Protection against lethal hyperoxia by tracheal insufflation of erythrocytes: role of red cell glutathione

Intact erythrocytes placed into the tracheobronchial tree of hyperoxic rats dramatically improved their chances for survival. Over 70 percent of the animals so treated survived more than 12 days during continuous exposure to 95 percent oxygen, whereas all of the control animals died within 96 hours. Lungs from erythrocyte-protected rats showed almost none of the morphologic damage suffered by untreated animals. Erythrocytes containing cyanomethemoglobin were as beneficial as normal erythrocytes, but cells in which glutathione was partially blocked were significantly less protective. Analogous results were obtained in vitro: 51Cr-labeled target cells released 70 to 90 percent of their label when exposed briefly to hydrogen peroxide or to toxic oxygen species generated by phorbol ester-stimulated neutrophils. Addition of intact erythrocytes decreased release by approximately 75 percent, but significantly less than this if red blood cell glutathione was partially blocked. These results suggest that insufflated erythrocytes, through their recyclable glutathione, protect rats from toxic oxygen species engendered by hyperoxia.     

Amyloidosis induced in mice by Escherichia coli endotoxin

Amyloidosis was produced in mice by repeated subcutaneous injections of 0.5-or 0.005-milligram amounts of Escherichia coli endotoxin. Of the two strains of mice examined, amyloidosis was induced more readily in one than in the other. The ability of endotoxin to induce amyloidosis lends support to the view that stimulation of reticuloendothelial cells leads to amyloid formation.     

Increased brain size and cellular content in infant rats treated with an opiate antagonist

From birth to day 21, rat offspring received daily injections of naltrexone at a dosage that blocked morphine-induced analgesia 24 hours a day. At 21 days, body, brain, and cerebellar weights of naltrexone-injected animals were 18, 11, and 5 percent greater than corresponding control weights. In addition, morphometric analysis of the cerebrum revealed a somatosensory cortex that was 18 percent thicker than that of the controls. The cerebellum of naltrexone-treated rats was 41 percent larger in total area and contained at least 70 percent more glial cells and 30 percent more granule neurons. Neurons derived prenatally were unaffected by drug treatment. These results show that naltrexone can stimulate body and brain growth in rats and suggest a role for the endorphin and opiate receptor system in development.     

p53 mutations in human cancers

Mutations in the evolutionarily conserved codons of the p53 tumor suppressor gene are common in diverse types of human cancer. The p53 mutational spectrum differs among cancers of the colon, lung, esophagus, breast, liver, brain, reticuloendothelial tissues, and hemopoietic tissues. Analysis of these mutations can provide clues to the etiology of these diverse tumors and to the function of specific regions of p53. Transitions predominate in colon, brain, and lymphoid malignancies, whereas G:C to T:A transversions are the most frequent substitutions observed in cancers of the lung and liver. Mutations at A:T base pairs are seen more frequently in esophageal carcinomas than in other solid tumors. Most transitions in colorectal carcinomas, brain tumors, leukemias, and lymphomas are at CpG dinucleotide mutational hot spots. G to T transversions in lung, breast, and esophageal carcinomas are dispersed among numerous codons. In liver tumors in persons from geographic areas in which both aflatoxin B1 and hepatitis B virus are cancer risk factors, most mutations are at one nucleotide pair of codon 249. These differences may reflect the etiological contributions of both exogenous and endogenous factors to human carcinogenesis.     

RETICULOENDOTHELIAL FUNCTION AND THE IMMUNE RESPONSE

Hyperphagocytic activity of the reticuloendothelial system induced in mice by the injection of glucan is associated with a significant increase in the primary and secondary immune responsiveness of these animals to sheep erythrocytes. Conversely, the administration of an agent which reduces endothelial phagocytosis is associated with significant depression of both primary and secnation of both factors.     

~(32)P的吸收、转运与甘蓝型油菜抗菌核病性的关系

用32P示踪法研究了不同抗性油菜品种3叶期及盛花期感染菌核病后磷素吸收与转运的变化。研究结果表明:磷素向着生长旺盛部位转运;接种后植株磷素吸收增强而且磷素向着接种叶富集,感病品种甚于抗病品种;经相关性分析,第2位叶(接种叶)、第3位叶磷素放射性活度提高幅度显著且与抗性成显著或极显著负相关。这说明磷素的吸收、转运与抗性有密切的关系。在盛花期,花果中磷素放射性活度呈上升趋势,宁RS-1和宁油7号叶中的磷素放射性活度都先上升后下降,但前者上升的幅度较大,而且后期下降缓慢;宁油7号茎中的磷素放射性活度呈稳定下降趋势,而宁RS-1表现为先上升后又下降。这说明抗病材料有较强的生理活性来抵抗病害。     

Response of 14C-Salicylic Acid to Heat Stress After Being Fed to Leaves of Grape Plants

An experiment was conducted to investigate the response of salicylic acid as a second messenger to the heat stress in grape plants. For this purpose, all leaves of grape (Vitis vinifera× V. labrussa L. cv. Jingxiu) plants were removed except the 3rd, 4th, 5th, 6th, and 7th ones. The 5th leaf was fed with 14C-SA, and the 4th and 6th leaves were exposed to high temperature at 40±0.5℃. It was observed that more 14C-SA transported out from the 5th leaf and the distribution of 14C-SA in each organ of plant altered in response to heat stress. The accumulation of 14C-SA in both the 4th and 6th leaves being exposed to high temperature was at least three times higher than that in control. The distribution of 14C-SA in other distal leaves (the 3rd and 7th leaf) decreased, but more 14C-SA accumulated in stems adjacent to the 4th or 6th leaf exposed to high temperature. In addition, there was more 14C-SA being transported upwards or downwards while the 4th and 6th leaves were exposed to high temperature respec tively. Therefore, our results suggested that SA was closely involved in signal transduction of heat stress in grape plants. However, the ratio of 14C radioactivity assayed after SA being extracted to that of direct assay with apparatus was more than 70%, which indicated about 30% 14C was lost or catabolized during transportation.     

牛肝脏肿瘤的调查和病理学研究

在内蒙古地区检验牛１０８６６７头，检出肝脏肿瘤７例，检出率为６．４４／１０万。其中恶性肿瘤有肝细胞癌４例，胆管细胞癌１例，胆管癌１例；良性肿瘤仅肝细胞腺瘤１例。恶性肿瘤为良性肿瘤的６倍。对４种牛肝脏肿瘤的形态和结构作了详细描述，并就其病理形态学特征和病因进行讨论。     

Methylation increases sodium transport into A6 apical membrane vesicles: possible mode of aldosterone action

When isolated apical membrane vesicles prepared from cultured A6 epithelia were incubated in vitro with the methyl donor S-adenosylmethionine, the control rate of amiloride-inhibitable sodium transport was doubled. The methylation inhibitors 3-deazaadenosine and S-adenosyl homocysteine returned the S-adenosyl-methionine-stimulated sodium transport to control levels. Neither these agents nor adenosine affected sodium transport into control vesicles. In vesicles incubated with S-adenosyl-[3H-methyl]methionine, both membrane phospholipids and proteins were labeled, and this labeling was inhibited by deazaadenosine. In vesicles prepared from A6 cells treated with aldosterone, sodium transport was twice the control value and S-adenosylmethionine did not cause any further stimulation of transport. In those vesicles, both lipid and protein methylation were increased. These results suggest that methylation, which increases the rate of amiloride-sensitive sodium transport is involved in the action of aldosterone at the apical membrane level in epithelia.     

A new approach to the adoptive immunotherapy of cancer with tumor-infiltrating lymphocytes

The adoptive transfer of tumor-infiltrating lymphocytes (TIL) expanded in interleukin-2 (IL-2) to mice bearing micrometastases from various types of tumors showed that TIL are 50 to 100 times more effective in their therapeutic potency than are lymphokine-activated killer (LAK) cells. Therefore the use of TIL was explored for the treatment of mice with large pulmonary and hepatic metastatic tumors that do not respond to LAK cell therapy. Although treatment of animals with TIL alone or cyclophosphamide alone had little impact, these two modalities together mediated the elimination of large metastatic cancer deposits in the liver and lung. The combination of TIL and cyclophosphamide was further potentiated by the simultaneous administration of IL-2. With the combination of cyclophosphamide, TIL, and IL-2, 100% of mice (n = 12) bearing the MC-38 colon adenocarcinoma were cured of advanced hepatic metastases, and up to 50% of mice were cured of advanced pulmonary metastases. Techniques have been developed to isolate TIL from human tumors. These experiments provide a rationale for the use of TIL in the treatment of humans with advanced cancer.     

Induction of choline phosphotransferase and lecithin synthesis in the fetal lung by corticosteroids

Rabbit fetuses 23 to 24 days of gestation were injected with either 9-fluoroprednisolone acetate or saline. Three days later the lungs of steroid-treated animals showed a significant increase in lecithin concentration and cholinephosphotransferase activity. In addition, lung slices from these animals incorporated more [(14)C]choline into lecithin. The rise in enzyme activity and [(14)C]choline incorporation was blocked by prior treatment of fetuses with cycloheximide but not by treatment with actinomycin D. It is proposed that the corticosteroids induce de novo synthesis of the lung enzyme, which in turn leads to increased synthesis of lecithin through the choline incorporation pathway. Furthermore, it appears that the site of regulation involves translation of messenger RNA.     

Uptake of glutamate into synaptic vesicles by an inorganic phosphate transporter

Previous work has identified two families of proteins that transport classical neurotransmitters into synaptic vesicles, but the protein responsible for vesicular transport of the principal excitatory transmitter glutamate has remained unknown. We demonstrate that a protein that is unrelated to any known neurotransmitter transporters and that was previously suggested to mediate the Na(+)-dependent uptake of inorganic phosphate across the plasma membrane transports glutamate into synaptic vesicles. In addition, we show that this vesicular glutamate transporter, VGLUT1, exhibits a conductance for chloride that is blocked by glutamate.     

Rat brain binds adrenal steroid hormone: radioautography of hippocampus with corticosterone

Tritiated corticosterone injected subcutaneously into adrenalectomized male rats 1 hour before killing produced intense labeling of the hippocampus in radioautograms prepared by a method that reduced or prevented diffusion of the radioactive material. The pyramidal neurons of the cornu ammonis and the granule neurons of the gyrus dentatus contained more radioactivity than did other regions of the brain; however, the intensity of labeling varied among adjacent neurons. The nuclei of many neurons were clearly labeled but radioactivity was relatively sparse in the cytoplasm, in the axons where they branch from cell bodies, and in adjacent neuropil.     

Quantal secretion from adrenal medulla: all-or-none release of storage vesicle content

Neurogenic secretion of catecholamines from the adrenal medulla in rabbits, induced by administration of insulin, caused decreases in both the dopamine-beta-hydroxylase activity and the catecholamine content of the storage vesicle fraction. After sedimentation through a sucrose density gradient, the storage vesicles obtained from insulin-treated animals had the same density and the same ratio of dopamine-beta-hydroxylase to catecholamine as did vesicles from untreated animals. These and other data indicate that neurogenic secretion from the adrenal medulla occurs by an all-or-none release from the storage vesicles.     

Effect of myasthenic immunoglobulin on acetylcholine receptors of intact mammalian neuromuscular junctions

Degradation of acetylcholine receptors of intact mouse neuromuscular junctions was determined in vivo and in vitro by the release of radioactivity from mouse diaphragms labeled with 125I-alpha-bungarotoxin. Treatment of mice with immunoglobulin from myasthenic patients accelerated the degradation rate to approximately three times normal, in both intact animals and organ cultures. The released radioactivity was in the form of [125I]tyrosine, confirming the nature of the degradative process. Accelerated degradation of acetylcholine receptors at neuromuscular junctions may represent an important antibody-mediated mechanisms in myasthenia gravis.     

Suppression of ovulation in the rat by an orally active antagonist of luteinizing hormone-releasing hormone

A synthetic antagonist of luteinizing hormone-releasing hormone blocked ovulation in rats in a dose-dependent manner when given by gavage on the afternoon of proestrus. Ovulation was delayed for at least 1 day in all animals given 2 milligrams of antogonist and in some of the animals treated with 1 or 0.5 milligram. Oral administration of 2 milligrams also blocked the preovulatory surge of luteinizing hormone. This demonstration that antagonists of luteinizing hormone-releasing hormone can have oral antiovulatory activity clearly enhances their therapeutic potential.     

THE INFLUENCE OF "FOLIC ACID" ON SPONTANEOUS BREAST CANCERS IN MICE

Complete regressions of spontaneous breast cancers in mice were observed in 38 among 89 animals (43 per cent.). The treatment consisted of daily intravenous injections of 5 micrograms of l. casei factor ("folic acid"). The treated animals lived longer than the controls, especially the healed mice. The incidence of the development of new tumors was decreased among the treated mice as compared with the controls.     

辽西半干旱区玉米大豆间作模式对作物干物质积累分配、产量及土地生产力的影响

[目的]通过分析玉米大豆间作模式作物干物质积累与分配规律及种间竞争关系,探讨玉米大豆间作的增产机理,提出适合辽西半干旱区的最优玉米大豆间作模式.[方法]试验于2018-2019年在国家农业环境阜新科学观测实验站进行,采用田间试验方法,设置2行玉米2行大豆间作(MS2:2)、4行玉米4行大豆间作(MS4:4)、6行玉米6...     

The twitch in horses: a variant of acupuncture

The twitch procedure in horses attenuates the increase in the heart rate evoked by pain-inducing stimuli and the reaction of the animals to such stimuli. Endorphin systems are probably involved in the effectiveness of the twitch, since its action is blocked by naloxone and its application increases plasma concentrations of immunoreactive beta-endorphin. The mode of action of the twitch cannot be explained by the generally accepted theory of divertive pain and may resemble that of classical acupuncture.