Distribution and clearance of polybrominated biphenyls in cows and calves

The distribution and clearance of polybrominated biphenyls were determined in two cows and a calf fed polybrominated biphenyls by boluses, by placental transport to a calf from a contaminated dam, and to another calf via milk from the contaminated dam. Feces were an important route of excretion of polybrominated biphenyls during exposure and the period when the contaminated feed was cleared from the digestive tract. Approximately 50% of single intraruminal doses of these hydrocarbons were cleared by 168 h. Free polybrominated biphenyls in urine could not be quantitated. However, 24% of carbon-14 from tetrachlorobiphenyl was recovered, suggesting that significant quantities of halogenated biphenyl may be excreted in urine. Milk was also an important excretion route with one cow excreting 23% of the polybrominated biphenyl dose in 168 days. Concentrations of polybrominated biphenyls in the fat of most tissues were similar, with higher concentrations in liver and lower in the nervous system. Gross or histopathologic lesions of tissues collected at necropsy could not be related specifically to polybrominated biphenyl toxicity.     

Limulus amebocyte lysate test in neonates

The limulus amebocyte lysate test for endotoxin was done on samples of blood from 22 well babies and 33 neonates in an intensive-care nursery. The objective was to determine whether falsely positive test results occurred in samples from newborn infants during acquisition of usual bowel flora. One neonate had a transiently positive limulus amebocyte lysate test; he had clinical signs of spesis, but no bacteremia could be documented. Unlike the nitroblue tetrazolium test, the limulus amebocyte lysate test does not appear to be regularly positive in neonates. The sensitivity of the test in detection of endotoxemia associated with gram-negative spesis in the neonate remains to be determined in a large prospective study.     

Results of a long-term wet storage demonstration test with intact and operational defective LWR fuel rods

28 spent fuel rods — 18 intact and 10 operational defective rods — were included in the storage test program. Within 7 years the spent fuel rods were inspected four times. To characterize the spent fuel rods the following methods were applied during pool inspections: visual inspection, profilometry, eddy current testing, and oxide thickness recording.Summarizing the results of the intermediate and of the final inspection it has to be concluded that — as predicted — no change exceeding the detection limit could be found either at the intact or at the operational defective fuel rods. These results must be regarded as conservative because handling of the different spent fuel rods during inspection provided additional and atypical loads — especially for the operational defective spent fuel — in comparison with the long term storage of complete fuel bundles.The results of this carefully documented demonstration test has shown agreement with the theoretical analysis and with the overall experience available from pool storage that wet spent LWR-fuel storage can be performed without any problems even for extended periods of time.     

Effect of the prolonged use of streptomycin as well as streptomycin in combination with tubazid on the bioelectrical activity of the brain in experimental tuberculosis]

The effect of streptomycin used alone and in combination with tubazid on the brain electric activity was studied in chronic experiments on rabbits with tuberculosis. The electrocorticographical investigations showed that the antibacterial treatment lowered the spontaneous electric activity and reactive capacity of the cortex. It was evident from a narrow amplitude of the main rythm, coefficient and energy of synchronization on rythmic photostimulation and paroxysmal activity withing the theta range. With the account of the high therapeutic effect of the antibacterial treatment evident from minimum affection of the organs with tuberculosis, the above changes in the electrocorticogrammes should be attributed to the neurotropic effect of the drug and not to tuberculosis intoxication.     

Monocular elevator paresis, Argyll Robertson pupils and sarcoidosis

Platelet concentrates were shown to contain 18 to 38 mg/dl of a phthalate plasticizer (DEHP) which arose by migration from the vinyl plastic packs in which the platelets were prepared and stored. Transfusion of these platelets into six adult patients with leukemia resulted in peak blood plasma levels of DEHP ranging from 0.34 to 0.83 mg/dl (approximately 0.02 mg/dl plasma per mg DEHP administered per square meter of surface area). The blood levels fell monoexponentially with a mean rate of 2.83 per cent per minute and a half-life of 28.0 minutes. Urine was assayed by a method that would measure unchanged DEHP as well as all phthalic acid-containing metabolites. In two patients, at most 60 and 90 per cent of the infused dose, respectively, was excreted in the urine collected for 24 hours posttransfusion. These estimates, however, could be high due to the simultaneous excretion of DEHP remaining from previous transfusions or arising from uncontrolled environmental exposures.     

Kinetics of humoral response in children with acute lymphoblastic leukemia immunized with influenza vaccine in 1993 in Poland

Songbirds exhibit seasonal changes in the volumes of song control nuclei. Birds on long, spring-like days have larger nuclei than do birds on short, winter-like days. The mechanisms mediating volumetric changes have not been determined unequivocally, but testosterone (T) is probably involved. This study examined whether testicular factors are uniquely responsible for seasonal changes in the song system, or whether photoperiod has testis-independent effects. Male American tree sparrows were exposed to one of three photoperiodic conditions: (1) Photosensitive birds were retained on short days (8L:16D). Plasma T is rarely detected in such birds. (2) Photosensitive birds were moved from short days to long days (20L:4D) and photostimulated for three weeks. Photostimulation elevates circulating T in photosensitive birds. (3) Photorefractory birds were held at least four months on 20L:4D. Such birds seldom have detectable levels of T, even though they are on long days. In each condition, there were both intact and castrated birds. Castration typically removes circulating T in tree sparrows. The volumes of the high vocal center (HVC), nucleus robustus archistriatalis (RA), and area X were measured. Song nuclei were largest in intact photostimulated birds. Other long-day birds (i.e. castrated photostimulated, and intact and castrated photorefractory groups) had larger song nuclei than did short-day intact or castrated photosensitive birds and did not differ from each other. These data indicate that photoperiod has both testis-dependent and -independent effects on the volumes of song control nuclei.     

Adjuvant treatment of high-risk breast cancer using multicycle high-dose chemotherapy and filgrastim-mobilized peripheral blood progenitor cells

Women with primary breast cancer associated with extensive axillary node involvement or large primary tumors have a very poor prognosis despite treatment with standard-dose adjuvant chemotherapy. In an attempt to improve the outlook of these patients, we investigated the safety and feasibility of delivering three cycles of high-dose epirubicin and cyclophosphamide supported with filgrastim-mobilized peripheral blood progenitor cells (PBPC). Fifteen previously untreated women, median age 50 (range, 30-58) years, with poor prognosis early stage breast cancer received filgrastim (12 microgram/kg daily for 6 days) prior to chemotherapy to mobilize progenitor cells. Patients were then given three cycles of epirubicin (200 mg/m2) and cyclophosphamide (4 g/m2) at planned 28-day intervals, each followed by infusion of one third of the PBPC collected and daily administration of filgrastim (5 microgram/kg s.c.). Three leukaphereses collected a median of 114.9 (range, 22.7-273.5) x 10(4) granulocyte-macrophage-colony-forming cells/kg body weight. Hemopoietic recovery was rapid after each cycle, and there was no correlation between the rate of recovery and the number of granulocyte-macrophage-colony-forming cells infused. There was a small but significant progressive delay in recovery from hematological and nonhematological toxicities across the three cycles. Left ventricular ejection fraction fell to below 50% in eight (53%) patients, but none developed congestive cardiac failure. Two patients did not complete three cycles because of insufficient PBPC for a third cycle (n = 1) and 2-mercaptoethane sodium sulfonate- related drug reaction during the second cycle (n = 1). There were no deaths during the study or during the follow-up period (median, 70 weeks; range, 50-85 weeks), and no late toxicities occurred. Therefore, we concluded that the delivery of multiple cycles of nonmyeloablative, dose-intensive chemotherapy supported by PBPC and filgrastim is safe, and may be widely applicable to a variety of common chemosensitive cancers with a poor prognosis. The efficacy of three cycles of high-dose epirubicin and cyclophosphamide is to be compared with standard-dose chemotherapy in a randomized trial in patients with high-risk, operable stage II and III breast cancer.     

联产二氯乙酸和巯基乙酸的研究

以氯乙酸母液为原料 ,采用硫代硫酸钠法将其转化为二氯乙酸和巯基乙酸 ,在反应温度 70℃ ,母液中一氯乙酸与硫代硫酸钠物质的量比为 1∶1,反应时间 4.5h ,还原用锌粉量为 8g,最佳反应条件下 ,可得到质量分数为 98.6 %的二氯乙酸 ,收率达 93% ;同时获得收率为 88%的巯基乙酸