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81.
Alice L. Hempel Patrick A. Reeves Richard G. Olmstead Robert K. Jansen 《Plant Systematics and Evolution》1995,194(1-2):25-37
Subclass and ordinal relationships ofLoasaceae, a small predominately New World family, are examined usingrbcL sequence data. Sequences were examined for eight of the fifteen genera of theLoasaceae and the morphologically anomalous aquatic genusHydrostachys (Hydrostachyaceae). Parsimony analyses of these sequences, combined with previously publishedrcbL data, indicate thatLoasaceae belong in theCornales, and are the sister group ofHydrangeaceae. This agrees with phylogenies based on chloroplast DNA inverted repeat restriction site, morphological and chemical data. TherbcL trees support the monophyly of theLoasaceae and most generic relationships correspond to current subfamily divisions. TherbcL phylogeny also provides the first suggestion thatHydrostachys is allied with theHydrangeaceae in theCornales. 相似文献
82.
Alice Abd El-Aleem Ingolf Böhm Samia Temtamy Mostafa El-Awady Mohamed Awadalla Jörg Schmidtke Manfred Stuhrmann 《Human genetics》1995,96(5):577-584
Molecular genetic analysis of individuals from 6 Egyptian and 33 German families with fragile X syndrome and 240 further patients with mental retardation was performed applying a completely non-radioactive system. The aim of our study was the development of a non-radioactive detection method and its implementation in molecular diagnosis of the fragile X syndrome. Furthermore, we wanted to assess differences in the mutation sizes between Egyptian and German patients and between Egyptian and German carriers of a premutation. Using non-radioactive polymerase chain reaction (PCR), agarose gel electrophoresis and blotting of the PCR products, followed by hybridisation with a digoxigenin-labelled oligonucleotide probe (CGG)5 and chemiluminescent detection, we identified the fragile X full mutation (amplification of a CGG repeat in the FMR-1 gene ranging from several hundred to several thousand repeat units) in all patients. We observed no differences in the length of the CGG repeat between the Egyptian and German patients and carriers, respectively. However, in one prenatal diagnosis, we detected only one normal sized allele in a female fetus using the PCR-agarose assay, whereas Southern blot analysis with the digoxigenin labelled probe StB 12.3 revealed presence of a full mutation. Our newly established nonradioactive genomic blotting method is based on the conventional radioactive Southern blot analysis. Labelling of the probe StB 12.3 with digoxigenin via PCR allowed the detection of normal, premutated and fully mutated alleles. For exact sizing of small premutated or large normal alleles, we separated digoxigenin labelled PCR products through denaturing poly-acrylamide gelelectrophoresis (PAGE) and transfered them to a nylon membrane using a gel dryer. The blotted PCR-fragments can easily be detected with alkaline phosphate-labelled anti-digoxigenin antibody. The number of trinucleotide repeat units can be determined by scoring the detected bands against a digoxigenated M13 sequencing ladder. Our newly developed digoxigenin/chemiluminescence approach using PCR and Southern blot analysis provides reliable results for routine detection of full fragile X mutations and premutations. 相似文献
83.
Martina M. Uttenreuther-Fischer Chuin-Sheng Huang Ralph A. Reisfeld Alice L. Yu 《Cancer immunology, immunotherapy : CII》1995,41(1):29-36
A phase I trial of a murine anti-ganglioside (GD2) monoclonal antibody (mAb) 14G2a was conducted in 14 neuroblastoma patients and 1 osteosarcoma patient to assess its safety, toxicity and pharmacokinetics in pediatric patients. The pharmacokinetics of mAb 14G2a were biphasic with at
1
2/
of 2.8±2.8 h and at
1
2/
of 18.3±11.8 h. In general,t
1
2/
was dose-dependent with a level of significance ofP=0.036, and it reached a plateau at doses of 250 mg/m2 or more. Overall the peak serum levels were dose-dependent atP<0.001. However, they demonstrated an abrupt increase between doses of 100 mg/m2 and 250 mg/m2. The latter two suggest a saturable mechanism for mAb elimination. In addition, peak serum concentrations were observed earlier at higher mAb doses, which indicates the achievement of a steady state. Thet
1
2/
of mAb 14G2a in children appears to be shorter than in adults. Furthermore, 2 patients demonstrated a considerable decrease int
1
2/
following retreatment with 14G2a. This was paralleled by high human anti-(mouse Ig) antibody levels. This study represents the first comprehensive analysis of murine mAb pharmacokinetics in children and will be useful in the future design of mAb therapy.This work was supported by grants from FDA, FD-R-000377 and NIH U10 CA 28439 and in part by a grant from the general Clinical Research Center program, MOI RR00827, of the National Center for Research Resources, National Institutes of Health. M. M. U.-F. and C.-S. H. were supported in part by a grant from the Children's Cancer Research Foundation, and R. A. R. was supported in part by NIH grant CA 42508 相似文献
84.
Summary Direct delivery of DNA into embryogenic pollen was used to produce transgenic plants in tobacco. A plasmid bearing the ß-glucuronidase (GUS) marker gene in fusion with the 35S-promoter was introduced by microprojectile bombardment into mid-binucleate pollen of Nicotiana tabacum that had been induced to form embryos by a starvation treatment. In cytochemical expression assays, 5 out of 104 pollen grains were GUS+. Visual selection by staining with a non-lethal substrate for GUS was used to manually isolate transformed embryos. From the initial population of embryogenic GUS+ pollen, 1–5% developed into multicellular structures and 0.02% formed regenerable embryos. Two haploid transformants were regenerated. GUS expression was detected in different parts of the plants, and Southern analysis confirmed stable integration of the foreign DNA. Diploidisation was induced by injection of colchicine into the stem near adventitious buds. Offspring from selfings and backcrosses of one transformant were tested for GUS expression and by Southern blots. All F1-plants were transgenic, in accordance with Mendelian inheritance.Abbreviations GUS
ß-glucuronidase
- CaMV
Cauliflower Mosaic Virus
- MCS
multicellular structure
- NPTII
neomycin phosphotransferase
- PEG
polyethylene glycol
- X-gluc
5-bromo-4-chloro-3-indolyl glucuronide
- DAPI
4,6-diamidino-2-phenylindole
- Tris
Tris(hydroxymethyl)aminomethane hydrochloride
- EDTA
ethylenedinitrilo tetraacetic acid, disodium salt dihydrate 相似文献
85.
Adherence through carbohydrate-binding adhesins is an earlystep in colonization of the lung by gram-negative organisms,and because published data indicate that binding involves mannosegroups, we tested the ability of a ß-linked acetylmannan(acemannan) to inhibit adherence of Pseudomonus aeruginosa tocultures of human lung epithelial cells. Adherence of radiolabelledP.aeruginosa to A549 cells (a type II-like pneurnocyte line)increased linearly with the duration of the incubation. Acemannaninhibited adherence of bacteria, and the extent of inhibitionwas related to the concentration of the mannan. Inhibition requiredcontinued contact between acemannan and the target epithelialcells; cells washed free of acemannan no longer discouragedbacterial binding. Comparison of binding between seven strainsof P.aeruginosa indicated that fewer mucoid than non-mucoidbacteria adhered, but binding of either phenotype was inhibitedby acemannan. Mannose methyl -D-mannopyranoside, methyl ß-D-mannopyrannosideand dextran did not affect adherence of any of the non-mucoidstrains. Mannose inhibited adherence by one mucoid strain, butnot the other, indicating differences between strains of thesame phenotype. Since prior treatment of epithelial cells withconcanavalin A did not affect acemannan-induced inhibition ofbacterial adherence, we concluded that the inhibitory effectof acemannan probably does not involve mannose-containing receptors. bacterial-host interactions lung epithelium mucoid strains non-mucoid strains 相似文献
86.
Alice H. Lin Patricia L. Ruppel Robert R. Gorman 《Prostaglandins & other lipid mediators》1984,28(6):837-849
[3H] Leukotriene B4 (LTB4) binds concentration dependency to intact human polymorophonuclear leukocytes (PMN's). The binding is saturable, reaches equilibrium in 10 min at 4°C, and is readily reversible. Mathematical modeling analysis reveals biphasic binding of [3H] LTB4 indicating two discrete populations of binding sites. The high affinity binding sites have a dissociation constant of 0.46 × 10−9M and Bmax of 1.96 × 104 sites per neutrophil; the low affinity binding sites have a dissociation constant of 541 × 10−9M and a Bmax of 45.6 × 104 sites per neutrophil. Competitive binding experiments with structural analogues of LTB4 demonstrate that the interaction between LTB4 and the binding site is stereospecific, and correlates with the relative biological activity of the analogs. At 25°C[3H] LTB4 is rapidly dissociated from the binding site and metabolized to 20-OH and 20-COOH-LTB4. Purification of neutrophils in the presence of 5-lipoxygenase inhibitors significantly increases specific [3H] LTB4 binding, suggesting that LTB4 is biosynthesized during the purification procedure. These data suggest that stereospecific binding and metabolism of LTB4 in neutrophils are tightly coupled processes. 相似文献
87.
The thermal induction of chemiluminescence of luminol-horseradish peroxidase-labeled erythrocytes from pigs, rats, and man was studied. The luminescent responses of rat, porcine, and human erythrocytes to heating were linear in respect to logs of counts per minute versus temperature. Landrace-Duroc crossbred pigs with a history of malignant hyperthermia (porcine stress syndrome) and Poland-China-miniature pigs inbred for malignant hyperthermia (MH) yielded erythrocytes with high-level thermochemiluminescence (TCL). Sprague-Dawley rat erythrocytes were intermediate in their production of TCL. Normal human and MH-resistant miniature swine erythrocytes produced low-level TCL. However, pretreatment of human erythrocytes with 1-chloro-2,4-dinitrobenzene (CDNB) resulted in high-level TCL. Furthermore, halothane enhanced the TCL of CDNB-treated human erythrocytes and Landrace-Duroc porcine erythrocytes that were not treated with CDNB. Red blood cells from pigs susceptible to the porcine stress syndrome demonstrated a TCL response very similar to CDNB-treated erythrocytes. 相似文献
88.
Ade–H and ade–I are two auxotrophic mutants of Chinese hamster ovary (CHO-K1) cells which specifically require adenine as the purine source to grow. The enzymatic defects of these mutants were examined in cell-free extracts. It was found that ade–H did not have any detectable adenylosuccinate synthetase activity and ade–I was defective in the adenylosuccinate lyase enzyme. The relevance of adenine-requiring mutants to the study of the regulation of purine metabolism in mammalian cells is discussed.This work was supported by research grants from the National Institute of Aging (AG00029) and the National Foundation, March of Dimes (1-423), and by a contract from the Center for Toxicological Research, Food and Drug Administration (72-213). David Patterson is a recipient of a Research Career Development Award from the National Institute of Arthritis, Metabolic and Digestive Diseases (AM00044).Contribution (No. 218) from the Eleanor Roosevelt Institute for Cancer Research. 相似文献
89.
Postreplication repair in Neurospora crassa 总被引:1,自引:0,他引:1
Summary Changes in the molecular weight of nascent DNA made after ultraviolet (UV) irradiation have been studied in the excision-defective Neurospora mutant uvs-2 using isotopic pulse labeling, alkaline gradient centrifugation and alkaline filter elution. Both the size of nascent DNA and the rate of incorporation of label into DNA was reduced by UV light in a dose dependent manner. However, this DNA repair mutant did recover the ability to synthesize control-like high molecular weight DNA 3 hours after UV treatment, although the rate of DNA synthesis remained depressed after the temporary block to elongation (or ligation) had been overcome. Photoreactivation partially eliminated the depression of DNA synthesis rate and UV light killing of cells, providing strong evidence that the effects on DNA synthesis and killing were caused by pyrimidine cyclobutane dimers. The caffeine inhibition repair studies performed were difficult to quantitate but did suggest either partial inhibition of a single repair pathway or alternate postreplication DNA repair pathways in Neurospora. No enhancement in killing was detected after UV irradiation when cells were grown on caffeine containing plates. 相似文献
90.
A novel reporter group delivery system for the chemical modification of proteins and the investigation of enzyme mechanisms is proposed. The design of this system is based on structural analogy with pyridoxal phosphate and σ-complex adduct formation. Progress is described toward the synthesis of suitable compounds, via three different approaches involving structural modification of the pyridine nucleus. A number of new compounds have been prepared, and other directions for future investigations are indicated. 相似文献