Calcium transport mechanisms in dog red blood cells studied from measurements of initial flux rates

Ca2+ efflux from dog red blood cells loaded with Ca2+ using the A23187 ionophore could be separated into two main components: (1) Mg- and ATP-dependent (active transport) and (2) dependent on external Na (K1/2 around 15 mM); at 80 microM internal free Ca the relative magnitudes of these fluxes were 70% and 30% respectively. The Na-dependent Ca2+ efflux had the following additional properties: (i) it was partially inhibited by ATP depletion or preincubation with vanadate, but it was not affected by Mg2+ depletion; (ii) it failed to be stimulated by external monovalent cations other than Na: (iii) it was stimulated by reduction in the internal Na+ concentration. Both active and Na-dependent Ca2+ efflux remained unchanged in hypotonic solutions or in solutions with alkaline pH (8.5). In cells containing ATP and Mg2+, external Ca2+ inhibited Ca2+ efflux (K1/2 around 1 mM); on the other hand, in Mg-free dog red cells external Ca2+ stimulated Ca2+ efflux (K1/2 about 30 microM). In Mg-depleted red cells incubated in the absence of external Na2+, Ca2+ influx as a function of external Ca2+ followed a monotonically saturable function (K1/2 around 20 microM): addition of Na resulted in (i) inhibition of Ca2+ influx and (ii) a sigmoid relationship between flux and external Ca2+. Intracellular Ca2+ stimulated the external Na-dependent Ca2+ efflux along a sigmoid curve (K1/2 around 30 microM); on the other hand the Ca pump had a biphasic response to internal Ca2+: stimulation at low internal Ca2+ (K1/2 between 1 and 10 microM), followed by a decline at internal Ca2+ concentrations higher than 50 microM.     

Evidence that insulin and concanavalin-A can co-bind to solubilized insulin receptors without inhibiting each other

Concanavalin A (Con A) precipitates detergent-solubilized insulin receptors (free of or bound to [${}^{125}\text{I}$]insulin) prepared from fat cell membranes resulting in a loss of [${}^{125}\text{I}$]insulin binding capacity (or bound hormone) in the soluble fraction. The losses can be recovered by redissolving the precipitates with methyl-α-D-mannoside; the sugar also inhibits precipitation. [${}^{125}\text{I}$]insulin also binds to insoluble Con A-occupied receptors. At all concentrations of Con A tested, the initial amounts of free or hormone-bound receptors were completely accounted for by their distribution between soluble and insoluble states. We conclude that Con A and insulin can co-bind to independent sites on the insulin receptor without inhibiting each other and that previously reported decreases in insulin binding to solubilized insulin receptors were likely due to precipitation by Con A of the receptors.     

Uptake of proteinase-α-macroglobulin complexes by macrophages

Complexes of labelled proteinases (subtilopeptidase A, trypsin) with serum α₁-macroglobulin or α₂-macroglobulin are rapidly taken up in vitro by rabbit alveolar macrophages and peritoneal macrophages but not by mixed rabbit peripheral blood leukocytes. Enzyme, not bound to α₁ - or α₂ -macrogobulin, does not become associated with alveolar macrophages. Chemically inactivated subtilopeptidase A does not bind to α₁ - or α₂ -microglobulin, does not interact with alveolar macrophages. Blocking experiments confirmed that the interaction of proteinase with alveolar macrophages is complex specific; uptake of labelled complex was prevented by the simultaneous addition of macroglobulin complexes formed with non-labelled subtilopeptidase A, subtilopeptidase B, trypsin or chymotrypsin but not by macroglobulin alone. The findings demonstrate a complex-specific interaction between proteinase-α-macroglobulin complexes and macrophages.     

New Taxa of Chinese Aristolochia L.

Four new species of the genus Aristolochia (Aristolochiaceae) are described as new from China. They are Aristolochia austrochinensis C. Y. Cheng & J. S. Ma, A. caulialata C. Y. Wu, A. salweenensis C. Y. Cheng & J. S. Ma, and A. kunmingensis C. Y. Cheng &J. S. Ma. A naturalized species, A. ringens Vahl is also reported.     

中国链格孢属的研究I.(英)

本文报道链格孢属的2个新种：寄生在苦木科（Simaroubaceae）臭椿［Ailanthusaltissima（Mill.）Swingle]上的臭椿链格孢（Alternariaailanthispnov）,寄生在桦木科（Betulaceas）黑桦（BetuladahuricaPall.）上的桦木链格孢（A．betalaesp．nov．）,2个新组合：豆链格孢［A．azukiae(Hara)comb.nov.],蔷薇生链格孢[A.rosicola（Rao）comb.nov.]和1个新名称红花链格孢（A．carthami-tinctoriinom．nov）。文中为新种提供了拉丁文简介、描述和图。模式标本保藏在山东农业大学植物病理标本室（HSAUP）。     

Materials for Chinese Ainsliaea (Compositae)

The genus, Ainsliaea DC. from China is revised in this paper. Three species, A. nana Y. C. Tseng, A. pingbianensis Y. G. Tseng and A. trinervis Y. C. Tseng, are newly described; two species, A. chapaensis Merr. and A. angustifolia Hook. f. et Thoms. ex C. B. Clarke are new records for China and two new combinations, A. apteroides (Chang) Y. C. Tseng and A. macrocephala (Mattf.) Y. C. Tseng, are made. In addition, one species, A. hypoleuca Diels ex Limpr. and four varieties, A. bonatii Beauverd var. arachnoidea Beauverd, A. pteropoda DC. var. leiophylla Franch., A. elegans Hemsl. var. tomentosa Mattf. and A. glabra Hemsl. var. tenuiculis (Mattf.)Chang, are reduced to synonyms.     

3种园蛛幼蛛各龄形态比较

实验室恒温条件下,研究了园蛛属3种园蛛——角园蛛(Araneus cornutus),叶斑园蛛(A.sta),大腹园蛛(A.ventricosus)的各龄幼蛛。描述它们各自的形态特征;指出它们之间的形态差异。     

Identification and quantification of endogenous gibberellins in apical buds and the cambial region of Eucalyptus

Endogenous gibberellins (GAs) were extracted and purified from apical buds of Eucalyptus nitens (Deane and Maid.) Maid. and the cambial region of E. globulus (Labill.). then analysed by capillary gas chromatography-mass spectrometry. GA₁ GA₁₉ GA₂₀ and GA₂₉ were identified by full scan mass spectra. Kovats retention indices and high resolution selected ion monitoring. Using deuterated internal standards. GA₁. GA₁₉. GA₂₀ and putative GA₂₉ and GA₅₃ were quantified in the apical buds, while GA₄. GA₈. GA₉ and GA₄₄ were shown to be either absent or present at very low levels. From the cambial region. GA₁ and GA₂₀ were quantified at levels of 0.30 ng (g fresh weight)-¹ and 8.8 ng (g fresh weight)-¹ respectively. These data suggest that the early 13-hydroxylation pathway is the dominant pathway for GA biosynthesis in Eucalyptus .     

Clinical relevance of the cagA,vacA and iceA genotypes of Helicobacter pylori in Brazilian clinical isolates

Infection with Helicobacter pylori strains harboring determinants of pathogenicity may lead to a strong inflammatory response in gastric mucosa. In this work, we examined the frequency of the cagA, vacA and iceA genotypes in H. pylori strains isolated from Brazilian patients and correlated these with the clinical manifestations. H. pylori was isolated from 165 patients [30 with non-ulcer dyspepsia cases (NUD); 93 peptic ulcer disease (PUD): 31 gastric ulcers (GU) and 62 duodenal ulcer disease (DU); 18 with erosive gastritis (EG); and 24 gastroesophageal reflux disease (GERD)]. Allelic variants of cagA, vacA and iceA were identified using the polymerase chain reaction. More than one H. pylori strain was detected in 28 cases (17%), and these were excluded from the statistical analysis. We were unable to confirm an association between iceA status and clinical outcome. There was a strong association between the genotype cagA-positive vacA s1 and PUD. However, logistic regression analysis showed that vacA s1 was the only predictive factor for PUD (OR=4.19; 95% CI 1.95-8.98). The presence of the less virulent strain vacA s2 was related to GERD (OR=8.59; 95% CI 2.85-25.91). Our results support the hypothesis that virulent strains may protect against the development of GERD.     

光肩星天牛种组研究现状

评述了我国光肩星天牛种组种类的外部形态和外生殖器主要鉴别特征、寄主、地理分布、起源及其演化。光肩星天牛主要分布在山西吕粱山、太行山以东的广大平原地区 ,寄主广泛 ,主要有榆、复叶槭、杨、柳、五角枫等。黄斑星天牛主要分布在秦岭以北 ,山西吕粱山、太行山以西的陕甘宁地区 ,向东已扩展到河南、河北 ;主要危害杨树 ,也为害柳、榆。四川星天牛主要分布于秦岭以南的云、贵、川地区 ,主要危害柳树 ;在这里至今还没有发现光肩星天牛和黄斑星天牛。     

Karyotype Analysis of 5 Species of Genus Astragalus

The karyotypes of five species in Astragalus (A. dahuricus DC., A. mongolicus Bunge., A. adsurgens Pall., A. melilotoides Pell., A. huangheensis H. C. Fu., Y. H. Liu) were studied. Among them, the karyotypes of A. dahuricus and A. melilotoides are reported for the first time. While A. melilotoides is tetraploid (2n=4X=32), all the others are found to be diploid (2n= 2X = 16). Based on the comparison of karyotypes, the evolu-tionary order of these 5 species is discussed.     

马铃薯蛋白酶A抑制剂的纯化与性质

采用硫酸铵沉淀、Sephadex G-50和CM柱层析,从马铃薯汁中纯化蛋白酶A（protease A,PrA）抑制剂,并对其部分性质进行研究。蛋白酶A抑制剂为单亚基,相对分子质量为16．71kDa。热稳定性良好,抑制最佳pH范围为5—5．5,最佳反应时间为1．5h,对PrA抑制类型为竞争和非竞争性混合抑制作用。     

Isolation of two new phenolic compounds from the fruit of Chaenomeles speciosa (Sweet) Nakai

Phytochemical research on the anti-inflammatory activities of Chaenomeles speciosa (Sweet) Nakai (Rosaceae) to investigate the main components of 10% ethanol fraction of the crude extract of C. speciosa fruit in an attempt to find bioactive compounds or new compounds from this medicinal plant. The phytochemical investigation succeeded in isolating two new phenolic compounds, specpolyphenol A (1) and specphenoside A (2), together with three known phenyl glycosides (3–5) from the fraction. The structures of the new compounds were deduced from comprehensive spectroscopic analyses including IR, EI-MS, ¹H NMR, ¹³C NMR, DEPT, COSY, HMBC and HMQC. The structures of the three known compounds 3, 4 and 5 were identified by comparison of their spectral data with those reported in the literature.     

Quantitative detection of bisphenol A and bisphenol A diglycidyl ether metabolites in human plasma by liquid chromatography–electrospray mass spectrometry

Due to the ubiquity of epoxy resin compounds and their potential role in increasing the risk for reproductive dysfunction and cancer, the need for an assessment of human exposure is urgent. Therefore, we developed a method for measuring bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) metabolites in human blood samples using high-performance liquid chromatography–electrospray ionization mass spectrometry (LC–MS). Human blood samples were processed using enzymatic deconjugation of the glucuronides followed by a novel sample preparation procedure using a solid-phase-cartridge column. This selective analytical method permits rapid detection of the metabolites, free BPA and a hydrolysis product of BADGE (BADGE-4OH) with detection limits in the low nanogram per milliliter range (0.1 ng ml⁻¹ of BPA and 0.5 ng ml⁻¹ of BADGE-4OH). The sample extraction was achieved by Oasis HLB column on gradient elution. The recoveries of BPA and BADGE-4OH added to human plasma samples were above 70.0% with a standard deviation of less than 5.0%. This selective, sensitive and accurate method will assist in elucidating potential associations between human exposure to epoxy-based compounds and adverse health effects.     

Complexes prepared from protein A and human serum,IgG, or Fcγ fragments: characterization by immunochemical analysis of ultracentrifugation fractions and studies on their interconversion

Summary Protein A of Staphylococcus aureus is an Fc receptor for IgG that has been used as a therapeutic reagent to treat cancer in humans and experimental animals. We used ultracentrifugation combined with analysis of isolated fractions by radioimmunoprecipitation and competitive radioimmunoassay with chicken antibodies that bind free protein A or protein A in complexes but do bind free immunoglobulin reagents to localize and characterize the types of complexes formed with different molar ratios of ¹²⁵I-protein A and human ¹³¹I-IgG alone or in serum, and ¹³¹1-Fc fragments. This approach offers a distinct advantage over direct counting of radioactivity in the fractions because resolution of complexes and free reagents is much improved. With excess ¹³¹I-IgG or ¹³¹1-Fc, all the ¹²⁵I-protein A is present only in complexes that contained 4 molecules of immunoglobulin reagent and 2 molecules of protein A (4:2 complexes), whereas with excess ¹²⁵I-protein A the stoichiometry of the complexes was 1:1. We have also shown the preformed 4:2 and 1:1 complexes will interconvert in the presence of added excess protein A or IgG, respectively, and that fresh IgG will exchange with IgG or Fc in preformed complexes. Because protein A has been found to elute from an immobilized reagent used in serotherapy of human cancer and is present in a large excess of IgG, the 4:2 complexes may play an active role in the tumoricidal or toxic reactions observed.Abbreviations SpA protein A of Staphyloccus aureus - VBS EDTA gel, 0.0055 M veronal buffered saline containing 0.01 M EDTA and 0.1% gelatin, pH 7.4 - PBS 0.01 M phosphate buffered saline, pH 7.4     

Rotational relaxation time of concanavalin A bound to the surface membrane of normal and malignant transformed cells

Fluorescence polarization was used to determine the rotational relaxation time of fluorescein conjugated concanavalin A bound to the surface membrane of normal and malignant cells. The cells used were normal lymphocytes and malignant lymphoma cells, as examples of cells that are in suspension in vivo, and normal and simian virus 40-transformed fibroblasts, as examples of cells that form a solid tissue. The relaxation time of F-concanavalin A² in phosphate-buffered saline, pH 7.2, at 24 °C was 58 nseconds. Under the same conditions, the relaxation times of F-concanavalin A bound to cells were: 70 nseconds for normal lymphocytes, 160 nseconds for malignant lymphoma cells, 120 nseconds for normal fibroblasts and 73 nseconds for simian virus 40-transformed fibroblasts. When cells were treated with trypsin or glutaraldehyde before adding F-concanavalin A, trypsin treatment produced a decrease, whereas glutaraldehyde fixation produced an increase of these values. Inhibition of cap formation of concanavalin A binding sites on normal lymphocytes by treating the cells with sodium azide did not change the rotational relaxation time of concanavalin A bound to the cells. These results indicate that the carbohydrate-containing structures on the cells that bind concanavalin A are mobile. In cells that are in suspension in vivo, malignant transformation is associated with reduction in mobility of these sites. However, in cells that form a solid tissue, malignant transformation is associated with an increase in mobility of these sites. Determination of the rotational relaxation time of fluorescent probes bound to specific sites on cell membranes can thus be used to quantitate receptor mobility in relation to cell behaviour.     

壳二孢属几个新种和新记录种

本文报告了壳二孢属(Ascochyta)新种4个:(木忽)木壳二孢(Ascochyta araliae Sun et Bai),朝鲜槐壳二孢(A.maackiae Sun et Bai),假酸浆壳二孢(A.nicandrae Sun et Bai)和花椒壳二孢(A.zanthoxyli Sun et Bai)。建立了新组合1个,即淡竹壳二孢(A.osmophila(Davis)L(?) et Bai))。此外,报告了国内新记录种19个。新种有拉丁文和中文描述及图。标本保存于沈阳农业大学真菌标本室(MHSAU)。     

中国顶丝藻科新记录Ⅲ

继续报导中国顶丝藻科新记录6种。渐尖旋体藻Audouinella attenuata,球状旋体藻A.globosa,纤细旋体藻A.gracilis,无柄旋体藻A.hypneae,偏枝旋体藻A.secundata,连续旋体藻A.seriata。