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A survey of translocation of photoassimilates in 13 genera of Laminariales is presented. All showed long-distance transport of 14C-labeled products from mature source tissue to meristematic sinks (haptera and intercalary growing regions). In plants with several laminae forming one frond, older laminae may provide assimilates for the growth of younger ones, and in Macrocystis spp., where fronds of different ages and developmental stage arise from a common holdfast, mature fronds initiate and support new fronds. Translocation velocities vary from species to species but are in the range of 55 to 570 mm/h. The results strongly support the hypothesis that Laminariales in general have an effective translocation system, on which their thallus growth depends.

Midribs of the perennial red alga Delesseria sanguinea (Hudson) Lamouroux are able to develop small new blades after several months in continuous darkness. Dark-grown blades contained phycobiliproteins, only traces of chlorophyll a, and were unable to evolve O2 when first illuminated. Light treated ‘etiolated’ blades synthesized increasing quantities of chlorophyll and in parallel, an increasing photosynthetic oxygen production was recorded. Plastids of dark-grown blades revealed a different arrangement of thylakoids compared with light-grown plants. Phycobiliproteins in ‘etiolated’ blades were not organized in phycobilisomes.

Freshly collected pieces of the hermatypic coral Acropora cf. scandens containing dinoflagellate endosymbionts (presumably Gymnodinium microadriaticum) were allowed to assimilated 14C from H14CO3-in the light and in the dark. Time-dependent carbon uptake resulted in intense 14C-labelling of ethanol-soluble as well as of insoluble assimilates. About forty 14C-labelled assimilates have been identified. Polymeric (ethanol-insoluble) compounds achieve about 30% of total radiocarbon incorporation after 60 min incubation. Kinetics of 14C-labelling of single assimilates are analyzed. Percentages of typical photosynthates in the soluble fraction undergo characteristic time-dependent changes. Lipids proved to be the main accumulation products of carbon assimilation by incorporating more than 50% of 14C after 60 min photosynthesis. The data indicate that low-molecular weight photosynthates such as 14C-glycerol and 14C-glucose are rapidly converted to constituents of the polymeric fraction(s) of the coral. Besides peptides, polysaccharides, and lipophilic substances, considerable amounts of 14C are confined to skeletal CaCO3 of the coral. The results are discussed with respect to trophic and metabolic interrelationships between the autotrophic dinoflagellates and the A. cf. scandens tissues.

To date, the presequence of the mitochondrial beta-subunit of ATPase from tobacco is the only signal sequence that has been shown to target a foreign protein into plant mitochondria in vivo. Here we report that the presequence of a yeast mitochondrial protein directs bacterial beta-glucuronidase (GUS) specifically into the mitochondrial compartment of transgenic tobacco plants. Fusions between the presequence of the mitochondrial tryptophanyl-tRNA-synthetase gene from yeast and the GUS gene have been introduced into tobacco plants and yeast cells. In both systems, proteins containing the complete yeast mitochondrial presequence are efficiently imported in the mitochondria. Measurements of GUS activity in different subcellular fractions indicate that there is no substantial misrouting of the chimeric proteins in plant cells. In vitro synthesized GUS fusion proteins have a higher molecular weight than those found inside yeast and tobacco mitochondria, suggesting a processing of the precursors during import. Interestingly, fusion proteins translocated across the mitochondrial membranes of tobacco have the same size as those that are imported into yeast mitochondria. We conclude that the processing enzyme in plant mitochondria may recognize a proximate or even the same cleavage site within the mitochondrial tryptophanyl-tRNA-synthetase presequence as the matrix protease from yeast.

The ionization induced in organic vapours added to argon-methane proportional chamber gas by an UV laser emitting at a wavelength of 266 nm has been studied. At concentrations of 30–70 ppm and laser energy densities of 1 μJ/mm 2 , ionization densities of 10 3 electrons per mm 3 are obtained. These vapours are adsorbed by the chamber walls and difficult to remove. Procedures for gas cleaning are given.

[(Cu6H5)4P]2(NH4)[Cu3(S4)3] · 2CH3OH (1a) konnte durch Reaktion von Cu(H3COO)2 · H2O mit einer Polysulfid-Losung rein dargestellt werden. Das Anion [Cu3(S4)3]3−(1) besteht aus einem zentralem Cu3S3 — Sechsring — und drei CuS4 — Funfring — Systemen. Die Rontgenstrukturanalyse ergab folgende Resultate fur 1a: Raumgruppe P21/c, a = 2317,4(7), b = 1458,4(4), c = 1843,1(5) pm, β = 108,68(2)°, V = 5901,0 106 pm3, Z = 4; R = 0,101 fur 3817 unabhangige Reflexe (Fo > 3,92σ(Fo)). 1a wurde weiterhin Raman-spektroskopisch charakterisiert. [Cu3(S4)3]3−, a New Condensed Inorganic Ring System. Comparison with the Structures of Other Polysulfido Clusters of Copper By reaction of Cu(CH3COO)2 · H2O with a polysulfide solution [(C6H5)4P]2(NH4)-[Cu3(S4)3] · 2CH3OH (1a) could be obtained in a pure form. The anion [Cu3(S4)3]3− (1) consists of a central Cu3S3 ring and three CuS4 rings. An X-ray structure analysis yields the following results for 1a: Space group P21/c, a = 2317.4(7), b = 1458.4(4), C = 1843. 1(5) pm, β = 108.68(2)°, V = 5901.0 106 pm3, Z = 4; R = 0.101 for 3817 independent reflections (Fo > 3.92° (Fo)). 1a was also characterized by its Raman spectrum.

The first unambiguous observation of a “bisected” primary cyclopropylcarbinyl cation is reported. This cation was formed by ring contraction of a C 8 tricyclic framework. Although totally unexpected from a bond energy-steric strain standpoint, this observation underlines the large resonance stability associated uith “bisected” cyclopropylcarbinyl cations.

The mitochondrial genome of four Epilobium species has been characterized by restriction analysis and hybridizations with gene probes from Oenothera. Mitochondrial DNA of Epilobium has a complex restriction fragment pattern and an estimated size of about 320 kb. All species exhibit specific restriction patterns. Plasmid-like DNA molecules of 0.3 kb to 1.2 kb are found in preparations of undigested nucleic acids of mitochondria from E. montanum, E. watsonii, and E. lanceolatum. In contrast, the mitochondria of E. hirsutum contain double-stranded RNAs of 2.7 kb. The location of the genes for cytochrome c oxidase subunits I and III on the mitochondrial DNA seems to be conserved in those species analyzed. However, the genes for subunit II of this complex, and for the alpha subunit of ATPase, are located on different restriction fragments in the mitochondrial genomes of certain species. The location of the COX II gene on different BamHI fragments in E. watsonii and E. lanceolatum has been used for the analysis of mitochondrial inheritance in reciprocal hybrids. Like the plastids, mitochondria are inherited maternally in Epilobium.

Es wird uber eine einfache Darstellungsmoglichkeit von Metall-Schwefel-Clustern aus einfachen Metall-Salzen und H2S in Losung berichtet und zwar fur die Systeme Cum+/H2S und Fen+/H2S. Die Verbindungen R2(NH4)[Cu3S12], R2[Cu4S12] · CH3CN, R2[Cu4S12,8], R2[Fe2S2(S5)2], R2[Fe4S4Br4], R2[Fe4S4Br2Cl2], R2[Fe4S4Cl4], R2[Fe2S2Cl4] (R = PPh4) und [Fe(DMF)6][Fe2S2Cl4] wurden spektroskopisch (IR, Raman, Fe-Mosbauer) sowie durch vollstandige Kristallstrukturanalyse charakterisiert (mit Ausnahme von R2[Fe2S2(S5)2]). (PPh4)2(NH4)[Cu4S12]: P1, a = 1266,0(5), b = 1 489,6(6), c = 1 493,6(6) pm, α = 74,72(3), β = 86,40(3), γ = 77,52(3)°, V = 2 652,9 · 106 pm3, Z = 2; R = 0,057 fur 8377 unabhangige Reflexe (Fo > 3,92 σ(Fo)). (PPh4)2(NH4)[Cu4S12] · CH3CN: P1, a = 1 062,2(3), b = 1 336,2(4), c = 2 137,8(6) pm, α = 102,42(2), β = 90,60(2), γ = 110,16(2)°, V = 2 769,8 · 106 pm3, Z = 2; R = 0,076 fur 4312 unabhangige Reflexe (Fo > 3,92 σ(Fo)). (PPh4)2[Cu4S12,8]: P21/n, a = 1 245,2(8), b = 1 306,9(10), c = 3348,7(22) pm, β = 98,90(5°), V = 5383,9 · 106 pm3, Z = 4; R = 0,094 fur 4814 unabhangige Reflexe (Fo > 3,92 σ(Fo)). (PPh4)2[Fe4S4Br4]: C2/c, a = 1585,8(6), b = 1440,6(4), c = 2419,7(9) pm, β = 112,74(3)°, V = 5 098,1 · 106 pm3, Z = 4; R = 0,068 fur 3 247 unabhangige Reflexe (Fo > 3,92 σ(Fo)). (PPh4)2[Fe4S4Br2Cl2]: C2/c, a = 1592,3(3), b = 1432,9(3), c = 2325,0(5) pm, β = 106,43(2)°, V = 5 088,1 · 106 pm3, Z = 4; R = 0,084 fur 1982 unabhangige Reflexe (Fo > 3,92 σ(Fo)). (PPh4)2[Fe4S4Cl4]: C2/c, a = 1593,9(3), b = 1420,8(2), c = 2316,9(4) pm, β = 106,65(1)°, V = 5026,9 · 106 pm3, Z = 4; R = 0,069 fur 3 902 unabhangige Reflexe (Fo > 3,92 σ(Fo)). [Fe(DMF)6][Fe2S2Cl4]: P1, a = 923,5(4), b = 941,4(4), c = 1123,9(5) pm, α = 75,29(4), β = 71,17(3), γ = 87,27(4)°, V = 893,9 · 106 pm3, Z = 1; R = 0,067 fur 1832 unabhangige Reflexe (Fo > 3,92 σ(Fo)). Preparation of Metal-Sulfur-Clusters by Simple Reaction of Metal-Salts with H2S: R2(NH4) [Cu3S12], R2[Cu4S12] · CH3CN, R2[Cu4S12,8], R2[Fe2S2(S5)2], R2[Fe4S4Br4], R2[Fe4S4Br2Cl2], R2[Fe4S4Cl4], R2[Fe2S2Cl4] (R = PPh4) and [Fe(DMF)6][Fe2S2Cl4] Simple preparation methods for metal sulfur clusters from simple metal salts and H2S in solution are reported (for the systems Cum+/H2S and Fen+/H2S). The compounds R2(NH4)[Cu3S12], R2[Cu4S12] · CH3CN, R2[Cu4S12,8], R2[Fe2S2(S5)2], R2[Fe4S4Br4], R2[Fe4S4Br2Cl2], R2[Fe4S4Cl4], R2[Fe2S2Cl4] (R = PPh4) and [Fe(DMF)6][Fe2S2Cl4] were characterized spectroscopically (IR, Raman, Fe-Mossbauer) and by complete crystal structure analyses (except R2[Fe2S2(S5)2] and R2[Fe2S2Cl4]). For structural data see Inhaltsubersicht.

Prior to long-distance assimilate transport in the blades of Laminariales, photoassimilate from the meristoderm (source tissue) must first be transferred across the cortex before it can be loaded into the sieve elements. This radial assimilate transfer seems to be a symplastic parenchyma transport. The wings of Alaria tenuifolia Setchell are only a few cell layers thick and reveal a continuous cell system interconnecting the meristoderm with the sieve elements. This cell system probably provides an uninterrupted route for the symplastic transverse assimilate transfer and loading. The tissue topography of the wings, the anatomy of the composing cell types, and the micromorphology of the cellular network channelling assimilate to the sieve element system are described. The anatomical results are discussed with regard to the transport physiology of Laminariales in general and the possible mode of sieve element loading.

Reciprocal differences for male sterility, dwarfism and morphological traits have been studied in intraand interspecific crosses of five Epilobium species. Male sterility occurred in two interspecific hybrids with E. montanum as the male parent while dwarfism has been found to varying degrees in three interspecific crosses with E. watsonni. In contrast to transient differences in plant height and leaf morphology in reciprocal hybrids of the cross between E. hirsutum and E. parviflorum, male sterility and dwarfism persistently occur as reciprocally different traits which may be influenced by determinants of the cytoplasm. The molecular characterization of the plastid DNA of the parental lines and the F1 hybrids indicate that the plastome of male sterile and dwarf plants is identical to that of the female parents. Furthermore, in spite of these developmental disturbances, the expression of plastid genes coding for polypeptides of thylakoid-membrane complexes is unchanged. Thus, it seems unlikely that the genetic compartement of the plastids is responsible for the expression of the male sterile or the dwarfed phenotype.

Studies on Sulphochlorination of Paraffins. VII. Studies on the Chlorination of Individual Alkane Sulphochlorides The products of the chlorination of individual C2–C6 alkane sulphochlorides were studied by means of 13C-n.m.r. spectroscopy. In no case a geminal chloro sulphochloride could be found, and only in very few cases chlorination at vicinal CH-bonds took place. As in the sulphochlorination of alkane sulphochlorides the CH-bonds geminal and vicinal to the sulphochloride group are strongly descativated. The results of 13C-n.m.r. analyses were confirmed by the results of gaschromatography of the sulphonic acid dimethyl amides, formed by the reaction of the chlorination mixtures with dimethyl amine.

Interspecific hybrids of various Epilobium species have been produced in order to analyse plastid inheritance using restriction fragment polymorphisms of plastid DNA as markers. This analysis reveals that interspecific hybrids exhibit only the fragment pattern of the maternal plastome. Southern hybridization experiments using cloned species-specific plastid DNA fragments as markers confirm the maternal type of plastid inheritance in Epilobium, while providing at least a tenfold increase of sensitivity to detect restriction polymorphisms. Within the limit of detection even young seedlings contain no plastid DNA from the paternal parent. However, investigations of plastomes of large populations have provided evidence that a very low frequency of paternal plastid transmission can occur. Thus, the mechanism which ensures the elimination of paternal plastids is not 100% efficient. This suggestion is also supported by intraspecific reciprocal crosses between plants carrying mutant white and normal green plastids. While the offspring usually exhibit the maternal plastid type, a few cases indicate an apparent paternal plastid transmission.

From exposures of the CDHS detector at the CERN SPS we have obtained 367μ + μ − events in neutrino beams and 73μ + μ + events in an antineutrino beam. The magnitude of a prompt like-sign signal has been controversial in the past and moreover could not be explained by known production mechanisms. A critical discussion of the experimental situation is given. We have tried to reduce the systematic uncertainties of previous experiments and to get more information on the dependence of the signal with energy and the muon momentum cut-off. This experiment yields a signal of 2.8σ (2.4σ) of prompt like-sign dimuon events in the case of neutrinos (antineutrinos). The rate to charged current events is of the order of 10−4 forp μ 100 GeV. The prompt signal has all the properties expected from the production and decay of charm-anticharm events. The magnitude, however, is substantially higher then the prediction of perturbative QCD but lower than some other experiments.

When the marine opisthobranchiate slug Hermaea bifida Mont. is incubated in a H14CO 3 - -seawater medium in the light, a considerable net gain of 14C-assimilates is observed. Electron microscopic control provided evidence that this 14C-fixation is due to photosynthesis by chloroplasts (=rhodoplasts) endosymbiotic in the cells of the digestive gland of the slug. After thin-layer chromatographic analysis various 14C-labelled photosynthates could be traced. The assimilate pattern of the rhodoplasts is compared with that of the marine red alga Griffithsia flosculosa (Ellis) Batt., from which the plastids are acquired by feeding. The nutritional relationship of this endosymbiosis is discussed, with emphasis on the occurrence of functional chloroplast endosymbioses among the eolidiform species of the Sacoglossa.

Reaction of cytoplasmic streaming inTradescantia staminal hairs to microfilament and microtubule specific inhibitors, applied either by conventional immersion or by microinjection, indicates that both the actin-myosin and the microtubule system may be involved in driving the particle stream. Cytoplasmic streaming was stopped at relatively high drug concentrations when the cells were immersed in the inhibitor solution. Microinjection of defined concentrations of inhibitor into single, selected cells were effective at concentrations at least two orders of magnitude lower. Further reduction of inhibitor concentrations, however, enhanced streaming up to 100%. When a mixture of cytochalasin D and oryzalin were injected at concentrations that had previously been shown to enhance particle movement, very efficient inhibition occurred and streaming rapidly stopped. Adjacent cells on both sides of the injected cell were also affected: within a few minutes of the injection of microfilament inhibitors the basal cell reacted, followed slightly later by the apical one; microtubule inhibitors caused a reaction in the apical cell earlier than in the basal cell. The results are discussed with respect to the involvement of actin and myosin microfilaments, as well as microtubules, as force generating systems of particle movement.

Plastid DNAs of ten different Epilobium species from four continents have been analysed using the restriction endonucleases BamHI, BglI, BglII, EcoRI, PstI, PvuII and SalI. With respect to the position of cleavage sites of those enzymes, each species has a specific plastome. Fragment patterns of different species from the same continent show a higher degree of similarity than those from different continents. Physical maps of the circular plastid DNA molecule have been constructed for each of the ten species by localising the cleavage sites of the enzymes BglI, PvuII and SalI. As in most other higher plants, the plastid DNA of Epilobium is segmentally organized into two inverted repeats separated by a large and a small single copy region. In heterologous hybridization experiments using radioactively labelled gene probes, the positions of structural genes coding for the rRNAs and for seven polypeptides have been determined. In contrast to its closest relative, Oenothera, the gene arrangement of Epilobium plastomes has the same order as in spinach. This indicates that changes in gene arrangement may be genus-specific and not the result of one or several events affecting all members of a plant family.

Die diamagnetischen (Ausnahme 1a) Verbindungen (PPh4)2[Fe(WS4)2(NO)] (1a), (PPh4)2[Fe(WS4)(NO)2] (2a), (PPh4)2[Co(WS4)2(NO)] (3a) und (PPh4)[Co(WS4)(NO)2] (4a) wurden durch UV/VIS- und IR-Spektroskopie, magnetische Messungen sowie durch vollstandige Rontgenstrukturanalyse charakterisiert. 1 a: P1, a = 912,3(2), b = 1052,7(2) c = 1340,7(3) pm, α = 87,16(2), β = 84,15(2), γ = 84,90(2)°, V = 1274,7 · 106 pm3, Z = 1; R = 0,088 fur 2284 unabhangige Reflexe (F0 > 3,92 σ(F0)); 2a: P1, a = 974,1(2), b = 1278,6(3), c = 1986,2(4) pm, α = 103,71(2), β = 104,94(2), γ = 95,55(2)°, V = 2289,0 · 106 pm3, Z = 2; R = 0,075 fur 4490 unabhangige Reflexe (F0 > 3,92 σ(F0)); 3a: P1, a = 908,8(9), b = 1049,4(10), c = 1342,5(14) pm, α = 87,21(8), β = 83,99(8), γ = 85,26(8)°, V = 1267,9 · 106 pm3, Z = 1; R = 0,074 fur 3145 unabhangige Reflexe (F0 > 3,92 σ(F0)); 4a: P1, a = 957,2(2), b = 1074,6(3), c = 1394,8(3) pm, α = 100,71(2), β = 90,55(3), γ = 93,68(2)°, V = 1406,5 · 106 pm3, Z = 2; R = 0,068 fur 3599 unabhangige Reflexe (F0 > 3,92 σ(F0)). Fur (NEt4)[Co(MoO2S2)(NO)2] werden fruher nicht mitgeteilte kristallographische Daten angegeben. Heterometal Nitrosyl Complexes with Remarkable Electronic Structure: Preparation and Crystal Structure of R2[Fe(WS4)2(NO)], R2[Fe(WS4)(NO)2], R2[Co(WS4)2(NO)], and R[Co(WS4)(NO)2] (R = PPh4) The diamagnetic (exception 1a) compounds (PPh4)2[Fe(WS4)2(NO)] (1a), PPh4)2[Fe(WS4)(NO)2] (2a), (PPh4)2[Co(WS4)2(NO)] (3a), and (PPh4)[Co(WS4)(NO)2] (4a) were characterized by UV/VIS and IR spectroscopy, magnetic measurements and by complete X-ray structure analyses. For crystal data see Inhaltsubersicht. In addition unpublished crystallographic data for (NEt4)[Co(MoO2S2)(NO)2] are given.

The large kelp Macrocystis integrifolia and Nereocystis luetkeana off the coast of British Columbia have light saturation points at about 200 foot candles (1 foot candle = 10.76391 lx); however, photosynthetic rates remain unimpeded through mugh higher light intensities, up to 7000 foot candles. Short-term labelling experiments indicate that the Calvin cycle is operational in these plants, but, in addition, and particularly in the young growing parts, relatively high activities of phosphoenolpyruvate carboxykinase (PEP-CK)and correspondingly high rates of 14C fixation in the dark are observed. In older, mature parts, the activity of PEP-CK as well as the ability for light-independent 14C assimilation are lower. These observations are supported by data from a variety of other Pacific Laminariales. Pulse–chase experiments in the light and in the dark reveal characteristic differences between young and mature parts of the fronds: apart from qualitative difference in the soluble fraction of assimilates, the young parts show a significantly large proportion of radiocarbon confined to the ethanol-insoluble fraction.

We have investigated the sequential stages of microgametogenesis by electron microscopy, to determine the basis of maternal inheritance of plastids in Epilobium. The development of both the vegetative and generative cells has been followed using a semi-artificial growth system for pollen tubes. The generative cells inside the pollen grain contains numerous mitochondria, 5–8 proplastids, and, in contrast to the vegetative cytoplasm, only a few vacuoles. When the generative cell has divided into the two sperm cells inside the pollen tube, small vesicles deriving from dicytosome cisternae become abundant. These vesicles appear to form vacuoles by fusion which then contain remnants of fibrillar, globular or membranaceous material. It is suggested that this material derives from proplastids as the proplastids disappear either before or shortly after the generative cell has divided, concurrently with the appearance of the ‘remnants’ in the vacuoles. The mitochondria of the sperm cells remain intact.

Using highly enriched samples of the zirconium isotopes 90, 92, 94, and 96 the isotope shift in the Zr-I spectrum has been measured with the aid of a photoelectrically recording Fabry-Perot spectrometer. Both mass-dependent and nuclear-volume effects were found to contribute to the observed shifts. The nuclear-volume dependent part of the measured shifts has been determined; the relative position of the isotopes caused by this part isΔνV(90−92):ΔνV(92−94):ΔνV(94−96)=1:(0.70±0.08):(0.54±0.06). The experimental isotope-shift constantsβCexp are (90–92)∶44·1±5·1; (92–94)∶30·9±5·4; (94–96)∶23·8±5·0 mK.

A process to manufacture titanium-boron composites has been demonstrated with a 30-filament tape in which reaction is controlled to a few hundred Angstroms of boride. This tape has good properties—indicating efficient use of the boron reinforcement—combined with good reproducibility (coefficient of variation of tensile properties approaches 2 percent). Simulated exposures confirm predictions that many thousands of hours of service life are possible at temperatures up to 1200 F. In addition, creep, fatigue, compression, cross tensile, and shear properties are presented. Application of this metal matrix tape to gas turbines is discussed. It is shown that the advantages of boron-reinforced plastic tapes in manufacturing are combined with the advantages of a metal matrix for shear load transfer, cross tensile strength, erosion resistance, and high-temperature performance.

A mixed oxide (U,Pu)O2 containing five elements (Mo, Ru, Ba, Zr, and Ce) representative of the fission product yield at 150 000 MWd/t has undergone a short-term irradiation to obtain the characteri...

Translocation of 14C-labelled assimilates in Laminaria hyperborea and L. saccharina is strictly basipetal within the thallus. The lowermost 20 cm of the frond accumulates 71% (L. hyperborea) or 63% (L. saccharina) of the basipetallymoving translocate after a period of 96 h from initial feeding with NaH14CO3. Whereas translocation was found to occur at all seasons in L. saccharina, which grows throughout the year, no translocation of newly synthesized photosynthate occurred in L. hyperborea in October, when no frond enlargement takes place, nor in January, when the new fond occurs as a tiny outgrowth. In L. hyperborea, organic material, assimilated by the old frond during the period of rapid growth, is exported at the rate of 0.5 mg C · dm-2 · h-1. In L. saccharina, 14 to 18 cm frond length are necessary for an elongation rate of the growing zone, situated in lowermost 10 cm of the frond, of 1 cm per week. The significance of translocation in the two Laminaria species is demonstrated by comparison of export rates with growth rates measured in situ and in the laboratory.

Determination par diffraction RX des structures cristallines de (PPh 4 ) 2 [Ag 2 (S 9 ) 2 ], (PPh 4 ) [AgS 9 ] et (PPh 4 )(NH 4 ) S 7 .CH 3 CN

Isolement de nouvelles especes cycliques et polycycliques a partir de solutions de polysulfures. Etude RX

Numerous species of Meriones have been incriminated as natural reservoir hosts of Leishmania major in Mongolia, Soviet Asia, Afghanistan, the Middle East, and North Africa. However, little is known about the immunological response or course of infection in these small rodents. In this study, 40 commercially obtained inbred Meriones unguiculatus were divided into equal groups and injected in the right hind footpad with various doses of L. major promastigotes or with medium only. At regular intervals, blood was collected from the animals for subsequent evaluation of the kinetics of anti-L. major serum antibody production. Footpad lesions were measured periodically for 13 wk, beginning just before infection. The humoral response to infection and the course and severity of disease were dose related. However, metastasis lymph nodes, liver, spleen, and secondary cutaneous sites occurred at each of the doses tested.

In the first part of the paper is reported on differential-therapeutic experiences in the hospital treatment of 307 alcoholics with disulfiram R, Lithium R and Apomorphine R as monotherapy as well as in combined application. Our investigations show that neither lithium R nor apomorphine R have ascertained advantages to the monotherapy with Disulfiram R. An improvement of the still unsatisfactory number of success is to be achieved in the first place by an optimization of the after-care by means of a close sociotherapeutic and if necessary psychotherapeutic care, possibly in special outpatient departments. In the second part of the paper is reported on first experiences.

A new method of investigating the efficacy of regional thermotherapy in subcutaneous xenografts of nude mice is reported. The use of high frequency hyperthermia was well tolerated by the sensitive animals and allowed an exact continuous temperature measurement in different tumor regions. The interstitial procedure in this model could be the best approach for later clinical use in urology, e.g. for prostate treatment and is an alternative to the transrectal hyperthermia application.

Mitochondrial DNA (mtDNA) and transcriptional patterns of mitochondrial genes have been examined in dwarf, normal, fertile and male sterile Epilobium hybrids. No alterations or rearrangements of mitochondrial DNA could be detected in the developmentally disturbed hybrids. They exhibit restriction patterns of mtDNA that correspond exactly to those of their female parents. However, the transcription of at least one mitochondrial gene is significantly altered in the male sterile hybrid E. hirsutum x montanum. In normal plants, one mRNA of 1.6 kb hybridizes to the cytochrome c oxidase subunit II gene, while in male sterile plants a transcript of this size is lacking and instead a major transcript of 2.0 kb and two smaller ones occur. The transcript pattern of the F1 ATPase alpha subunit (atpA) gene exhibits slight alterations in sterile plants also. Since these hybrids have the same cytoplasm as normal plants, an incompatibility between the nuclear and the mitochondrial genotype may be responsible for the altered mitochondrial gene expression. No alteration of the transcripts of the mitochondrial genes tested could be detected in dwarf hybrids. The coincidence of male sterility with an altered transcription pattern of mitochondrial genes suggests that the mitochondria are involved in the occurrence of this phenotype.