Anilinonaphthalene sulfonate fluorescence and amino acid transport in yeast

Summary Fluorescence of 1-anilinonaphthalene-8-sulfonate in yeast membranes appears to be caused predominantly by binding to lipids (ANS_proteinANS_lipid120) as indicated by the fluorescence lifetime, degree of polarization, and excitation spectra. It was insensitive to short-circuiting the membrane potential. Fluorescence intensity increased as cells (especially after pretreatment with energy donors such as glucose) were exposed to some amino acids, in particular, aspartic and glutamic acids. The character of fluorescence shifted to that of protein-bound ANS, suggesting an exposure of new protein sites accessible to the probe. This shift could be prevented by inhibitors of energy transduction as well as of transport. TheK _1/2 of the shift was at 2.5mm aspartic acid.     

Some notes on estimation of the basic homoteneity-coefficient of sets of phytosociological relevés

The formula for calculation of the basic homotoneity-coefficient of sets of phytosociological relevés does not give adequate values for sets of 4 or 3 relevés. Therefore an empirical correction procedure is proposed for the calculation of this coefficient for such small sets of relevés. For sets of 2 relevés the calculation of the basic homotoneity-coefficient gives values equal toSørensen’s coefficient of floristic similarity. A simplification of calculation of the basic homotoneity-coefficient for sets of more than 20 relevés is proposed.     

Radiorespirometric study of the utilization of exogenous sucrose,glucose and fructose by germinating apple pollen

Po?adí intensity, s jakou prodýchávají pylové lá?ky testované cukry z 0,3 M roztok?, je sacharosa> glukosa> invertní cukr> fruktosa. Stejné po?adí je zaehováno na cukr-agarových mediích s výjimkou prvých dvou hodin inkubace, během kterých jsou sacharosa, glukosa a fruktosa prodýchávány témě? stejnou rychlostí. Během této doby se v prost?edí fruktosy, stejně jako v kontrole bez cukru, nevytvo?ily pylové lá?ky, zatím za p?itomnosti sacharosy dosahovaly délky a? 450 µ. Jestli?e byla pou?ita pro radioaktivní cukry jako nosi? sacharosa, byla fruktosa-¹⁴C prodýchávána a? 12krát, glukosa-¹⁴C a? 6krât intensivnëji neá sacharosa-¹⁴C. Za pou?ití nosi?e sacharosa+glukosa ?i sacharosa+fruktosa (molárni poměry 1:1), prodýchávaji pylové lácky sacharosu-¹⁴C pomaleji ne? p?íslu?ny monosaeharid a rovně? pomaleji ne? z prost?edí samotnéé sacharosy. Jestli?e byla nosi?em sacharosy-¹⁴C glukosa nebo fruktosa, byla (v některých ?asových úsecíeh pokusu) produkce¹⁴CO₂ pylovými láckami několik desítek procent mohutněj?í ne? za pou?ití nosi?e sacharosového. Z prost?edí invertního cukru je p?ednostně prodýchäväna fruktosa. Je tedy kapacita pylových enzymových systém? za?leňujících sledované cukry do jejich dýchacích cest pro fruktosu>glukosu> sacharosu, co? je opa?né po?adí ne? platí pro intensitu r?stového ú?inku těchto cukr? a ne? jaké bylo zji?těno pro rychlost jejich prodýchávání, jestli?e nebyly navzájem kombinovány. Ve specifickém r?stovém efektu sacharosy nem??e tedy být primárním faktorem ani rychlost její absorpce, ani intensita jejího prodýcháváni. Rychlá utilisace samotné sacharosy je následkem intensivněj?ího r?stu v jejím prost?edí. Získané výsledky dále ukazují, ?e sacharosa je vyu?ívána p?edev?ím cestou její inverse, p?i ?em? je p?ednostně prodýchávána fruktosová slo?ka.     

Partial trisomy 4q syndrome: Case report and review

Summary In the course of chromosome studies of atomic bomb survivors in Hiroshima using the trypsin-G-banding and Q-banding methods, a 40-year-old male was found to have an abnormal banding pattern in the long arm of a chromosome 7, although no such abnormality was detected by ordinary staining method. Since all other chromosomes apparently had normal banding patterns, the abnormality was determined to be a paracentric inversion of a chromosome 7, which is described as 46,XY,inv(7)(q22q31). This is the first demonstration of a possible paracentric inversion in man.     

Constraints on the biological recovery of the Bohemian Forest lakes from acid stress

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Differentially methylated genes and androgen receptor re-expression in small cell prostate carcinomas

Small cell prostate carcinoma (SCPC) morphology is rare at initial diagnosis but often emerges during prostate cancer progression and portends a dismal prognosis. It does not express androgen receptor (AR) or respond to hormonal therapies. Clinically applicable markers for its early detection and treatment with effective chemotherapy are needed. Our studies in patient tumor–derived xenografts (PDX) revealed that AR–negative SCPC (AR^?SCPC) expresses neural development genes instead of the prostate luminal epithelial genes characteristic of AR–positive castration-resistant adenocarcinomas (AR⁺ADENO). We hypothesized that the differences in cellular lineage programs are reflected in distinct epigenetic profiles. To address this hypothesis, we compared the DNA methylation profiles of AR^? and AR⁺ PDX using methylated CpG island amplification and microarray (MCAM) analysis and identified a set of differentially methylated promoters, validated in PDX and corresponding donor patient samples. We used the Illumina 450K platform to examine additional regions of the genome and the correlation between the DNA methylation profiles of the PDX and their corresponding patient tumors. Struck by the low frequency of AR promoter methylation in the AR^?SCPC, we investigated this region's specific histone modification patterns by chromatin immunoprecipitation. We found that the AR promoter was enriched in silencing histone modifications (H3K27me3 and H3K9me2) and that EZH2 inhibition with 3-deazaneplanocin A (DZNep) resulted in AR expression and growth inhibition in AR^?SCPC cell lines. We conclude that the epigenome of AR^? is distinct from that of AR⁺ castration-resistant prostate carcinomas, and that the AR^? phenotype can be reversed with epigenetic drugs.     

Application of Concanavalin A during immune responsiveness skin‐swelling tests facilitates measurement interpretation in mammalian ecology

The skin‐swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue swelling response at specific times following subcutaneous application of an experimental pro‐inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the skin‐swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of skin‐swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro‐inflammatory stimulant in mice. We measured magnitude of tissue swelling and compared it with intensity of blood cell infiltration into tissue over a 72‐hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger swelling with a distinct leukocyte activity pattern and higher pro‐inflammatory cytokine (interleukin 6 [IL‐6] and interferon gamma[IFN‐γ]) expression than PHA during peak response (24‐h post‐treatment). Furthermore, unlike PHA, magnitude of swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for skin‐swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in mammals as it exhibits better performance and its application facilitates immunological interpretation of skin‐swelling test results.     

Evolutionary conservation of kinetochore protein sequences in plants

The evolutionary conservation of structural/functional kinetochore proteins has been studied on isolated nuclei and pro-/metaphase chromosomes of mono- and dicot plants. The cross-reactivities of antibodies against human CENPC, CENPE and CENPF, and against maize CENPCa with the centromeric regions of mitotic chromosomes of Vicia faba and/or Hordeum vulgare are shown. Putative homologs of the kinetochore protein SKP1 (suppressor of kinetochore protein 1p of yeast) were found in both species and of CBF5p (centromere binding factor 5 of yeast) in barley. Antibodies against synthetic peptides derived from partial sequences encoding these proteins were produced and recognized the centromeric regions on mitotic chromosomes as detected by indirect immunofluorescence.