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941.
N. Ito Shunsuke Imai Satoshi Haga Chieko Nagaike Yoshihumi Morimura Katsuhiko Hatake 《Histochemistry and cell biology》1996,106(3):331-339
Several studies have shown the deletion of blood group A or B antigens and the accumulation of H antigens in human breast
carcinomas. Other studies have independently demonstrated that the binding sites of lectins such asHelix pomatia agglutinin (HPA) andGriffonia simplicifolia agglutinin I-B4 (GSAI-B4) are highly expressed in these cells. In order to clarify the molecular mechanisms of malignant transformation and metastasis
of carcinoma cells, it is important to understand the relationship between such phenotypically distinct events. For this purpose,
we examined whether the binding sites of these lectins andUlex europaeus agglutinin I (UEA-I) are expressed concomitantly in the same carcinoma cells and analyzed their backbone structures. The
expression of the binding sites of these lectins was observed independently of the blood group (ABO) of the patients and was
not affected by the histological type of the carcinomas. Observation of serial sections stained with these lectins revealed
that the distribution of HPA binding sites was almost identical to that of GSAI-B4 in most cases. Furthermore, in some cases, UEA-I binding patterns were similar to those of HPA and GSAI-B4 but in other cases, mosaic staining patterns with these lectins were also observed, i.e., some cell clusters were stained
with both HPA and GSAI-B4 but not with UEA-I and adjacent cell clusters were stained only with UEA-I. Digestion with endo-β-galactosidase orN-glycosidase F markedly reduced the staining intensity of these lectins. Together with the reduction of staining by these
lectins, reactivity withGriffonia simplicifolia agglutinin II appeared in carcinoma cells following endo-β-galactosidase digestion. Among the lectins specific to poly-N-acetyllactosamine,Lycopersicon esculentum agglutinin (LEA) most vividly and consistently stained the cancer cells. Next to LEA, pokeweed mitogen agglutinin was also
effective in staining these cells. Carcinoma cells reactive with these lectins corresponded well to those stained with both
HPA and GSAI-B4, and in some cases, with UEA-I. These results demonstrate that the binding sites of UEA-I, HPA, and GSAI-B4 are expressed concomitantly in the same carcinoma cells and all carry linear and branched poly-N-acetyllactosamine onN-glycans, suggesting that the synthesis of this complex carbohydrate is one of the most important and basic processes leading
to the malignant transformation of cells, invasion, and metastasis of carcinoma cells. 相似文献
942.
Measurement of pulmonary blood flow by fractal analysis of flow heterogeneity in isolated canine lungs 总被引:1,自引:0,他引:1
Barman Scott A.; McCloud Laryssa L.; Catravas John D.; Ehrhart Ina C. 《Journal of applied physiology》1996,81(5):2039-2045
Barman, Scott A., Laryssa L. McCloud, John D. Catravas, andIna C. Ehrhart. Measurement of pulmonary blood flow by fractalanalysis of flow heterogeneity in isolated canine lungs. J. Appl. Physiol. 81(5):2039-2045, 1996.Regional heterogeneity of lung blood flow can bemeasured by analyzing the relative dispersion (RD) of mass(weight)-flow data. Numerous studies have shown that pulmonary bloodflow is fractal in nature, a phenomenon that can be characterized bythe fractal dimension and the RD for the smallest realizable volumeelement (piece size). Although information exists for theapplicability of fractal analysis to pulmonary blood flow in wholeanimal models, little is known in isolated organs. Therefore, thepresent study was done to determine the effect of blood flow rate onthe distribution of pulmonary blood flow in the isolated blood-perfusedcanine lung lobe by using fractal analysis. Four different radiolabeledmicrospheres (141Ce,95Nb,85Sr, and51Cr), each 15 µm in diameter,were injected into the pulmonary lobar artery of isolated canine lunglobes (n = 5) perfused at fourdifferent flow rates ( flow1 = 0.42 ± 0.02 l/min;flow2 = 1.12 ± 0.07 l/min;flow 3 = 2.25 ± 0.17 l/min; flow 4 = 2.59 ± 0.17 l/min), and the pulmonary blood flow distribution was measured. Theresults of the present study indicate that under isogravimetric bloodflow conditions, all regions of horizontally perfused isolated lunglobes received blood flow that was preferentially distributed to themost distal caudal regions of the lobe. Regional pulmonary blood flowin the isolated perfused canine lobe was heterogeneous and fractal innature, as measured by the RD. As flow rates increased, fractal dimension values (averaging 1.22 ± 0.08) remained constant, whereas RD decreased, reflecting more homogeneous blood flowdistribution. At any given blood flow rate, high-flow areas of the lobereceived a proportionally larger amount of regional flow, suggestingthat the degree of pulmonary vascular recruitment may also be spatially related. 相似文献
943.
Mamoru Sugita Chieko Sugita Masahiro Sugiura 《Molecular & general genetics : MGG》1995,246(2):142-147
We isolated a 38 kDa ssDNA-binding protein from the unicellular cyanobacterium Synechococcus sp. strain PCC 6301 and determined its N-terminal amino acid sequence. A genomic clone encoding the 38 kDa protein was isolated by using a degenerate oligonucleotide probe based on the amino acid sequence. The nucleotide sequence and predicted amino acid sequence revealed that the 38 kDa protein is 306 amino acids long and homologous to the nuclear-encoded 370 amino acid chloroplast ribosomal protein CS1 of spinach (48% identity), therefore identifying it as ribosomal protein (r-protein) S1. Cyanobacterial and chloroplast S1 proteins differ in size from Escherichia coli r-protein S1 (557 amino acids). This provides an additional evidence that cyanobacteria are closely related to chloroplasts. The Synechococcus gene rps1 encoding S1 is located 1.1 kb downstream from psbB, which encodes the photosystem 11 P680 chlorophyll a apoprotein. An open reading frame encoding a potential protein of 168 amino acids is present between psbB and rps1 and its deduced amino acid sequence is similar to that of E. coli hypothetical 17.2 kDa protein. Northern blot analysis showed that rps1 is transcribed as a monocistronic mRNA. 相似文献
944.
DNA replication of histone gene repeats in Drosophila melanogaster tissue culture cells: multiple initiation sites and replication pause sites. 总被引:13,自引:7,他引:6
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We showed previously that DNA replication initiates at multiple sites in the 5-kb histone gene repeating unit in early embryos of Drosophila melanogaster. The present report shows evidence that replication in the same chromosomal region initiates at multiple sites in tissue culture cells as well. First, we analyzed replication intermediates by the two-dimensional gel electrophoretic replicon mapping method and detected bubble-form replication intermediates for all fragments restricted at different sites in the repeating unit. Second, we analyzed bromodeoxyuridine-labeled nascent strands amplified by the polymerase chain reaction method and detected little differences in the size distribution of nascent strands specific to six short segments located at different sites in the repeating unit. These results strongly suggest that DNA replication initiates at multiple sites located within the repeating unit. We also found several replication pause sites located at 5' upstream regions of some histone genes. 相似文献
945.
Inhibition of initiation of mini-F plasmid replication in temperature-sensitive mafA mutants of Escherichia coli K-12 总被引:1,自引:0,他引:1
When temperature-sensitive mafA mutants of Escherichia coli K-12 carrying mini-F plasmid (pSC138) are transferred from 30 to 42 °C, plasmid DNA replication as determined by incorporation of [3H]thymidine into covalently closed circular (CCC) mini-F DNA or by DNA-DNA hybridization is inhibited markedly within 10 min. The results of extensive pulse-chase experiments suggest that the initiation rather than the chain elongation step of plasmid replication is affected under these conditions. The replication inhibition in the mutant is accompanied by appearance of a class of plasmid DNA with a buoyant density higher than that of CCC DNA observed in the wild type, and is followed by gradual inhibition of host cell growth. The inhibition of plasmid replication is reversible at least for 60 min under the conditions used, and the recovery at low temperature (30 °C) depends on the synthesis of untranslated RNA. These results taken together with other evidence suggest that the mafA mutations primarily affect the initial step(s) of F DNA replication, presumably at or before the synthesis of untranslated RNA. 相似文献
946.
947.
Contusion of the cervical spinal cord following dental treatment of a patient at risk to stroke: A case report
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Anna Greta Barbe Michael Johannes Noack Michael Thomas Barbe Ina Nitschke 《Gerodontology》2018,35(1):63-65
Objectives
It is essential that especially elderly patients are correctly positioned in dental chairs, based on medical history and careful observation.Method
We report a case where reclination of the patient's head resulted in weakness of the limbs.Results
Subsequent investigation determined traumatic contusion of the cervical spinal cord.Conclusions
This case highlights the need for accurate anamnesis, close observation and interdisciplinary communication to determine correct positioning. Exceptional circumstances necessitate speedy response to minimise adverse events in elderly patients. 相似文献948.
949.
Ina Mueller Karoline Ehlert Stefanie Endres Lena Pill Nikolai Siebert Silke Kietz 《MABS-AUSTIN》2018,10(1):55-61
Immunotherapy with short term infusion (STI) of monoclonal anti-GD2 antibody (mAb) ch14.18 (4 × 25 mg/m2/d; 8–20 h) in combination with cytokines and 13-cis retinoic acid (RA) prolonged survival in high-risk neuroblastoma (NB) patients. Here, we investigated long-term infusion (LTI) of ch14.18 produced in Chinese hamster ovary cells (ch14.18/CHO; 10 × 10 mg/m2; 24 h) in combination with subcutaneous (s.c.) interleukin-2 (IL-2) in a single center program and report clinical response, toxicity and survival. Fifty-three high-risk NB patients received up to 6 cycles of 100 mg/m2 ch14.18/CHO (d8–17) as LTI combined with 6 × 106 IU/m2 s.c. IL-2 (d1–5; 8–12) and 160 mg/m2 oral RA (d19–32). Pain toxicity was documented with validated pain scores and intravenous (i.v.) morphine usage. Response was assessed in 37/53 evaluable patients following International Neuroblastoma Risk Group criteria. Progression-free (PFS) and overall survival (OS) was analyzed by the Kaplan-Meier method and compared to a matched historical control group from the database of AIEOP, the “Italian Pediatric Ematology and Oncology Association”. LTI of ch14.18/CHO showed acceptable toxicity profile indicated by low pain scores, reduced i.v. morphine usage and low frequency of Grade ≥3 adverse events that allowed outpatient treatment. We observed a best response rate of 40.5% (15/37; 5 CR, 10 PR), 4-year (4 y) PFS of 33.1% (observation 0.1- 4.9 y, mean: 2.2 y) and a 4 y OS of 47.7% (observation 0.27 – 5.20 y, mean: 3.6 y). Survival of the entire cohort (53/53) and the relapsed patients (29/53) was significantly improved compared to historical controls. LTI of ch14.18/CHO thus shows an acceptable toxicity profile, objective clinical responses and a strong signal of clinical efficacy in NB patients. 相似文献
950.
Broad‐scale patterns in smoke‐responsive germination from the south‐eastern Australian flora
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