H－ras在颊粘膜正常、良性、癌前及恶性变上皮中的表达：免疫组织化学定量研究

本文通过建立图象分析方法对免疫组织化学反应结果进行定量,检测观察Ｈ－ｒａｓ在口腔颊粘膜上皮在正常（Ｎ）、慢性炎症（ＩＦ）、癌旁上皮（ＥＡＣ）和鳞癌（ＳＣＣ）的变化过程中的表达并进行分析。结果显示Ｈ－ｒａｓ在ＳＣＣ组中,以中等分化的ＳＣＣ无论是Ｈ－ｒａｓ表达的量还是细胞阳性率都较高。此外,组织学观察显示,Ｈ－ｒａｓ在处于分化末期但尚未角化的正常上皮细胞中有较高的表达。本文结果显示了Ｈ－ｒａｓ的过表达与上皮细胞的会化程度密切相关。本研究还显示,所采用的阳性区域透光值、平均总透光值及阳性反应区域与阴性反应区域比值可靠并有相关性。这进一步说明了用免疫组化定量方法检测Ｈ－ｒａｓ癌基因表达的精确和可靠性。     

Isolation and characterization of plasma membrane-associated cortical granules from sea urchin eggs

Cortical granules, which are specialized secretory organelles found in ova of many organisms, have been isolated from the eggs of the sea urchins Arbacia punctulata and Strongylocentrtus pupuratus by a simple, rapid procedure. Electron micropscope examination of cortical granules prepared by this procedure reveals that they are tightly attached to large segments of the plasma membrane and its associated vitelline layer. Further evidence that he cortical granules were associated with these cell surface layers was obtained by (125)I-labeling techniques. The cortical granule preparations were found to be rich in proteoesterase, which was purified 32-fold over that detected in a crude homogenate. Similarly, the specific radioactivity of a (125)I-labeled, surface glycoprotein was increased 40-fold. These facts, coupled with electron microscope observations, indicate the isolation procedure yields a preparation in which both the cortical granules and the plasma membrane-vitelline layer are purified to the same extent. Gel electrophoresis of the membrane-associated cortical granule preparation reveals the presence of at least eight polypeptides. The major polypeptide, which is a glycotprotein of apparent mol wt of 100,000, contains most of the radioactivity introduced by (125)I-labeling of the intact eggs. Lysis of the cortical granules is observed under hypotonic conditions, or under isotonic conditions if Ca(2+) ion is present. When lysis is under isotonic conditions is induced by addition of Ca(2+) ion, the electron-dense contents of the granules remain insoluble. In contrast, hypotonic lysis results in release of the contents of the granule in a soluble form. However, in both cases the (125)I-labeled glycoprotein remains insoluble, presumably because it is a component of either the plasma membrane or the vitelline layer. All these findings indicate that, using this purified preparation, it should be possible to carry out in vitro studies to better define some of the initial, surface-related events observed in vivo upon fertilization.     

Lectin-binding sites on the plasma membranes of rabbit spermatozoa: Changes in surface receptors during epididymal maturation and after ejaculation

Modifications in rabbit sperm plasma membranes during epididymal passage and after ejaculation were investigated by used of three lectins: concanavalin A (Con A); Ricinus communis I (RCA(I)); and wheat germ agglutinin (WGA). During sperm passage from caput to cauda epididymis, agglutination by WGA drastically decreased, and agglutination by RCA(I) slightly decreased, although agglutination by Con A remained approximately unchanged. After ejaculation, spermatozoa were agglutinated to a similar degree or slightly less by Con A, WGA, and RCA(I), compared to cauda epididymal spermatozoa. Ultrastructural examination of sperm lectin-binding sites with ferritin- lectin conjugates revealed differences in the densities of lectin receptors in various sperm regions, and changes in the same regions during epididymal passage and after ejaculation. Ferritin-RCA(I) showed abrupt changes in lectin site densities between acrosomal and postacrosomal regions of sperm heads. The relative amounts of ferritin-RCA(I) bound to heads of caput epididymal or ejaculated spermatozoa. Tail regions were labeled by ferritin RCA(I) almost equally on caput and cauda epididymal spermatozoa, but the middle-piece region of ejaculated spermatozoa was slightly more densely labeled than the principal-piece region, and these two regions on ejaculated spermatozoa were labeled less than on caput and cuada epididymal spermatozoa. Ferritin-WGA densely labeled the acrosomal region of caput epididymal spermatozoa, although labeling of cauda epidiymal spermatozoa was relatively sparse except in the apical area of the acrosomal region. Ejaculated spermatozoa bound only a few molecules of ferritin-WGA, even at the highest conjugate concentrations used. Caput epididymal, but not cauda epididymal or ejaculated spermatozoa, bound ferritin-WGA in the tail regions. Dramatic differences in labeling densities during epididymal passage and after ejaculation were not found with ferritin-Con A.     

Phylogenetic utility of the nuclear gene arginine decarboxylase: an example from Brassicaceae

Arginine decarboxylase (ADC) is an important enzyme in the production of putrescine and polyamines in plants. It is encoded by a single or low-copy nuclear gene that lacks introns in sequences studied to date. The rate of Adc amino acid sequence evolution is similar to that of ndhF for the angiosperm family studied. Highly conserved regions provide several target sites for PCR priming and sequencing and aid in nucleotide and amino acid sequence alignment across a range of taxonomic levels, while a variable region provides an increased number of potentially informative characters relative to ndhF for the taxa surveyed. The utility of the Adc gene in plant molecular systematic studies is demonstrated by analysis of its partial nucleotide sequences obtained from 13 representatives of Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order Capparales) and 1 from the related order Malvales. Two copies of the Adc gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied to data except the basal genus Aethionema. The resulting Adc gene tree provides robust phylogenetic data regarding relationships within the complex mustard family, as well as independent support for proposed tribal realignments based on other molecular data sets such as those from chloroplast DNA.      

Effects of aerobic exercise therapy and cognitive behavioural therapy on functioning and quality of life in amyotrophic lateral sclerosis: protocol of the FACTS-2-ALS trial

Background

Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.

Methods

We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.

Results

Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.

Conclusions

The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.     

Plasma C-reactive protein is not elevated in physically active postmenopausal women taking hormone replacement therapy.

We tested the hypothesis that hormone replacement therapy (HRT)-related increases in C-reactive protein (CRP) would either be blunted or absent in postmenopausal women who regularly perform endurance exercise. Plasma CRP is an independent predictor of future cardiovascular events in healthy men and women. Oral HRT increases plasma CRP concentrations in postmenopausal women. Regular aerobic exercise reduces the risk of cardiovascular events and is associated with lower CRP concentrations in adults. To date, no study has evaluated the influence of habitual physical activity on the elevation of CRP associated with HRT. Plasma CRP concentrations were measured in 114 postmenopausal women: 39 physically active (endurance trained) and 75 sedentary postmenopausal subjects. Sixty-five women were users of HRT (22 physically active and 43 sedentary), and 49 were nonusers (17 physically active and 32 sedentary). CRP levels were approximately 75% higher (P < 0.01) in the sedentary users vs. nonusers of HRT (1.9 +/- 1.8 vs. 1.1 +/- 1.0 mg/l). In contrast, there was no difference in CRP levels between the physically active users and nonusers of HRT (0.6 +/- 0.4 vs. 0.4 +/- 0.2 mg/l; P = 0.61). Regardless of HRT status, CRP concentrations were approximately 65% lower in the physically active compared with sedentary women. In conclusion, physically active postmenopausal women exhibit lower plasma CRP concentrations compared with sedentary controls. Importantly, the HRT-related elevation in plasma CRP levels observed in sedentary women is absent in women who engage in regular endurance exercise. These data suggest that habitual physical activity may prevent the elevation in CRP concentrations due to HRT.     

Chromosome numbers and meiotic analysis in the pre-breeding of <Emphasis Type="BoldItalic">Brachiaria decumbens</Emphasis> (Poaceae)

A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them, 15 accessions presented 2n = 18; 27 accessions, 2n = 36; and 2 accessions, 2n = 45 chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions.     

游仆虫信息素Er-1和Er-2对四膜虫的种间作用

信息素是生物体向外释放的化学物质,在细胞及生物体中具有种内信息传递的生理学功能。信息素这一类分子广泛分布于系统发生史中,它们的特异活性在单细胞生物、昆虫以及脊椎动物中均有报道。脊椎动物中信息素的信号传输已被证实是一嗅觉依赖过程,7TM-受体被认为是信号传输过程中的信号转换器。在低等单细胞生物(例如:来可夫游仆虫)的细胞膜上存在有信息素异构体,作为信息素分子的有效结合位点而行使其功能。本研究主要探讨单细胞的信息素(Er-1和Er-2)的基础细胞生理学作用是仅限于产生该信息素的物种,还是对其它的原生动物(例如:四膜虫)或对系统发育中分类地位较高的细胞(例如:MRC5成纤维细胞或J774巨噬细胞)均具有调节活性。研究结果表明,游仆虫的两种信息素对梨形四膜虫GL的生长调节有显著不同的作用:当信息素浓度为10-11M时,Er-1具有正调控作用,而Er-2具有抑制剂的作用。这两种配体的趋化作用也有很不同:Er-1具有一种广范的化学排斥特性,而Er-2具有一个双峰的化学吸引剂的性质。计算机检测发现,与Er-2的作用不同,Er-1可略微降低被测细胞的游动速率。趋化现象的选择特性表明Er-2信息素的受体有一种“短期”的特性;而Er-1是不能选择任何亚种群的,这也支持了我们先前的研究数据,即这两种信息素在四膜虫GL内产生两种不同的信号。四膜虫对信息素特异性的反应表明四膜虫能辨别非常近似但带有微小差异的配体(如Er-1和Er-2的电荷差异)。     

Regulation of the adaptation to zinc deficiency in plants

The molecular mechanisms by which plants sense their micronutrient status, and adapt to their environment in order to ensure a sufficient micronutrient supply, are poorly understood. Zinc is an essential micronutrient for all living organisms. when facing a shortage in zinc supply, plants adapt by enhancing the zinc uptake capacity. The molecular regulators controlling this adaptation were recently identified. in this mini-review, we highlight recent progress in understanding the adaptation to zinc deficiency in plants and discuss the future challenges to fully unravel its molecular basis.Key words: adaptation, zinc deficiency, biofortification, molecular regulators, plant nutritionIn an increasingly populated world, agricultural production is an essential element of social development. Agriculture is the primary source of all nutrients required for human life, and nutrient sufficiency is the basis for good health and welfare of the human population.¹ Soils with zinc deficiency are widespread in the world, affecting large areas of cultivated soils in India, Turkey, China, Brazil and Australia,^2,3 making zinc the most common crop micronutrient deficiency.⁴ In addition, risk of inadequate zinc diet and zinc malnutrition are estimated to affect one-third of the global human population, i.e., around two billion people.⁵ Most affected are people living in developing countries, where diets are rich in cereal-based foods. Cereal grains are rich in phytate, which is a potent anti-nutrient, limiting micronutrient bioavailability.⁶ Zinc deficiency in crop production can be easily ameliorated through zinc fertilization, making agronomic biofortification an important strategy,³ however in the poorer regions, the required infrastructure to provide a reliable supply of zinc fertilizers of sufficient quality, is often not available. In those situations, biofortified crops, in which the zinc status of crops is genetically improved by selective breeding or via biotechnology, offer a rural-based intervention that will more likely reach the population.⁷ Different traits can be targeted to developing such improved crops, such as plant zinc deficiency tolerance, zinc use efficiency and the accumulation of zinc in edible parts. However, insufficient knowledge on the molecular mechanisms and the regulation of the zinc homeostasis network in plants is a serious bottleneck when pursuing zinc biofortification.