Meiosis in hybrids between tree coffees (C. liberica,C. dewevrei) and Nandi coffee (C. eugenioides)

Meiotic behaviour of hybrids between Coffea dewevrei var. excelsa and C. eugenioides, and between C. liberica and C. eugenioides, and of open pollinated progeny of these hybrids reveals a close genome relationship in spite of striking morphological differences and distinct geographic separation. In the cross C. dewevrei excelsa X C. eugenioides several maternal types occurred, attributed to parthenogenesis. The hybrids are self-sterile and set few seeds on open pollination, again partly involving parthenogenesis, and participation of some unreduced gametes in hybridization.Subdivision of the section Eucoffea into different subsections (C. dewevrei and C. liberica belonging to subsection Pachycoffea, C. eugenioides to Erythrocoffea) has no cytological basis.     

Morphology and anatomy of male cones of Pseudotaxus chienii (W.C. Cheng) W.C. Cheng (Taxaceae)

Results of the present study indicate that male cones of Pseudotaxus chienii are representing inflorescences with strongly reduced flowers. The results fit quite well with investigations showing that sporangiophores of Taxus and also of Pseudotaxus comply with reduced flowers. The only difference between male cones in Taxus and Pseudotaxus is the absence of pherophylls in Taxus. Furthermore our results complete a transition series beginning with Cephalotaxus going on to Pseudotaxus and ending with Taxus and Torreya. In this progression Pseudotaxus can be regarded as an intermediate link between the inflorescences of Cephalotaxus and the simple, unbranched cones of Taxus. The entire transition series shows that sporophyll-like sporangiophores can be derived by reduction of lateral cones. There is however no sign that a similar process has occurred in other conifer groups.     

Determination of isozymes of phosphoglycerate-mutase (E.C.2.7.5.3) and enolase (E.C.4.2.1.11) in human erythrocytes.

525 human hemolysates were tested for the isozymic patterns of phosphoglycerate mutase and enolase. Genetic models for interpreting the pherograms are suggested.     

Flavonoids and anthraquinones from Murraya tetramera C. C. Huang (Rutaceae)

Phytochemical investigation of Murraya tetramera C. C. Huang led to the isolation of ten flavonoids (1−10) and three anthraquinones (11−13). Their structures were determined on the basis of MS, NMR, specific optical rotation, and CD spectroscopic data analysis, and by comparison of the obtained data with those reported in the literature. This is the first report for the occurrence of compounds 2, 4–7, and 11–13 in the Murraya species, and all the compounds were isolated from M. tetramera for the first time with the exception of compound 3. The chemotaxonomic significance of these compounds was also discussed.     

Elongation of (omega-14C)oleic acid and (omega-14C)nervonic acid.

During feeding experiments with [omega-14C]oleic acid and [omega-14c]nervonic acid to adult rats, 14C-labelled C26, C28 and C30 fatty acids were recovered from the intestinal mucosa, liver, plasma, kidney and stools. The structures of these fatty acids were determined by g.l.c., radio-g.l.c. and mass spectrometry. The Schmidt and Ginger degradation methods indicated that most of the 14C found in these extra-long fatty acids remained in the omega position. These radioactive extra-long fatty acids were found mainly in the polar lipids of rats killed 3 or 15 h after being fed on labelled oleic acid or nervonic acid. Rats killed 63 h later yielded only traces of these extra-long fatty acids. When the rats were given antibiotics or received the same radioactive fatty acids by intravenous injection, the labelled extra-long fatty acids could not be detected in any of the tissues. We conclude that they were probably synthesized by elongation of oleic acid and nervonic acid by intestinal micro-organisms (probably yeasts) and then absorbed by the intestinal mucosa.     

First determination of the isozyme patterns of phosphoglycerate mutases (E.C.2.7.5.3) and phosphoglycerate kinases (E.C.2.7.2.3) in human tissues.

We present in this paper the first report about identification of several fractions of phosphoglycerate mutase (PGlyM) activity using starch gel electrophoresis and two different buffer systems. A typical muscle form of PGlyM was detected. It is also shown that isozymes of phosphoglycerate kinase (PGK) can be separated through the buffer system used by Spencer et al; (1964) for the phosphogluco mutase.     

Calyptocarpus vialis and C. wendlandii (Compositae)

RecentlyCalyptocarpus has been considered monotypic, butC. vialis of eastern Mexico proves to be distinct fromC. wendlandii of Central America. A key to these and to the often-misidentifiedSynedrella nodiflora is provided, and all three species are illustrated.     

Calorimetric studies of the effects of cholesterol on the phase transition of C(18):C(10) phosphatidylcholine.

Differential scanning calorimetry (DSC) has been employed to study the effects of cholesterol on the phase transition of C(18):C(10) phosphatidylcholine (C(18):C(10)PC). C(18):C(10)PC is an asymmetric mixed-chain phosphatidylcholine known to form mixed-interdigitated structures below the transition temperature and form partially interdigitated lipid bilayers above the transition. Three types of samples were used. The treated sample is the lipid dispersion that had undergone three freeze-thaw cycles and stored at 4 degrees C for more than 48 h. The untreated sample was made by vortexing the dry lipid in 50 mM KCl, without the above-mentioned pretreatment. The cold-treated sample was prepared by incubating the treated sample at -20 degrees C for 15 d. There is no apparent difference in the DSC curves between the treated and cold-treated samples. The data derived from the treated samples seem to be more reproducible. The DSC curves between the cholesterol/C(18):C(10)PC and cholesterol/symmetric diacylphosphatidylcholine mixtures are different in three aspects: overall appearance, the cholesterol dependence of delta H, and the effect of cholesterol on the maximal transition temperature Tm, the onset temperature To, and the completion temperature Tc. for both the treated and untreated samples, the total enthalpy change delta H of the phase transition of C(18):C(10)PC decreases with increasing cholesterol content, approaching zero at approximately 25 mol%. This level is lower than the total enthalpy changes reported previously for the cholesterol/symmetric diacylphosphatidylcholine mixtures. Both the heating and cooling thermograms show that Tm, To, and Tc decrease with increasing cholesterol content. The decreasing rates of these temperatures with cholesterol are in the neighborhood of -0.24 degree per mol% of cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)     

白豆杉的叶绿体基因组结构与系统进化分析

以红豆杉科单种属植物白豆杉(Pseudotaxus chienii(W.C.Cheng)W.C.Cheng)为材料,进行叶绿体全基因组测序,并对其基因含量、结构及重复序列进行分析.结果显示:白豆杉叶绿体基因组不包含典型的反向重复区,基因组全长为130427 bp,共编码116个基因,包含83个蛋白编码基因、4个rRNA...     

On the classification of Calligonum juochiangense and C. pumilum (Polygonaceae)

After observing specimens of Calligonum pumilum Losinsk. and C. juochiangense Y. X. Liou in both the field and in herbarium collections, it was found that the morphological characters of these two species are quite different, especially with respect of the twisted direction of fruit ribs, number of bristle rows along each rib, rigidity and degree of interweaving of bristles, as well as their geographic distribution. Therefore, it is concluded that C. pumilum and C. juochiangense should be accepted as two independent species.     

The determination of the red cell isoenzymes 6-phosphogluconate dehydrogenase (E.C.1.1.1.44) and acid phosphatase (E.C.3.1.3.2) by means of agarosegel thinlayer electrophoresis (author's transl)

Methods for the determination of the red cell isoenzymes 6-PGD and acP by means of agarosegel thinlayer electrophoresis are referred. Using these relatively simple techniques, results can be obtained after at least two hours. The quality of separation in both systems is higher than that obtained after starch gel electrophoresis.