我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。     

Influence of kynurenines in pathogenesis of cataract formation in tryptophan-deficient regimen in Wistar rats

L-Tryptophan (Trp) is an essential amino acid and its deficiency is involved in various pathologies. In this present investigation an attempt was made to study the role of tryptophan and its metabolites in cataract formation in wistar rats. Rats were divided and maintained in 3 groups, Group A--control; Group B--marginal-tryptophan and Group C--Tryptophan-deficient diet for 3 months. Slit lamp microscope observations indicated lenticular opacities in Group-C (tryptophan-deficient) rats. In the rats that were maintained on tryptophan deficient diet, a decrease in protein content, kynurenines, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione-s-tranferase (GSTs) and tryptophan-fluorescence intensities and an increase in lipid peroxidation indicative of oxidative stress have been observed. The above changes were normalized in the rats on supplementation of 0.05% tryptophan (Group-B) in their diets. These results suggest that tryptophan-deficiency in the diet leads to an overall significant decrease in kynurenines and levels of antioxidant enzymes (except SOD) in ocular tissue with a concomitant lenticular opacification. The results suggest that diet with adequate tryptophan has protective influence and is of immense benefit in mitigating the changes that may otherwise contribute to the lenticular opacities.     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义.综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望.     

Isolation of influenza viruses in different species of bird in Canada in 1978

As part of the international program on the ecology of influenza virus in animals sponsored by W.H.O., 357 influenza A viruses isolated from 2 293 cloacal samples collected from ducks and other bird species in Eastern Canada during the 1978 season were characterized antigenically. Seven hemagglutinin (Hsw 1, H2, H3, Hav2, Hav4, Hav6, Hav7) and six neuraminidase subtypes (N1, N2, Neq2, Nav1, Nav5, Nav6) in 18 different combinations were found. A comparison with viruses isolated during previous seasons indicates that subtypes do change from year-to-year and from place-to-place. Isolation of few viruses from passerine birds requires additional studies to determine if these species are truly infected with influenza virus in nature. This large reservoir of influenza A viruses circulating at the same time in ducks may well be involved in the appearance of new viruses in other species, including humans.     

国内双歧杆菌制剂预防小儿继发性腹泻临床疗效的Meta分析

目的系统评价国内双歧杆菌制剂临床预防小儿继发性腹泻的效果。方法按照系统评价的要求检索CBMd isc、VIP、CNK I以及万方数据库等,获得18篇符合纳入标准的文献,共计患儿4050例,对其进行M eta分析,并评价M eta分析结果的稳定性和发表偏倚。结果异质性检验χ^2=34.60,P=0.007〈0.05,采用随机效应模型进行M eta分析,合并RR=0.41,95%C I为0.35～0.49,总体效应检验,Z=10.39,P〈0.00001,差异具有非常显著性,固定效应模型RR值和95%C I与随机效应模型完全一致,剔除小样本报道后的合并RR=0.42,95%C I为0.35～0.50,与剔除前的结果基本一致,且本研究的发表偏倚得到了很好地控制。结论从现有的临床证据来看,双歧杆菌制剂能降低小儿继发性腹泻的发生率,对预防小儿继发性腹泻起到了满意的效果。     

Measurement of in situ rates of nitrification in sediment

A method has been developed for the measurement of nitrification rates in intact sediment cores without disturbing the concentration gradients of oxygen and ammonium. N-serve (2-chloro-6-trichloromethyl-pyridine), a specific inhibitor of the autotrophic ammonium oxidation, was injected into a 0–2 cm surface layer of the sediment (20 ppm) and added to the water column of sediment cores (5 ppm). N-serve in these concentrations was sufficient to inhibit nitrification, but did not change the rate of ammonium production or incorporation in sediment suspensions, which were incubated aerobically and anaerobically. The ammonium accumulation in cores injected with N-serve was thus equal to the amount of ammonium which was oxidized to nitrate in the control cores. Nitrification rates were in the range of 0–3 mmol N m^{–2 –1}     

我国蝴蝶产业发展中亟待解决的几个问题

本文简略介绍了我国目前蝴蝶产业的背景情况和发展现状,着重阐述了该产业发展中亟待解决的目标与思路、政策与法律、科研与技术、人才与培养等一系列问题,并针地性提出了相应解决意见。     

Role of clozapine in the occurrence of chromosomal abnormalities in human bone-marrow cells in vivo and in cultured lymphocytes in vitro

Summary Bone-marrow chromosomes were examined from 38 mentally and physically retarded and two psychiatric patients who were being treated with a variety of neuropharmacologic drugs. Twenty of these patients used clozapine (Leponex^®). The clastogenic effects of clozapine in vitro were studied in the lymphocyte cultures of three patients-one free of hematologic disease and two who 6 months earlier had had agranulocytosis attributed to the use of clozapine. The mean frequency of cytogenetic abnormalities in the bonemarrow cells of patients who used clozapine was significantly increased (P> 0.05). The two patients who had had agranulocytosis had a greater frequency of cytogenetic abnormalities in their cultured lymphocytes in vivo and in vitro than the patient free of hematologic disease. A clone with a 13/14 chromosome translocation was detected in one of the patients. As all patients received a number of drugs during the in vivo and in vitro studies no definite conclusions could be drawn regarding the role played by clozapine in the occurrence of chromosomal abnormalities.     

Involvement of bioantioxidants in thrombosis in mice

SUMMARY

An involvement of free radicals in thrombosis has been suggested previously. In order to further explore the role of free radicals and antioxidants in thrombosis, we have measured preventive (enzymes of the glutathione redox cycle) and chain-breaking antioxidants (vitamin E and C) in whole blood, platelets, neutrophils (PMNLs), heart and lung following collagen and adrenaline induced thrombosis in mice. A significant decrease in platelet glutathione (GSH) level (54%) and glutathione reductase activity was observed after thrombosis. In addition, GSH content in whole blood was also found to be reduced. In PMNLs, an increase in glutathione peroxidase activity and a four-fold elevation in vitamin C content was observed following thrombosis. However, levels of vitamin E and total thiol groups remained unchanged in both the cells and tissues. The results further suggest involvement of free radicals and PMNLs in thrombosis.     

Transition of cancer in populations in India

Background & objectivesAn assessment of transition of cancer in India during the past 30 years, according to changes in demographic and epidemiologic risk factors was undertaken.Materials & methodsCancer registry data (http://www.ncdirindia.org), (population coverage <10%), was compared with transition in life-expectancy and prevalence on smoking, alcohol and obesity. We fitted linear regression to the natural logarithm of the estimated incidence rates of various cancer registries in India.ResultsBurden of cancer in India increased from 0.6 million in 1991 to 1.4 million in 2015. Among males, common cancers are lung (12.0%), mouth (11.4%), prostate (7.0%), and tongue (7.0%) and among females, they are breast (21.0%), cervix-uteri (12.1%), ovary (6.9%), and lung (4.9%) in 2012. Increased life-expectancy and population growth as well as increased use of alcohol and increased prevalence of overweight/obesity reflected an increase in all cancers in both genders except a reduction in infection-related cancers such as cervix-uteri and tobacco-related cancers such as pharynx (excludes nasopharynx) and oesophagus.Interpretation & conclusionTransition in demographics and epidemiologic risk factors, reflected an increase in all cancers in both genders except a reduction in a few cancers. The increasing incidence of cancer and its associated factors demands a planned approach to reduce its burden. The burden assessment needs to be strengthened by increasing the population coverage of cancer registries. Continued effort for tobacco prevention and public health efforts for reducing obesity and alcohol consumption are needed to reduce the cancer burden.     

Involvement of gonadotropins in induction of luteolysis in pigs

In our previous study we have demonstrated that treatment of endometrial explants with LH increased 13,14-dihydro-15-ketoprostaglandin F(2alpha) (PGFM) accumulation in pigs. This was particularly visible on Days 14-16 of the estrous cycle. Action of gonadotropin in porcine endometrium appears to be mediated by LH/hCG receptors whose number is dependent on the day of the estrous cycle. In the current study i.v. infusion (1 hour) of hCG (200 IU) performed on Days 10 (n=4) and 12-14 (n=4) of the porcine estrous cycle did not affect plasma PGFM (ng/ml+/-SEM) concentrations. In contrast, administration of hCG on Days 15-17 produced, depending on plasma PGFM level before the infusion period, three different types of response: I. plasma PGFM surge of amplitude 0.62+/-0.15 was observed when the mean basal pre-infusion PGFM plasma level was 0.23+/-0.05 (n=6 gilts); II. the delayed PGFM surge of amplitude 0.62+/-0.15 was determined when basal pre-infusion PGFM level was 0.80+/-0.20 (n=6); and III. lack of PGFM response to hCG was found when basal pre-infusion PGFM level was 1.09+/-0.61 (n=6). Concentrations of plasma PGFM before and after saline infusion did not differ on Days 12-14 and 16 of the estrous cycle. In the next experiment blood samples were collected every 1 hour on Days 12-19 of the estrous cycle to determine concentrations of LH, PGFM and progesterone in four gilts. In particular gilts, plasma peaks of LH closely preceded surges of PGFM in 72.7, 84.6, 75.0 and 66.6 percent, respectively. The highest PGFM surges followed a decline in plasma progesterone concentration. We conclude that the increased PGF(2alpha) metabolite production after hCG infusion during the late luteal phase of the estrous cycle as well as the relationship between plasma LH and PGFM peaks suggest the LH involvement in the elevation of endometrial PGF(2alpha) secretion in pigs, and, in consequence, induction of luteolysis.     

Application of in silico and in vitro methods in the development of adverse outcome pathway constructs in wildlife

There is a long history of using both in silico and in vitro methods to predict adverse effects in humans and environmental species where toxicity data are lacking. Currently, there is a great deal of interest in applying these methods to the development of so-called ‘adverse outcome pathway’ (AOP) constructs. The AOP approach provides a framework for organizing information at the chemical and biological level, allowing evidence from both in silico and in vitro studies to be rationally combined to fill gaps in knowledge concerning toxicological events. Fundamental to this new paradigm is a greater understanding of the mechanisms of toxicity and, in particular, where these mechanisms may be conserved across taxa, such as between model animals and related wild species. This presents an opportunity to make predictions across diverse species, where empirical data are unlikely to become available as is the case for most species of wildlife.     

Role of Ethylene in Induction of Flooding Damage in Sunflower

The possibility that symptoms of flooding damage in plants are primarily caused by an accumulation of ethylene was investigated using pot-grown sunflower (Helianthus annuus) plants. When plants were flooded to the basal pairs of leaves, ethylene in roots and stems below the water line began to increase. This coincided with the start of hypocotyl hypertrophy and new root formation in hypocotyls, which continued for 14-16 days. There were highly significant correlations between ethylene concentration and number of roots and hypocotyl diameter. After approximately 4 days of flooding, ethylene concentrations in stems between nodes for the 1st and 3rd basal pairs of leaves started to increase, coinciding with initiation of chlorophyll breakdown and epinasty of the 2nd basal pairs of leaves. Thus, there were correlations between ethylene concentration and chlorophyll breakdown and epinasty. The lower the leaves, the more chlorophyll breakdown among 1st, 2nd, 3rd, and 4th basal pairs of leaves. The longer the flooding, the more severe the flooding damage; and even when returned to normal condition, plants flooded longer than 3 days were not able to recover from flooding damage. A gas chromatographic study revealed that Ethephon was absorbed by roots and decomposed to ethylene in the plant. Damage symptoms caused by soil application of Ethephon, such as reduced stem height, chlorophyll breakdown, epinasty of the 2nd basal pairs of leaves, and hypocotyl hypertrophy, were almost identical with those caused by soil flooding treatment. Microscopic studies revealed that radially enlarged cells and increased intercellular spaces in the cortex were the major contribution to the increased hypocotyl diameter in both flooded and Ethephon-treated plants. It is concluded that the increase in ethylene concentration in flooded plants is largely, although not exclusively, responsible for flooding damage symptoms.     

Prevalence of Sarcocystis in Grackles in Maryland

SYNOPSIS. One hundred and fifty-nine grackles (Quiscalus quiscula) in Maryland were examined grossly and microscopically for Sarcocystis sp. Of 98 mature birds, 91 had Sarcocystis. None of 51 juvenile birds and none of 10 birds hatched in the laboratory had Sarcocystis. More mature females had Sarcocystis than did mature males. However, the number of intramuscular cysts (per bird) was greater in male grackles than in females. Both male and female grackles had more infections in the leg and thigh muscles than in breast muscles. No tongue or heart muscles contained Sarcocystis. No seasonal fluctuation in the number of infected birds was apparent.     

Residues of chlorinated hydrocarbons in tissues of raptors in Florida

Dead or moribund raptors (n = 75) representing 11 species were collected between 1971 and 1981 from various locations in Florida. Samples of bran, muscle, liver and adipose tissue were analyzed for DDT, DDE, DDD, dieldrin, and PCB's. Detectable concentrations of DDT or its metabolites were found in 100% of all samples of muscle and liver, and 77% all samples of brain. Dieldrin was determined to be present in 91%, 93%, 87% and 78% of all samples of brain, muscle, liver and adipose tissue, respectively. Lethal or hazardous concentrations of dieldrin were found in brain samples from three birds, but DDT and PCB's were present at sublethal concentrations. When species were grouped according to their dietary habits, it was not possible to identify any trends in pesticide concentrations.     

Role of telomerase in reactivation of macrophage nuclei in heterokaryons

It was shown that the duration of stay of macrophages in the peritoneal cavity of mice and method of their isolation did not affect markedly their capacity for resumption of DNA synthesis in heterokaryons. This means that mouse macrophage undergo such changes during differentiation that reactivation of DNA synthesis in their nuclei is only possible after interaction of telomeres with telomerase, since it was already shown that telomerase was involved in reactivation of DNA synthesis in the macrophage nuclei. The results of experiments did not reveal differences in the length of telomeres in mouse macrophages and other somatic cells. This could depend on the significant length of mouse telomeres and, as a result, their shortening, sufficient for the inhibition of proliferation, is beyond the limits of sensitivity of the current methods. It is also possible that changes in DNA properties in the macrophages occurring during their differentiation depend on changes in the conformation of the telomere complex in these cells. Testing of this suggestion is relevant with respect to recent data that cell hybridization, specifically in the form of heterokaryons, may be essential in realization of the therapeutic effect caused by the introduction of cells during cell therapy.     

Studies of in vivo mutations in rpsL transgene in UVB-irradiated epidermis of XPA-deficient mice

We have established xeroderma pigmentosum group A (XPA) gene-knockout mice with nucleotide excision repair (NER) deficiency, which rapidly developed skin tumors when exposed to a low dose of chronic UV like XP-A patients, confirming that the NER process plays an important role in preventing UVB-induced skin cancer. To examine the in vivo mutation in the UVB-irradiated epidermis, we established XPA (−/−), (+/−) and (+/+) mice carrying the Escherichia coli rpsL transgene with which the mutation frequencies and spectra in the UVB-irradiated epidermal tissue can be examined conveniently. The XPA (−/−) mice showed a higher frequency of UVB-induced mutation in the rpsL transgene with a low dose (150 J/m²) of UVB-irradiation than the XPA (+/−) and (+/+) mice, while, at a high dose (900 J/m²) they showed almost the same frequency of mutation as the XPA (+/−) and (+/+) mice, probably because of cell death in the epidermis of the XPA (−/−) mice. However, CC→TT tandem transition, a hallmark of UV-induced mutation, was detected at higher frequency in the XPA (−/−) mice than the XPA (+/−) and (+/+) mice at both doses of UVB. This rpsL/XPA mouse system will be useful for further analyzing the role of NER in the mutagenesis and carcinogenesis induced by various carcinogens.     

Involvement of nitric oxide in inflammation of ovaries in gilts

NADPH-diaphorase (NADPH-d) and an inducible type of nitric oxide synthase (iNOS) were demonstrated in porcine ovaries after unilateral infusion of bacteria into the hilus of an ovary. In group I one ml of saline was infused into the hilus of each ovary from the 15th day to the 19th day of the estrous cycle. In group II one ml of bacterial suspension (10(9) colony forming units of Escherichia coli, Staphylococcus aureus and Corynebacterium pyogenes, in a proportion 1:1:1, respectively) in saline was infused into the hilus of one ovary on days corresponding to those of the control group (gr. I), whereas saline was infused into the contralateral ovary. The ovaries were collected on the 7th day of the next estrous cycle. In the bacteria-treated ovary, the activity of NADPH-d was higher in the endothelium of blood vessels, corpora lutea and follicular walls in comparison to that observed in the respective structures of the contralateral ovary. The highest activity of NADPH-d was found in the vascular endothelium in the bacteria-infused ovary. Vascular smooth muscle cells found in both ovaries of the bacteria-treated gilts were more intensely stained for NADPH-d than those in control animals. After bacteria administration, the intensity of NADPH-d reaction in all the structures of both ovaries in group II was higher than in control group. The strongest immunostaining for iNOS was observed in all structures of the bacteria-infused ovary. In the contralateral ovary, iNOS-immunoreactivity was weaker but still stronger than that in control group. The present results revealed that infusions of bacteria into the hilus of one ovary enhanced the activity of NADPH-d and immunoreactivity for iNOS in both porcine ovaries. However, the activity of both enzymes was higher in the bacteria-infused ovary than in the contralateral one. These data suggest that locally synthesized NO can mediate an inflammatory effect of bacteria in the porcine ovaries.     

Alteration of mitochondrial function in a model of chronic ischemia in vivo in rat heart

The aim of this study was to investigate mitochondrial alterations in an animal model of chronic myocardial ischemia in rats obtained by surgical constriction of the left coronary artery. Resting coronary blood flow was measured using the fluorescent microsphere technique. Contractile function, defined by rate-pressure product, and myocardial oxygen consumption were measured in a Langendorff preparation. The mitochondrial function was evaluated on permeabilized skinned fibers. Three weeks after surgery, ischemic hearts showed a significant decrease in coronary blood flow compared with sham. Hemodynamic measurements showed a significant systolic and diastolic dysfunction. Alterations in mitochondrial function in ischemic hearts were mainly characterized by a significant decrease in the maximal velocity and apparent half-saturation constant for ADP, loss of the stimulatory effect of creatine, and a stimulatory effect of exogenous cytochrome c. These functional alterations were supported by structural alterations characterized by mitochondrial clustering and swelling associated with membrane rupture. We conclude that the alterations in systolic function after chronic ischemia are supported by severe modifications of mitochondrial structure and function.