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1.
Development of a single probe for documentation of chimerism following bone marrow transplantation. 总被引:2,自引:0,他引:2 下载免费PDF全文
Although numerous genetic markers are available for studying chimerism after bone marrow transplantation (BMT), there remains a need for a practical and highly informative method that is applicable in the early posttransplantation period. Using DNA restriction-fragment-length polymorphisms (RFLPs), we have evaluated the feasibility of developing a single synthetic oligonucleotide probe to study post-BMT chimerism. We have thus tested three candidate probes, termed O-3315-32, O-3315-80, and O-AY-29, that are homologous to tandemly repetitive sequences. Our results demonstrated donor-specific and recipient-specific fragments in 11 of 11 HLA-matched sibling pairs tested using probes O-3315-32 and O-3315-80. When probe O-AY-29 was used, 14 of 17 sibling pairs showed both donor and recipient markers, one had only a recipient marker, and two were identical. We showed that each of the three synthetic probes was effective in documenting donor marrow engraftment, mixed hematopoietic chimerism, the patient's pre-BMT phenotype (by using cultured skin fibroblasts obtained after BMT), and the origin of the malignant hematopoietic cells (i.e., of donor or recipient origin) in patients who developed recurrent hematologic malignancy following BMT. Compared with the use of cloned genomic probes, there are several important advantages to the use of synthetic oligonucleotide probes in studying post-BMT chimerism. Synthetic probes have absolute hybridization specificity and can be designed to suit the purposes of an individual study, since they have adjustable specificity that can be altered by changes in the length of the probe and by changes in the hybridization temperature. A single synthetic probe analogous to several highly polymorphic loci can have a polymorphism information content sufficiently high so that all but a small percentage of BMT patients could be followed easily; for example, if a probe were complementary to three highly polymorphic unlinked loci, it would discriminate approximately 98% of sibling donor/recipient pairs. This would be accomplished using only one restriction-endonuclease digestion and only one gel electrophoresis. Since other genetic markers, e.g., red blood cell antigens, immunoglobulin allotypes, and chromosome analysis, are not uniformly informative and, in some cases, cannot be used in the early posttransplantation period, the use of synthetic oligonucleotide probes for analysis of DNA RFLP is emerging as the method of choice for studies of post-BMT chimerism. This method will allow for the development of new knowledge that has not been possible with previous methods. 相似文献
2.
Cytologic examination of the pleural effusion from a patient with acute leukemia, leukocytosis and bleeding revealed the presence of many leukemic cells, "lymphocytes" and erythrocytes. The significance of these cellular changes was investigated by simultaneous study of blood and effusion leukocytes by morphologic, cytochemical and immunochemical methods. Both the leukemic blasts and the "lymphocytes" in the effusion and the blood were found to be neoplastic and contained antigens characteristic of both myeloid cells (OKM-1) and lymphoblasts (C-ALLA, common acute lymphoblastic leukemia antigen). These results, when analyzed in the context of the clinical findings, were indicative of acute leukemia with pleural involvement. Such a clinically oriented approach may further enhance the potential of cytodiagnosis in patients with serous effusions. 相似文献
3.
4.
Singapore is located near the equator, off the southern tip of the Malay Peninsula. The whole country consists mostly of lowland.
It has many interesting types of natural habitats such as primary rain forest, freshwater swamp forest, mangroves, secondary
forests, shrub, grasslands, and urban parks and fields. The climate is equatorial with relatively uniform temperature and
high humidity. Unfortunately, many of the natural habitats and the native orchids which thrive there have disappeared due
to habitat destruction. Some 226 species of native orchids have been recorded in Singapore. However, of these 178 are considered
to be extinct, and only five are common. The orchid conservation programme aims to monitor existing species, explore ways
to conserve their germplasm, and increase their numbers in natural, semi-natural, and urban environments through ex-situ seedling
culture and subsequent re-introduction into appropriate habitats, including roadside trees, parks and natural areas. In the
first phase of the programme, we have successfully propagated and carried out experiments of re-introduction on five species
of native orchids, namely, Grammatophyllum speciosum, Bulbophyllum vaginatum, Bulbophyllum membranaceum, Cymbidium finlaysonianum and Cymbidium bicolor. Survival percentages 8-yr after the reintroduction events ranged from 10 to 95 for G. speciosum, the target species of the earliest re-introduction experiments. Size of the seedlings at reintroduction, host trees, and
relative humidity seemed to play significant roles in the success rate of the reintroductions. 相似文献
5.
Su‐Ching Chang Dale Tshudy Ulf Sorhannus Shane T. Ahyong Tin‐Yam Chan 《Zoologica scripta》2017,46(3):372-387
Deep‐sea lobsters previously assigned to the family Thaumastochelidae Bate, 1888, the thaumastocheliforms, have very distinctive, greatly unequal first chelipeds, with the right side extremely elongate and pectinate, and in having short, quadrate pleonal pleura. Despite interesting morphology and a long taxonomic history, the phylogeny of the group has received little detailed analysis. Here, we conduct a species‐level phylogenetic analysis of the thaumastocheliforms based on morphological and molecular data (three mitochondrial genes: COI, 16S rDNA and 12S rDNA; two nuclear protein‐coding genes: H3 and NaK) to robustly reconstruct their evolutionary history and estimate divergence times. Separate and combined analyses of all data sources support thaumastocheliform monophyly, but as a clade deeply nested within the Nephropidae supporting recent synonymy of Thaumastochelidae with Nephropidae. Combined and molecular‐only analyses support generic monophyly of all three thaumastocheliform genera and Dinochelus as sister to Thaumastochelopsis, fully corroborating the current, morphology‐based taxonomy. In contrast, Thaumastocheles is recovered as paraphyletic in morphology‐only analyses owing to minimal character support. The Cretaceous–Paleogene Oncopareia was recovered as a stem‐lineage thaumastocheliform. The fossil record indicates that the thaumastocheliforms once lived in shallow, continental shelf depths, but moved into deeper water in the Cenozoic where they occur today. The thaumastocheliforms originated in northern Europe during the Mid‐Late Cretaceous and later dispersed westwards to the south‐eastern Pacific through the western Atlantic and eastwards to the western Pacific through the Indian Ocean. Thaumastochelopsis can be considered the most derived thaumastocheliform genus based on the degree of structural reduction relative to other thaumastocheliforms, its remote geographical occurrence (Australia) from the hypothesised place of origin (northern Europe) and its more recent estimated divergence than other genera (28 Mya for the MRCA of extant species of the genus). 相似文献
6.
Xian-He Bu He LiuMiao Du Keith Man-Chung WongVivian Wing-Wah Yam 《Inorganica chimica acta》2002,333(1):32-40
The complexes of Cu(I), Cu(II), Ni(II), Zn(II) and Co(II) with a new polypyridyl ligand, 2,3-bis(2-pyridyl)-5,8-dimethoxyquinoxaline (L), have been synthesized and characterized. The crystal structures of these complexes have been elucidated by X-ray diffraction analyses and three types of coordination modes for L were found to exist in them. In the dinuclear complex [Cu(I)L(CH3CN)]2·(ClO4)2 (1), L acts as a tridentate ligand with two Cu(I) centers bridged by two L ligands to form a box-like dimeric structure, in which each Cu(I) ion is penta-coordinated with three nitrogen atoms and a methoxyl oxygen atom of two L ligands, and an acetonitrile. In [Cu(II)L(NO3)2]·CH3CN 2, the Cu(II) center is coordinated to the two nitrogen atoms of the two pyridine rings of L which acts as a bidentate ligand. The structures of [Ni(II)L(NO3)(H2O)2]·2CH3CN·NO3 (3), [Zn(II)L(NO3)2 (H2O)]·2CH3CN (4) and [Co(II)LCl2(H2O)] (5) are similar to each other in which L acts as a tridentate ligand by using its half side, and the metal centers are coordinated to a methoxyl oxygen atom and two bipyridine nitrogen atoms of L in the same side. The formation of infinite quasi-one-dimensional chains (1, 4 and 5) or a quasi-two-dimensional sheet (2) assisted by the intra- or intermolecular face-to-face aryl stacking interactions and hydrogen bonds may have stabilized the crystals of these complexes. Luminescence studies showed that 1 exhibits broad, structureless emissions at 420 nm in the solid state and at 450 nm in frozen alcohol frozen glasses at 77 K. Cyclic voltammetric studies of 1 show the presence of an irreversible metal-centered reduction wave at approximately −0.973 V versus Fc+/0 and a quasi-reversible ligand-centered reduction couple at approximately −1.996 V versus Fc+/0. The solution behaviors of these complexes have been further studied by UV-Vis and ESR techniques. 相似文献
7.
Degradation of cyclin A does not require its phosphorylation by CDC2 and cyclin-dependent kinase 2 总被引:8,自引:0,他引:8
Many cyclins are degraded by the ubiquitination/proteasome pathways involving the anaphase-promoting complex and SCF complexes. These degradations are frequently dependent on phosphorylation by cyclin-dependent kinases (CDKs), providing a self-limiting mechanism for CDK activity. Here we present evidence from in vitro and in vivo assay systems that the degradation of human cyclin A can be inhibited by kinase-inactive mutants of CDK2 and CDC2. One obvious interpretation of these results is that like other cyclins, CDK-dependent phosphorylation of the cyclin A may be involved in cyclin A degradation. Our data indicated that CDK2 can phosphorylate cyclin A on Ser-154. Site-directed mutagenesis of Ser-154 abolished the phosphorylation by recombinant CDK2 in vitro and the majority of cyclin A phosphorylation in the cell. Activation of CDK2 and binding to SKP2 or p27(KIP1) were not affected by the phosphorylation of Ser-154. Surprising, in marked contrast to cyclin E, where phosphorylation of Thr-380 by CDK2 is required for proteolysis, degradation of cyclin A was not affected by Ser-154 phosphorylation. It is likely that the stabilization of cyclin A by the kinase-inactive CDKs was mainly due to a cell cycle effect. These data suggest an important difference between the regulation of cyclin A and cyclin E. 相似文献
8.
Summary Axillary bud expiants from South Pacific (Solomon Islands) taro, Colocasia esculenta var. esculenta cv. Akalomamale (Araceae) cultured on a modified Murashige-Skoog medium containing 1 mg NAA 1–1 and TE formed callus and produced multiple plantlets. Explants died if NAA was present at levels lower than 0.1 mg 1–1. BA was not required and may have been inhibitory. Plantlets developed faster and became larger following transfer to a hormone-free medium two weeks after the start of culture. Fully grown plants were established in a potting mix and are growing well in a greenhouse.Abbreviations BA
benzyladenine
- BM
basal medium
- Ca
Colocasia esculenta var. antiquorum
- Ce
Colocasia esculenta var. esculenta
- Ck
cytokinin(s)
- CW
coconut water
- HSMSM
half strength Murashige Skoog macroelements
- HSMS
half strength Murashige and Skoog medium
- IM
initial medium(ia)
- MS
Murashige and Skoog medium
- NAA
naphthaleneacetic acid
- SM
second medium
- TE
taro corm extract
- UCI
University of California, Irvine 相似文献
9.
Annerieke C van Groenestijn Ingrid GL van de Port Carin D Schröder Marcel WM Post Hepke F Grupstra Esther T Kruitwagen Harmen van der Linde Reinout O van Vliet Margreet GH van de Weerd Leonard H van den Berg Eline Lindeman 《BMC neurology》2011,11(1):1-11
Background
Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.Methods
We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.Results
Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.Conclusions
The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain. 相似文献10.