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81.
A colored banding pattern for human chromosomes is described that distinguishes each chromosome in a single fluorescence
in situ hybridization with a set of subregional DNA probes. Alu/polymerase chain reaction products of various human/rodent
somatic cell hybrids (fragment hybrids) were pooled into two probe sets that were labeled differentially and detected by red
and green fluorescence. Chromosome regions hybridized by DNA present in both pools appeared yellow. The result was a multi-color
set of 110 distinct signals per haploid chromosome set for the human karyotype. Each individual chromosome showed a unique
sequence of signals, a result termed the “chromosome bar code”. The reproducibility of the hybridization pattern in various
labeling and hybridization experiments was analyzed by computer densitometry. We have applied the chromosome bar code both
in diagnostic cytogenetics and in genome studies. The approach allows the rapid identification of chromosomes and chromosome
rearrangements. Although not yet showing the resolution of classical banding patterns, the present experiments demonstrate
various applications in which the present multi-color bar code can significantly add to the spectrum of cytogenetic techniques.
Received: 18 December 1996 / Accepted: 10 February 1997 相似文献
82.
Early detection of bacterial diseases in apple plants by analysis of volatile organic compounds profiles and use of electronic nose 总被引:1,自引:0,他引:1 下载免费PDF全文
A. Cellini E. Biondi S. Blasioli L. Rocchi B. Farneti I. Braschi S. Savioli M.T. Rodriguez‐Estrada F. Biasioli F. Spinelli 《The Annals of applied biology》2016,168(3):409-420
DNA‐based protocols are the standard methods for the diagnosis of infected plant material. Nevertheless, these methods are time‐consuming and require trained personnel, with an efficacy depending on the sampling procedure. In comparison, recognition methods based on volatile compounds emissions are less precise, but allow a non‐destructive mass screening of bulk samples, and may be implemented to steer molecular diagnosis. In this study, the analysis of volatile compounds is used for the discrimination of fire blight (Erwinia amylovora) and blossom blight (Pseudomonas syringae pv. syringae) on apple propagation material. Possible marker compounds were identified by gas chromatography–mass spectroscopy (GC‐MS) and proton transfer reaction‐time of flight‐mass spectroscopy (PTR‐ToF‐MS). In addition, two commercial electronic noses were used for diagnosis. After a preliminary validation in vitro, a diagnostic protocol was successfully developed to scale up to real nursery conditions on cold stored, asymptomatic dormant plants. 相似文献
83.
Synthesis of O-glycosylated tuftsins by utilizing threonine derivatives containing an unprotected monosaccharide moiety 总被引:2,自引:0,他引:2
F Filira L Biondi F Cavaggion B Scolaro R Rocchi 《International journal of peptide and protein research》1990,36(1):86-96
Synthesis is described of four tuftsin derivatives containing a D-glucopyranosyl or a D-galactopyranosyl unit covalently linked to the hydroxy side chain function of the threonine residue through either an alpha or beta O-glycosidic linkage. Fmoc-threonine derivatives containing the suitable unprotected sugar were used for incorporating the O-glycosylated amino acid residue. Z-Thr[alpha-Glc(OBzl)4]-OBzl and Z-Thr[alpha-Gal(OBzl)4]-OBzl were prepared from the tetra-O-benzylated sugar and Z-Thr-OBzl by the trichloroacetimidate method in the presence of trimethylsilyl trifluoromethane sulfonate. The alpha glycosylated threonine derivatives were converted into Fmoc-Thr(alpha-Glc)-OH and Fmoc-Thr(alpha-Gal)-OH by catalytic hydrogenation followed by acylation with Fmoc-OSu. beta-Glucosylation and beta-galactosylation of threonine were carried out by reacting the proper per-O-acetylated sugar with Z-Thr-OBzl and boron trifluoride ethyl etherate in dichloromethane. Catalytic hydrogenation of the beta-O-glycosylated threonine derivatives followed by acylation with Fmoc-OSu and deacetylation with methanolic hydrazine yielded Fmoc-Thr(beta-Glc)-OH and Fmoc-Thr(beta-Gal)-OH, respectively. The O-glycosylated threonine derivatives were then reacted with H-Lys(Z)-Pro-Arg(NO2)-OBzl in the presence of DCC and HOBt and the resulting glycosylated tuftsin derivatives were fully deblocked by catalytic hydrogenation, purified by HPLC, and characterized by optical rotation, amino acid analysis, and 1H NMR. The beta-galactosylated tuftsin was also prepared by the continuous flow solid phase procedure. 相似文献
84.
The rice is important in plant science for its ability to germinate and grow with restricted or without oxygen availability.
In this work we have investigated the variation of growth substances when anoxia was imposed to rice seedlings previously
grown in air. An increase, in all the organs of a seedling and in particular in the fraction released in the medium, was observed
for ABA (abscisic acid), PA (phaseic acid) and DPA (dihydrophaseic acid) quantities.Vice versa a reduction of total IAA (indol-3-ylacetic acid) was observed in seedlings. This was accompanied by its accumulation in roots.
IAA was poorly released in aerobic conditions and anoxia has not changed this pattern. 相似文献
85.
Bruno Filippi Laura Biondi Fernando Filira Raniero Rocchi Cecilia Bellini Giampietro Sarto 《Biopolymers》1983,22(1):575-578
The synthesis in solution of some modified (D)Ala2,Leu5-enkephalins has been carried out. The lipophilic properties of the parent compound have been modified by amidation of the carboxyl function with alkylamines of increasing hydrophilicity to increase permeability of the blood-brain barrier. Attempts to reduce enzymatic degradation have been carried out either by reductive glucosamination or by amidation of the carboxyl function with 2-amino-2-deoxy-β-D-glucopyranose. Esterification of the carboxyl function of (D)Ala2,Leu5-enkephalin with polyethylenglycole 1000 has also been carried out. The effects induced by these modifications have been evaluated by in vitro and in vivo tests. 相似文献
86.
87.
Identification of novel RFLPs in the vicinity of CpG islands in Xq28: application to the analysis of the pattern of X chromosome inactivation. 下载免费PDF全文
E Maestrini S Rivella C Tribioli M Rocchi G Camerino S Santachiara-Benerecetti O Parolini L D Notarangelo D Toniolo 《American journal of human genetics》1992,50(1):156-163
Probes for CpG islands were cloned from the distal long arm of the human X chromosome; three of them were found to be polymorphic. A HindIII RFLP was identified by the probe 2-25 (DXS606), and it was mapped to the Xq27-Xq28 boundary. Probes 2-19 (DXS605) and 2-55 (DXS707), which identify EcoRI and MspI polymorphisms, respectively, have been mapped to the distal part of Xq28, in the G6PD-RCP/GCP gene region. Probe 2-19 has been further localized about 16 kb from the 3' end of the G6PD gene. The new RFLPs may be useful for the precise mapping of the many disease genes localized in this part of the human X chromosome. Probe 2-19 is highly informative, and it has been studied in greater detail. Using the methylation-sensitive rare-cutter enzyme EagI in conjunction with the polymorphic EcoRI site, we were able to demonstrate that the RFLP may be used both to study randomness of X chromosome inactivation and for carrier detection in X-linked syndromes where nonrandom X inactivation occurs. It is conceivable that the combined use of 2-19 and of the probes described so far (pSPT-PGK and M27 beta) will make analysis of X inactivation feasible in virtually every female. 相似文献
88.
Decrease in plasma tryptophan after a tryptophan-free amino acid solution. A comparison between cirrhotic and control subjects 总被引:4,自引:0,他引:4
E A Moja E Rocchi F Benedetti F Paolillo G Casalgrandi M Ponz de Leon 《Life sciences》1991,48(5):409-418
In healthy subjects the administration of an amino acid mixture devoid of tryptophan causes a marked decrease of plasma tryptophan. This is because amino acid mixtures induce protein synthesis and tryptophan in blood is incorporated into newly synthesized proteins. We hypothesized that a tryptophan-free mixture could differently affect plasma tryptophan levels in subjects with an impaired protein synthesis such as chronic liver patients. We studied tryptophan levels after a tryptophan-free amino acid solution in controls and cirrhotics fasting 12 hours. Plasma total tryptophan fell to 91% of the initial level 60 minutes after the administration of the diet, to 71% after 120, and to 50% after 210' in controls. In cirrhotics the solution caused a decrease of plasma tryptophan that began significantly later than in controls, the delay being proportional to the severity of the disease. Cirrhotics were subdivided into two groups in accordance to the Pugh modification of the Child-Turcotte criteria. Total plasma tryptophan was 100% of base line levels after 60', 88% after 120', and 65% after 210' in less severe clinical condition; total plasma tryptophan was 102% of base line levels after 60', 98% after 120', and 75% after 210' in more severe clinical condition. 相似文献
89.
Mariano Rocchi Nicoletta Archidiacono Giovanni Romeo Marco Saginati Luciano Zardi 《Human genetics》1991,86(6):621-623
Summary Tenascin (TN) is a hexameric extracellular matrix glycoprotein that is highly expressed in solid tumors but has a restricted distribution in normal adult tissues. Each TN subunit is composed of segments with high homology to the sequences of epidermal growth factor, fibronectin and fibrinogen. Furthermore, it has been suggested that TN could modulate epithelial-mesenchymal and neuronal-glial interactions. Here, using a cDNA probe to human TN, we have carried out Southern blot analysis of the genomic DNAs from a panel of human-hamster somatic cell hybrids carrying different complements of human chromosomes. The results demonstrate that the human TN gene is located on chromosome 9. Furthermore, in situ hybridization studies demonstrate that human TN is located at 9q32–q34. 相似文献
90.