological production procedure was studied. The stability of histamine in model systems and in mackerel muscle was studied as influenced by temperature. Histamine was demonstrated to be thermally stable. Efforts to use the possibility of deamination reaction of histamine decomposition by means of plant and animal diaminooxidase failed, nor is it possible to recommend the use of the reaction between histamine and sodium nitrite, which was tested as a procedure of the degradation of histamine in the muscle of mackerels. The reduction of histamine content was negligible and the nutritive value of fish muscle decreased owing to the breakdown of amino acids.

[The occurrence of cadmium in some types of food]. / Sledování výskytu kadmia v nekterých druzích potravin.

An examination of 732 samples of foods of animal and vegetable origin revealed that 95% sea fish products, 94% samples of sea and fresh-water fish, 69.9% samples of foods of vegetable origin and 32.9% samples of foods of animal origin -- tinned beefand pork -- pâtés and spreads -- did not comply with the requirements of the standard on contaminants in foods for cadmium content. Together with the investigation of cadmium content in foods the applied method of atomic absorption spectrophotometry was tested, from the point of interferences during establishing the actual cadmium content; at the same time, this study concerned cadmium losses during the process of mineralization of the biologic material samples. It was concluded that the measured cadmium values were affected by the presence of a higher content of sodium chloride in the samples. The re-gained yield of cadmium by the used method of mineralization is 85%.

[Arsenic contamination in imported sea fish and fish products made from them]. / Kontaminace arzénem u dovázených morskáych ryb a výrobku z nich

The rate of arsenic contamination in sea-fish is, in comparison with freshwater fish, relatively high. An investigation of five kinds of sea-fishes--of mackerel, herring, cod, tunny, and plaice--that are most frequently put on the market showed that a permitted value up to 1 mg As per 1 kg of fish meat was found only in 24.0% of mackerel, 9.5% of herring, 33.4% of cod, 57.0% of plaice and 0.0% of tunny. Further investigation of dressed fish--of fillets--revealed that 15.8% of herring fillets and 0.0% of cod fillets met the permitted value. The values of a majority of studied sea-fish samples ranged from 1 to 2 mg As per 1 kg: 52% of mackerel, 63.5% of herring, 66.6% of cod, 43% of tunny, 28% of plaice. It is necessary to revalue the permitted values of arsenic content in sea-fish and in products made from their meat and to defend the upper limits of the permitted arsenic value, which will require the purposeful organization of effective laboratory tests the results of which will directly influence an estimation of fish raw material and will provide the corresponding hygienic quality of fish and fish products.