石榴离体培养再生体系的研究

对石榴休眠枝段、成熟叶片及当年生新梢离体培养 ,建立其再生体系。结果表明 ,以休眠枝段、成熟叶片为外植体均能形成愈伤组织并分化出不定芽 ;当年生新梢茎段培养 ,以MS +BA 2 0mg·L-1+NAA0 3mg·L-1对茎段腋芽的增殖最适宜。诱导生根 ,用 1/2MS为基本培养基附加NAA 0 5mg·L-1+活性炭0 1mg·L-1+蔗糖 2 0g·L-1,生根率达 95 8%。培养基中附加 0 1%活性炭 ,对促进生根均有显著效果。     

黄金梨的组织培养和快繁研究

采用黄金梨二年生树的春梢为试材 ,进行组织培养 ,结果表明 ,适宜的诱导产生不定芽的培养基为AS + 6 -BA 1 .5～ 2 .0mg·L- 1,增殖培养基为ASH +NAA 0 .5mg·L- 1+IBA(或IAA) 0 .5mg·L- 1+AC50 0mg·L- 1。试管苗在自然光下炼苗 1周 ,再开瓶口炼苗 3天 ,移栽成活率达 97%。     

鹤望兰无性繁殖试验初探

分别采用鹤望兰的种子和短茎切段作外植体进行了组织培养 ,结果表明 :两种外植体在加入高浓度 6 BA (2 0mg·L- 1 )的培养基和低浓度 6 BA (3～ 7mg·L- 1 )的培养基上交替培养 ,既能防止褐化 ,又能获得再生芽。种子切段培养是通过类似原球茎的方式再生 ,短茎切段是通过愈伤组织途径再生     

‘黄水蜜’桃实生苗茎段再生体系的建立

【目的】建立‘黄水蜜’桃实生苗茎段高效稳定的再生体系。【方法】以‘黄水蜜’桃实生苗茎段为外植体,探讨了不同植物生长调节剂质量浓度组合对不定芽诱导过程中愈伤组织形成率和不定芽形成率的影响,并采用两步生根法研究不同植物生长调节剂种类对不定根诱导的影响。【结果】适合‘黄水蜜’桃实生苗茎段切口处愈伤组织再生的最佳培养基为MS+6-BA 2.0 mg·L-1+NAA 0.5 mg·L-1+Ag NO30.5 mg·L-1,不定芽再生的最佳培养基为MS+6-BA 3.0mg·L-1+NAA 0.1 mg·L-1+Ag NO30.5 mg·L-1,其愈伤组织形成率和不定芽再生率分别为85%和47%;获得的不定芽先后经WPM+ZT 2.0 mg·L-1+NAA 0.1 mg·L-1+Ag NO30.5 mg·L-1和MS+NAA 0.5 mg·L-1+GA30.5 mg·L-1+Ag NO30.5mg·L-1两步生根法培养后,不定根再生率为50%,平均根数量为5.00。【结论】初步建立了‘黄水蜜’桃实生苗茎段再生体系,为桃遗传转化研究奠定基础。     

锥栗植株再生体系的建立

【目的】为了建立锥栗再生体系,【方法】以锥栗胚为外植体,分析不同基因型、基本培养基及激素组合对锥栗不定芽的诱导、增殖和生根的影响。【结果】结果表明,油榛是锥栗组织培养最佳的基因型;锥栗不定芽诱导的最适培养基为M(NH4NO3804 mg·L-1+KNO31011 mg·L-1+FeSO4.H2O 27.8 mg·L-1+1/2MS其余无机盐+MS有机)+6-BA 2.0mg·L-1+IBA 0.2 mg·L-1,其出芽率为76%;芽增殖的最佳培养基为M(同上)+6-BA 0.5 mg·L-1+IBA 0.1 mg·L-1,其增殖倍数达18;诱导生根的最佳培养基为M(同上)+IBA 0.5 mg·L-1,其生根率为48%。【结论】运用上述体系可获得完整锥栗再生植株。     

猕猴桃实生组培快繁体系的建立

为建立猕猴桃实生组培快繁体系,以"徐香"种子为外植体,开展种子清毒、种子萌发诱导、实生苗茎段继代增殖培养、生根培养各阶段方案筛选试验。结果表明,75%酒精消毒30 s,0.1%HgCl_2消毒8 min为外植体最佳消毒方法,成活率达79.18%;种子萌发诱导最佳培养基为MS+100 mg/L肌醇+20 g/L蔗糖+6 g/L琼脂;适宜的增殖培养基为MS+1.0 mg/L 6-BA+0.1 mg/L NAA+20 g/L蔗糖+6 g/L琼脂;生根培养基以1/2MS+0.4 mg/L IBA+20 g/L蔗糖+6 g/L琼脂最好;选用草炭土和珍珠岩(体积比4∶1)移栽,植株根系包被苔藓,组培苗成活率达80%以上。     

桃叶片再生不定芽的研究

以桃栽培品种曙光、金童5号和甜桃王试管苗叶片为外植体,研究了基本培养基、植物生长调节剂种类及质量浓度组合、基因型和试管苗继代次数等因素对叶片再生的影响。结果表明,适宜暗培养的培养基为LP+1.5mg·L-1TDZ+0.15mg·L-1NAA;光培养基为LP+0.5mg·L-1TDZ+0.3mg·L-1KT+0.3mg·L-1NAA和LP+0.6mg·L-1TDZ+0.3mg·L-1KT+0.4mg·L-12,4-D;金童5号和曙光具有较强的再生能力,再生率分别为21.8%和14.5%;曙光和金童5号试管苗继代第1～11次叶片的再生能力与继代前3次愈伤组织相比形成率较高;曙光再生苗在培养基1/2MS+0.5mg·L-1NAA上生根率为100%,平均生根条数为7.9。     

食用百合种质的玻璃化法超低温保存技术初探

以离体茎尖为试材 ,采用玻璃化法 ,对食用百合离体超低温保存技术进行了初步研究。结果表明 ,用2～ 3mm茎尖 ,在MS +0 .5mol·L-1蔗糖浓度的培养基上预培养 1～ 2d ,室温下植物玻璃化溶液 (PVS2 )处理 2 0min ,换入新鲜的PVS2 ,迅速投入液氮中 ,2d后取出 ,在 4 0℃水浴中解冻 2min ,再在 2 5℃水浴中解冻 10min ,用1.2mol·L-1蔗糖液体培养基洗涤 2 0min ,接种在 6 -BA 0 .5mg·L-1+NAA 0 .1mg·L-1+GA3 0 .3mg·L-1+蔗糖 30 g·L-1+琼脂 7g·L-1的MS培养基上 ,2 5℃弱光培养 1周后转为正常光下培养 ,2周后再生率达到 5 2 .6 %。     

酸枣愈伤组织转化体系构建及在ZjBRC1调控ZjYUCCA表达中的应用

以来源于同一株酸枣实生苗的茎段、叶片、子叶和胚轴等组织为外植体试材,筛选到适合子叶、胚轴和叶片诱导愈伤组织的培养基为MS+1.0 mg·L-12,4-D+0.4 mg.L-1 TDZ;利用农杆菌介导法,当浸染液浓度OD600为0.6～0.8、浸染时间为30 min时,酸枣叶片、子叶、胚轴和茎段愈伤组织遗传转化率分别为3...     

黑穗醋栗组织培养和遗传转化

通过对不同激素质量浓度配比实验,建立黑穗醋栗茎尖高频再生体系。结果表明,MS+6-BA1.0mg·L-1+NAA0.1mg·L-1培养基可高效诱导黑穗醋栗茎尖的分化,1/2MS培养基可快速诱导根的生成,形成再生植株。25mg·L-1卡那霉素可以抑制茎尖的分化,20mg·L-1卡那霉素可以抑制分化小苗的生根。利用农杆菌介导法将osMAPK4基因转化黑穗醋栗,获得了抗卡那霉素的再生植株。提取转基因植株基因组DNA,进行PCR检测,结果表明osMAPK4基因已经被整合到黑穗醋栗基因组中。     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [³-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10^-6-10^-4 mmol/L) stimulated [³-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [³-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10^-6-10^-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl₂ for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.