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1.
Four flattened Gracilaria species have been reported from Taiwan: G. spinulosa, G. vieillardii, G. textorii and G. punctata, identified based on branching pattern, the presence or absence of spines, and characters that often vary seasonally. Gracilaria spinulosa was originally described from the type locality, Tainan. Species with toothed margins are usually referred to G. “vieillardii”; those with smooth margins to G. “textorii”, and those with smooth margins and dark spots scattered over the blade to G. “punctata”. Molecular analyses show that specimens with marginal teeth cluster in three different groups: a G. “vieillardii” clade, a G. spinulosa clade, and a clade sister to G. spinulosa. An undescribed species comprises the third clade, which is distinguished by its relatively large gonimoblast cells and weakly developed tubular nutritive cells. The three clades can be separated by the character of the tubular nutritive cells, the size of gonimoblast cells and certain vegetative features. Plants with entire margins form a single clade characterized by cystocarps with basal tubular nutritive cells and their absence in the cystocarp cavity. They are nested in the Hydropuntia complex and are referred to as Gracilaria “punctata” here. The records of G. textorii and G. punctata from Taiwan require reinvestigation in comparison with the Japanese species.  相似文献   

2.
Summary We have analyzed cell cycle parameters for theAedes albopictus C7-10 mosquito cell line, which has been systematically developed for somatic cell genetics, expression of transfected genes, and synthesis of hormone-inducible proteins. In rapidly cycling cells, we measured a generation time of 10–12 h. The duration of mitosis (M) was ≤1 h, and the DNA synthesis phase (S) required 6 h. UnlikeDrosophila melanogaster Kc cells, in which the G2 gap is substantially longer than G1, in C7-10 cells G1 and G2 each lasted approximately 2h. In these cells, the duration of both S and G2 was independent of the population doubling time, and the increase in population doubling time as cells approached confluency was due to prolongation of G1. When treated with the insect steroid hormone, 20-hydroxyecdysone, C7-10 mosquito cells complete the cycle in progress before undergoing a reversible arrest.  相似文献   

3.
This study was conducted to compare characteristics of a wheat (Triticum aestivum L.) cell line to those of the maize (Zea mays L.) black Mexican sweet (BMS) cell line and to compare protoplasts isolated from suspension cells of these cell lines. The wheat cell line was established from immature-embryo derived callus of the experimental line ‘ND7532’ and was conditioned for growth in suspension culture. For both cell lines, measurements of packed cell volume (PCV), fresh weight (FW), and dry weight (DW) were taken at 3 day intervals from suspension cultures. Measurements of FW of calluses cultured from suspension cells of both cell lines were taken at 6 day intervals. The morphogenetic potential of the wheat ND7532 cell line was tested in both callus and suspension cultures using media promoting regeneration and/or organogenesis. Growth rates of ND7532 cells in suspension culture were comparable to those of BMS cells. However, relative growth rates of calluses recovered from ND7532 suspension cells were slower than those of calluses recovered from BMS suspension cells. The ND7532 cell line has very limited morphogenetic potential and has been maintained as rapidly growing callus tissue for 11 years. Yields of protoplasts from suspension cells of the two cell lines were comparable, though ND7532 protoplasts were typically smaller. The wheat cell line has is now designated ND7532-NM (nonmorphogenetic) and is available for cellular and molecular biology research.  相似文献   

4.
The taxonomy of three species ofGirella from East Asian waters,G. punctata Gray, 1835,G. leonina (Richardson, 1846) andG. mezina Jordan & Starks, 1907, is reviewed and intraspecific (individual and ontogenic) variations detailed.Girella mezina is characterized by a very wide mouth and thick upper lip, the soft-rayed portion of the anal fin high and round, dorsal profile of the head abruptly slanting in front of the eyes in adults, a transverse yellow band on the body in life, and 3–4 rows of teeth along the outer jaw margins, the central cusp of each tooth being wider than the lateral cusps in adults.Girella punctata is characterized by usually 2 rows of teeth along the outer jaw margins, usually 7 transverse series of scales between the lateral line and median spinous portion of the dorsal fin (TRac), and usually 52–55 pored lateral line scales (LLp). The species is variable in body and caudal fin shape, extent of squamation on the opercular region, and number and position of dark spots on the scales. It also exhibits ontogenetic variation in the number of tooth-rows.Girella leonina is characterized by a conspicuously black opercular flap, essentially a single row of teeth along the outer jaw margins, usually 10–11 TRac and usually 59–64 LLp. Intraspecific variations were evident in the mouth position, scale condition and body color after death, and in the number of pores of cephalic lateral line canals. The holotype ofG. punctata, previously known only from a figure, is described for the first time.Girella melanichthys is synonymized underG. punctata with a lectotype designated for the former.  相似文献   

5.
Gazza dentex (Valenciennes in Cuvier and Valenciennes, 1835), having been synonymized withG. minuta (Bloch, 1795), is redescribed as a valid species.Gazza dentex differs fromG. minuta in having deeper body (43.6–51.4% of standard length [SL] vs. 28.3–46.5% of SL), a broad anterodorsal extension of subocular silvery region, in contact with orbit proximally and distally (vs. a long narrow anterodorsal extension, proximal contact only with orbit), scaled area of anterior dorsolateral suface of body not beyond a vertical through posterior tip of sensory canal on temporal (vs. beyond), distance from posterior margin of temporal to anterior tip of dorsolateral scaled area equal to length of 3–5 anterior pored lateral line scales (vs. length of 1–2.5 anterior pored lateral line scales), some dark narrow wavy bands dorsolaterally on body (vs. some dark broad wavy bands above lateral line and a row of dark spots along lateral line), first interneural inserted deeply between first and second neural spines (vs. inserted shallowly), anterior expansion of first interneural narrow, its margin concave (vs. anterior expansion broad, its margin broadly convex), antrorse extension of first interhemal short, deep, acutely pointed (vs. long, moderately deep, pointed) first to fourth hypurals forming 2 plates (first+second and third-fourth hypurals) (vs. a single plate). The lectotype and three paralectotypes are designated forG. dentex, andG. minuta is redescribed.  相似文献   

6.
The dipteran parasitoids Therobia leonidei and Homotrixa alleni (Tachinidae) use acoustic cues to locate their calling tettigoniid (Ensifera, Orthoptera) hosts. The sexually dimorphic tympanal organs of both fly species are located at the prosternum. For comparison a homologous chordotonal organ in the non-hearing fly Phormia regina, Meigen (Phoridae) is also described. The scolopidial sense organs of the ears have approximately 180 sensory cells in Th. leonidei and 250 cells in H. alleni. Interspecific analysis indicates that the cell number and arrangement might be genus specific in Tachinidae. The mononematic scolopidia, each with one sensory cell, are of different sizes and insert at the tympanal membrane. Large scolopidial units (diameter of sensory cells up to 50 μm) extend longitudinally from the centre of the sensory organ towards the ligament, whereas small units (sensory cell diameter up to 10 μm) are arranged sequentially within the sensory organ. This arrangement is discussed to be a possible basis for frequency discrimination. The ultrastructure of the scolopidia is similar in the hearing and non-hearing flies. In both groups, the majority of scolopales has a diameter from 2 to 2.9 μm, although hearing species have additionally wider scolopales. The homologous chordotonal organ of Ph. regina consists of approximately 55 sensory cells of uniform direction. The data are discussed in comparison to the ears of other Diptera.  相似文献   

7.
Gerres macracanthus Bleeker, 1854, for many years having been explicitly or tentatively synonymized withG. filamentosus Cuvier, 1829, is redescribed as a valid species.Gerres macracanthus differs fromG. filamentosus in lacking vertical rows of dark ovoid spots on the body, having instead only indistinct vertical bands in both subadult and adult stages, in addition to shorter second and third anal fin spines (9.1–13.9% and 10.4–14.4% of standard length [SL] vs. 12.3–19.6% and 11.9–17.3% of SL), fewer ored lateral line scales (41–44 vs. 43–46) and fewer scales between the base of the 5th dorsal fin spine and the lateral line (4–5 vs. 4 1/2–5 1/2), and above and below the lateral line (5 1/2–6 1/2/9 1/2–10 1/2 vs. 6 1/2–7 1/2/10 1/2–11 1/2). AlthoughG. filamentosus has similarly, indistinct vertical bands on the body up to ca. 100 mm SL, specimens over ca. 100 mm SL develop diffuse ovoid spots in each vertical band. Furthermore,G. macracanthus is generally a smaller species, apparently attaining a maximum size of ca. 170 mm SL, compared with ca. 250 mm SL forG. filamentosus. Formerly known from the Philippines, Indonesia, New guinea, India and the Arabian Gulf,G. macracanthus is newly-recorded from Japan, China, the Gulf of Thailand, the Red Sea and South Africa. A lectotype and three paralectotypes are designated forG. macracanthus Bleeker, 1854, in addition to a neotype forG. filamentosus Cuvier, 1829.  相似文献   

8.
Summary A cell line derived from the larval-fat body tissues of the wax moth, Galleria mellonella Linne, was established in MGM-450 medium. The cells grew in suspension and were mainly spherical in shape. Population doubling time was between 1.4 and 1.7 d over a range of 15 to 35°C, and the maximum growth rate was at 25°C. The chromosome number ranged from 70–239, with a mode of 170. The cells were sensitive to 20-hydroxyecdysone, which stimulated their growth and induced morphological changes. The cell line was designated GaMe-LF1.  相似文献   

9.
Gerres methueni Regan, 1920, for many years identified asG. rappi (Barnard, 1927), is redescribed as a senior synonym of the latter species, following examination of two syntypes of the former and comparative material from South Africa and Madagascar.Gerres methueni is characterized by prominent dark stripes along the scale rows above the lateral line and the 4 or 5 rows immediately below it, 5–17 small scales on the preopercular flange, arranged in 1–3 scale row(s) at the corner, 42–44 pored lateral line scales+3–5 additional pored scales on the scaly sheath of the caudal fin base, 41/2–51/2 scales between the fifth dorsal fin spine base and lateral line, and second dorsal fin spine length equal to or slightly shorter than the third dorsal fin spine length.Gerres methueni is currently known from South Africa, southern Mozambique and Madagascar, being endemic in those areas.  相似文献   

10.
Summary Nicotiana tabacum lines carrying maternally inherited resistance to spectinomycin were obtained by selection for green callus in cultures bleached by spectinomycin. Two levels of resistance was found. SPC1 and SPC2 seedlings are resistant to high levels (500 g/ml), SPC23 seedlings are resistant to low levels (50 g/ml) of spectinomycin. Lines SPC2 and SPC23 are derivatives of the SR1 streptomycin-resistant plastome mutant. Spectinomycin resistance is due to mutations in the plastid 16S ribosomal RNA: SPC1, an A to C change at position 1138; SPC2, a C to U change at position 1139; SPC23, a G to A change at position 1333. Mutations similar to those in the SPC1 and SPC2 lines have been previously described, and disrupt a conserved 16S ribosomal RNA stem structure. The mutation in the SPC23 line is the first reported case of a mutation close to the region of the 16S rRNA involved in the formation of the initiation complex. The new mutants provide markers for selecting plastid transformants.  相似文献   

11.
In white spruce (Picea glauca), an improvement of somatic embryo yield and quality can be achieved by applications of dl-buthionine-[S,R]-sulfoximine (BSO), which inhibits the biosynthesis of reduced glutathione (GSH), thereby switching the total glutathione pool towards its oxidized form (GSSG). Applications of BSO almost tripled the embryogenic output of two cell lines by increasing the number of embryos produced by 100 mg−1 tissue from 65 to 154 in the (E)WS1 line and from 59 to 130 in the (E)WS2 line. This increase in embryo number was ascribed to a higher production of morphologically normal embryos with four or more cotyledons (group A embryos), at the expense of group B embryos, characterized by fewer cotyledons. The quality of the embryos produced, estimated by their post-embryonic performance, was also different between treatments. In both cell lines applications of BSO in the maturation medium increased the conversion frequency, i.e. root and shoot emergence, of group A embryos while it enhanced root emergence in group B embryos. Compared to their control counterparts, BSO-treated embryos had normal shoot apical meristems as in their zygotic counterparts. Such meristems were characterized by large apical cells and vacuolated sub-apical cells. They also lacked intercellular spaces, which were present in the apical poles of control embryos where they contributed to cell–cell separation and meristem degradation. Furthermore, storage product accumulation was also improved in the presence of BSO, with protein bodies prevailing over starch. These data show that an oxidized glutathione environment is beneficial for spruce embryo production in vitro.  相似文献   

12.
Five ethanolic extracts from the mycelia of Ganoderma lucidum, G. tsugae, G. oerstedii, G. subamboinense, and G. resinaceum were respectively studied on their anticancerous activities against leukemic HL-60 cell line in vitro. Results showed that all five extracts potently inhibited HL-60 proliferation. The extract from G. lucidum mycelia exerted the highest activity. Annexin V/PI bivariate flow cytometric analysis further revealed that the five extracts significantly induced early apoptosis in HL-60 cells. The results illustrate that not only G. lucidum but also other Ganoderma species can inhibit cancer cells, and their mechanisms are related to induction of apoptosis. __________ Translated from Journal of Shanghai Normal University (Natural Sciences), 2005, 34(2): 77–81 [译自: 上海师范大学学报 (自然科学版), 2005, 34(2): 77–81]  相似文献   

13.
A cytotoxic compound was produced by the marine cyanobacteriumLyngbya sp. Pearl strain in large laboratory-scale batch cultures. Adsorption and fractionation of methanol extracts with reverse phase (C-18) cartridges provided a rapid method for removal of bioassay interference from salts, biopolymers and pigments and concentration of the cytotoxic principles. Cytotoxicity to the murine leukemia cell line P-388 was produced in two cycles coinciding with the initiation of exponential growth and again during the late exponential growth phase. Antiviral activity against influenza virus PR8 was found in extracts prepared from early exponential growth phase cells but antiviral activity was not detected in extracts of mid-log or late-log growth phase cells. These differences in bioactivity suggests that the cytotoxic principles produced during early and late exponential growth may be different compounds. Cytotoxicity assays using murine P-388 leukemia indicates that the semi-pure compound has an IC50 of < 0.25 μg ml−1 to this cell line. P-388 cytotoxicity in cell extracts increased during the late exponential growth phase and the specific yield was estimated at approximately 0.14 mg g−1 (dry cells).  相似文献   

14.
A marine fish cell line from the snout of red spotted grouper Epinephelus akaara, a protogynous hermaphrodite, was established, characterized, and subcultured with more than 60 passages. The grouper snout cell line (GSC) cells multiplied well in Dulbecco’s modified Eagle’s medium (DMEM) medium supplemented with 10% fetal bovine serum. The optimal growth temperature was 25°C, and morphologically the cells were fibroblastic. Chromosome analysis revealed that the GSC cell line has a normal diploid karyotype with . A virus titration study indicated that the cells were susceptible to turbot Scophthalmus Maximus rhabdovirus (SMRV) (108.5 TCID50 ml−1), while the viral titer of frog Rana grylio virus 9807 (RGV9807) reached 103.5 TCID50 ml−1. The infection was confirmed by cytopathic effect (CPE), immunofluorescence, and electron microscopy experiments, which detected the viral particles in the cytoplasm of virus-infected cells, respectively. Further, significant fluorescent signals were observed when the GSC cells were transfected with pEGFP vector DNA, indicating their potential utility for transgenic and genetic manipulation studies.  相似文献   

15.
大型海藻富含多种活性物质,具有抗衰老等生物活性;轮虫是良好的潜在抗衰老研究模式生物。本研究以褶皱臂尾轮虫(Brachionus plicatilis)作为实验对象,研究了不同浓度的大型海藻龙须菜抽提液(0,250,500,750,1000 mg/L)和不同浓度的食物(蛋白核小球藻和普通小球藻)对褶皱臂尾轮虫生命表参数的影响。结果表明:与对照组相比,食物浓度为1.0×10~6个/mL蛋白核小球藻时,不同浓度龙须菜抽提液对轮虫产卵数、平均寿命、净生长率以及世代时间有显著促进效应(P0.05);轮虫平均产卵数及寿命在龙须菜抽提液浓度750 mg/L处达到最高,分别为16只和13.9d(P0.05)。食物浓度为2.0×10~6个/mL普通小球藻时,轮虫平均产卵数和寿命在抽提液浓度为500 mg/L处达到最高,分别为16只和13.6d(P0.05),轮虫平均寿命和净生长率均有显著提高(P0.05)。相同龙须菜抽提液浓度下,食物浓度为1.0×10~6个/mL蛋白核小球藻下轮虫的净生长率、世代时间均显著高于食物浓度为2.0×10~6个/mL蛋白核小球藻培养的轮虫(P0.05);食物浓度为2.0×10~6个/mL时,普通小球藻培养轮虫的净生长率和世代时间均显著高于蛋白核小球藻实验组(P0.05)。交互作用分析显示,龙须菜抽提液与小球藻的交互作用对褶皱臂尾轮虫的内禀增长率有显著影响(P0.05)。研究结果表明,大型海藻龙须菜抽提液对褶皱臂尾轮虫的生长与生殖有促进作用,延长轮虫寿命。  相似文献   

16.
Summary A detailed qualitative and quantitative analysis of the sterol content of normal (auxin and cytokinin requiring) and habituated (auxin and cytokinin independent) sugarbeet callus (Beta vulgaris L.altissima) was made using mass spectrometry with gas chromatography. The total sterol content of the two lines did not differ significantly. Δ7-Sterols were the most important class of sterols in the two sugarbeet callus lines, as in allChenopodiaceae. Elevated levels of Δ8-sterols were found in the habituated callus. These sterols are considered to be badly integrated in the membrane of eucaryotic cells. A partial blocking of Δ87-isomerase is hypothesized in the habituated cell line.  相似文献   

17.
A few individuals with intermediate morphology always appeared in the sympatric distributions of Gentiana straminea and G. siphonantha. These intermediate individuals were hypothesized to be the hybrids of two species after a careful evaluation of their morphological characteristics. To test this hypothesis, sequence comparison of the internal transcribed spacer (ITS) regions of the nuclear ribosomal and trnS (GCU)-trnG (UCC) intergenic spacer region of the chloroplast DNA from Gentiana straminea, G. siphonantha and the putative hybrids was performed. The results suggest that most intermediate individuals were the natural hybrids between G. straminea and G. siphonantha. In addition, we examined the sequence variation among the individuals of both parent species and analyzed the possibility leading to the incongruent identification in some individuals based on morphologic and molecular evidences, respectively. The intraspecific diversification of DNA fragments within both parent species and their high variability in hybrid swarms probably resulted from chloroplast genome recombination and incomplete lineage sorting during the early stages of speciation origin of the parent species. __________ Translated from Acta Botanica Yunnanica, 2007, 29 (1): 91–97 [译自:云南植物研究]  相似文献   

18.
Cytokine expression due to Helicobacter pylori in a tissue culture model   总被引:2,自引:0,他引:2  
Helicobacter pylori, in recent years, has been recognized as the major causative agent in chronic gastritis and peptic ulcer disease in humans. H. pylori is a ubiquitous organism, with at least half of the world’s population infected. Of those individuals with peptic ulcer disease, it is estimated that 90% of cases are caused by H. pylori. Currently, the efficacy of therapies is starting to decline due to increasing resistance rates, especially towards clarithromycin. Due to this, new therapies are needed to combat this bacterium. It is hypothesized that cytokine release (especially interleukin-1β, -6, -8, and TNF-α) due to H. pylori infection and the subsequent influx of inflammatory cells causes a massive release of reactive oxygen species (ROS) during the inflammatory reaction. The ROS then cause the pathologic changes seen in the infected tissues. In this study, human gastric adenocarcinoma cell line ATCC 1739 (a cell line not previously evaluated) was examined for its production of interleukin-1β, -6, -8, and TNF-α when cocultured in a ratio of 10:1 H. pylori to adenocarcinoma cells, to determine its value as a model to demonstrate the inflammatory response. Results from this study indicated that ATCC 1739 cells only reliably produced IL-8 when cocultured with H. pylori and stimulated with TNF-α. The production of IL-1β, IL-6, and TNF-α by the ATCC 1739 cells was no different in H. pylori-exposed cells than non-exposed cells. It was concluded that the ATCC 1739 cell line is not suitable to study the effects of coculture with H. pylori on cytokine production.  相似文献   

19.
Signaling by members of TGF-β superfamily requires the activity of a family of site-specific endopeptidases, known as Subtilisin-like proprotein convertases (SPCs), which cleave these ligands into mature, active forms. To explore the role of SPCs in lateral plate mesoderm (LPM) differentiation in Xenopus, two SPC inhibitors, decanoyl-Arg-Val-Lys-Arg-chloromethylketone (Dec-RVKR-CMK) and hexa-arginine, were injected into the left and right LPM of Xenopus neurulae. Left-side injection caused heart-specific left–right reversal, and this phenotype was rescued by co-injection of mature Nodal protein. In contrast, right-side injection caused left–right reversal of both the heart and gut. Tailbud embryos were less sensitive to SPC inhibitors than neurula embryos. Injection of inhibitors into either side of neurula embryos completely abolished expression of the left-LPM-specific genes, Xnr-1, antivin, and pitx2. SPC1 enzyme (Furin) was injected into the left or right LPM of mid-neurula embryos to determine the effect of enhancing SPC activity. Left-side injection of SPC1 did not cause a significant left–right reversal of the internal organs. However, right-side injection of SPC1 strongly induced the expression of Xnr-1 and pitx2 in the right LPM, and caused 100% left–right reversal of both the heart and gut. These results suggest that moderate level of SPC activity in the right LPM of the neurulae is necessary for proper left–right specification. Taken together, SPC enzymatic activity must be present in both LPMs for expression of the left-handed genes and left–right axis determination of the heart and gut in Xenopus embryos.  相似文献   

20.
中国算盘子属(叶下珠科)一些种的分类学处理   总被引:1,自引:0,他引:1  
姚纲  张连婕  薛彬娥 《广西植物》2017,37(5):547-553
算盘子属(Glochidion J.R.G.Forst.)是叶下珠科(Phyllanthaceae)叶下珠族(Phyllantheae)中一个分类极为困难的类群。基于广泛野外考察与馆藏标本查阅,对中国该属部分物种进行分类学处理。其中,长柱算盘子[G.khasicum(Müll.Arg.)Hook.f.]与倒卵叶算盘子(G.obovatum SieboldZucc.)在中国的分布予以排除,菲岛算盘子[G.philippicum(Cav.)C.B.Rob.]在中国被发现仅分布于台湾地区;G.bodinieri H.Lév.,G.pseudo-obscurum var.glabrum Pamp.与G.pseudo-obscurum var.lanceolatum Pamp.这三个名称被处理为湖北算盘子(G.wilsonii Hutch.)的新异名;G.vaniotii H.Lév.被排除在算盘子属外,并接受为芸香科臭常春(Orixa japonica Thunb.)的异名。另外,对G.khasicum(Müll.Arg.)Hook.f.,G.obovatum SieboldZucc.,G.philippicum(Cav.)C.B.Rob.,G.pseudo-obscurum var.lanceolatum Pamp.及G.wilsonii Hutch.这五个名称进行了后选模式的指定。  相似文献   

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