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21.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
22.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献23.
Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies 总被引:1,自引:0,他引:1
Terresa Nusair Reuben Baumal Robert Rosenstein Trond Jørgensen Alexander Marks 《Molecular immunology》1983,20(5):537-547
The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H315 L315 and F315V but not with free H315, L315, V315H or V3152. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted. 相似文献
24.
Robert B. Page Jeffrey M. Rosenstein Barbara J. Dovey Alphonse E. Leure-Dupree 《Anatomical record (Hoboken, N.J. : 2007)》1979,194(1):83-103
A morphologic investigation of ependyma over gray matter (caudate nucleus) and over periventricular white matter (tapetum) of the rabbit lateral ventricle was performed four months after the induction of experimental hydrocephalus. Ependymal cells over the caudate nucleus are not modified by hydrocephalus. They remain cuboidal and heavily ciliated. Numerous microvilli cover the cell surface. The extracellular space of the neuropil is not expanded. Ependymal cells over the periventricular white matter are markedly modified. The characteristic response of these ependymal cells is to enlarge and to form lacunae in their apical cytoplasm. Their apical, horizontal cytoplasmic processes elongate as adjacent ependymal cells separate. The ex-tracellular space of the neuropil is expanded. It is proposed that the changes seen in ependymal cells over periventricular white matter are a response to enlargement of the ventricular surface permitted by the orientation of neuronal and glial fibers parallel to the ventricular surface. With expansion of the ventricular surface, overlapping apical processes become elongated and modified, containing a terminal web. With further enlargement, sliding of an overlapping apical process of one cell uncovers the apical process of its neighboring cell. By this mechanism, the ventricular surface area of any ependymal cell whose surface has been partially covered by its neighbor is increased. With further progression, this compensation fails and the neuropil is exposed to the ventricular cavity. Over caudate nucleus, expansion of ventricular surface is hindered by the disposition of fascie adherentes along intercellular clefts oriented perpendicular to the ventricular surface. Lateral sliding of horizontal apical processes does not occur as such processes are not found in ependyma over the caudate nucleus. The differential response of the ventricular surface in these two areas characteristically seen in hydrocephalus is; determined by regional differences in the morphology of their ependymal cells and underlying neuropil. 相似文献
25.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
26.
Providing cost-effective high quality healthcare services ranks as the number one concern for anyone involved with the healthcare delivery system. While quality of care should always be the number one priority, controlling healthcare costs receives most of the attention. With limited healthcare dollars and providers assuming more of the financial risk for services rendered, a whole assortment of cost-containment strategies are being introduced in an effort to maintain some semblance of financial viability. Healthcare providers can approach cost control from two different angles. On the fixed-cost operational overhead side, traditional cost-containment techniques have focused on downsizing, maximizing productivity, staffing redesign, improved purchasing contracts, standardization, inventory control, and other more individualized restructured service models. On the variable-cost clinical side, cost control has been approached by introducing a variety of cost-containment strategies designed to improve efficiency and effectiveness of provider performance. While many of these strategies, previously discussed in the Journal of Healthcare Resource Management have stressed the importance of education, guidelines, pathways, and other clinical "tools for improvement," the success of many of these tools resides in the ability to provide real-time intervention. Real-time intervention rather than the more passive retrospective variance analysis has the greatest potential for producing cost savings by actually making a recommendation that prevents the unwanted event from occurring. In many institutions, the case manager bears the responsibility for monitoring and managing these programs. This article describes various case management models currently used by different institutions. 相似文献
27.
28.
Urethral duplication in the male: review of 16 cases 总被引:5,自引:0,他引:5
PURPOSE: Urethral duplication is a rare congenital anomaly. The clinical presentation varies because of the different anatomical patterns of this abnormality. We describe our experience with 16 male patients with this anomaly. MATERIALS AND METHODS: We retrospectively reviewed the records of 16 male patients treated for urethral duplication in the last 10 years. Age at presentation ranged from newborn to 8 years. Evaluation included ultrasound, voiding cystourethrography, retrograde urethrography and endoscopy. RESULTS: A blind ending duplicated urethra (type I) was present in 4 patients, 2 independent urethras with distinct bladder necks (type IIA1) in 6, 2 urethras originating from a common bladder neck (type IIA2) in 4, and complete urethral and bladder duplication (type III) in 2. Six patients had associated vesicoureteral reflux. Duplication was an incidental finding at epispadias repair in 3 patients with bladder exstrophy, at hypospadias repair in 1 and at hydrocele repair in 1. One patient with bilateral dysplastic kidneys died in the newborn period. Surgical management included excision of the duplicated urethra in 8 cases and urethroplasty using a pedicle flap in 2, while surgical management was not required in 3. CONCLUSIONS: Urethral duplication is a rare congenital anomaly with a variable clinical presentation. This pathological condition may easily be under diagnosed, especially in patients with other associated anomalies, such as hypospadias or bladder exstrophy. Surgical management should be planned individually according to the anatomical findings of the abnormality. 相似文献
29.
S Gananadha TDB Yan J Zhao P Clingan D Glenn DL Morris 《Journal of Medical Imaging and Radiation Oncology》2005,49(5):396-399
Hepatic artery infusion (HAI) chemotherapy is associated with higher response rates compared to systemic chemotherapy in those patients with unresectable liver malignancies. Operative hepatic artery catheter (HAC) insertion has significant morbidity and mortality, especially in patients with high‐volume disease, some of whom may not respond to HAI chemotherapy. We report our experience in 45 patients with high‐volume liver disease who were initially treated with HAI chemotherapy via a radiologically placed temporary HAC to try to select the responders who then went on to have an operative HAC. In these 45 patients who had 62 radiologically placed HAC, we found very few major complications, and certainly no complications such as cholecystitis, vascular or malperfusion problems. 相似文献
30.
Sáenz DA Turjanski AG Sacca GB Marti M Doctorovich F Sarmiento MI Estrin DA Rosenstein RE 《Journal of pineal research》2002,33(1):31-36
In the present work, the effect of melatonin on the hamster retinal nitridergic pathway was examined. When the retinas were incubated in the presence of low concentrations (1 pM-10 nM) of melatonin for 15 min, a significant decrease of nitric oxide synthase (NOS) activity was observed. However, when crude retinal homogenates were preincubated with melatonin for 15 min, no changes in NOS activity were detected, despite the fact that under the same conditions trifluoperazine, a calmodulin inhibitor, significantly decreased enzymatic activity. Kinetic analysis showed that melatonin decreased the V(max) of retinal NOS without changes in the K(m). On the other hand, low concentrations (100 pM) of melatonin significantly reduced retinal L-arginine influx. A decrease in the V(max) of L-arginine uptake was observed in the presence of melatonin, whereas the K(m) remained unchanged. Melatonin significantly inhibited the accumulation of cyclic guanosine monophosphate (cGMP) levels induced by both L-arginine and sodium nitroprusside (SNP). In summary, the present results indicate that melatonin could be a potent inhibitor of the retinal nitridergic pathway. 相似文献