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21.
To learn and teach about HIV/AIDS is to enter complex and senstitive territory that at times may be personally challenging. 5 In the vast literature on HIV infection and nursing two main themes recur: nurses' lack of understanding, negative attitudes and anxieties related to HIV/AIDS and the need for education to change such attitudes and enhance nurses' knowledge and skills. 相似文献
22.
Kallikrein 4 expression is up-regulated in epithelial ovarian carcinoma cells in effusions 总被引:1,自引:0,他引:1
Davidson B Xi Z Klokk TI Tropé CG Dørum A Scheistrøen M Saatcioglu F 《American journal of clinical pathology》2005,123(3):360-368
We immunohistochemically analyzed kallikrein 4 protein (hK4) expression in patients with epithelial ovarian carcinoma (181 malignant effusions and 103 solid carcinoma lesions). Expression of hK4 was also studied in 32 effusions using immunoblotting. Carcinoma cells expressed hK4 in 144 (79.6%) of 181 effusions and 85 (82.5%) of 103 solid tumors. Expression was seen in 51% or more of tumor cells in 70 effusions but often was limited to 5% or fewer cells in solid tumors (P = .009, primary tumors vs effusions; P = .002, metastases vs effusions). Immunoblotting showed hK4 expression in 31 of 32 specimens. Stromal cell hK4 expression, seen in 48 (46.6%) of 103 lesions, was significantly higher in primary tumors than metastases (26/43 vs 22/60, P = .019). hK4 expression in tumor cells was significantly lower in International Federation of Gynecology and Obstetrics stage IV than stage III tumors (P = .004, all lesions; P = .012, primary tumors). hK4 expression in carcinoma cells was associated with longer overall survival (not significant; P = .14, peritoneal effusions). hK4 is expressed widely in ovarian carcinoma; levels in carcinoma cells are highest in effusions, which might be related to loss of stromal contribution and/or altered microenvironment. hK4 expression in carcinoma cells of effusions or solid tumors does not predict survival. 相似文献
23.
Chan YB Miguel-Aliaga I Franks C Thomas N Trülzsch B Sattelle DB Davies KE van den Heuvel M 《Human molecular genetics》2003,12(12):1367-1376
Autosomal recessive spinal muscular atrophy (SMA) is linked to mutations in the survival motor neuron (SMN) gene. The SMN protein has been implicated at several levels of mRNA biogenesis and is expressed ubiquitously. Studies in various model organisms have shown that the loss of function of the SMN gene leads to embryonic lethality. The human contains two genes encoding for SMN protein and in patients one of these is disrupted. It is thought the remaining low levels of protein produced by the second SMN gene do not suffice and result in the observed specific loss of lower motor neurons and muscle wasting. The early lethality in the animal mutants has made it difficult to understand why primarily these tissues are affected. We have isolated a Drosophila smn mutant. The fly alleles contain point mutations in smn similar to those found in SMA patients. We find that zygotic smn mutant animals show abnormal motor behavior and that smn gene activity is required in both neurons and muscle to alleviate this phenotype. Physiological experiments on the fly smn mutants show that excitatory post-synaptic currents are reduced while synaptic motor neuron boutons are disorganized, indicating defects at the neuromuscular junction. Clustering of a neurotransmitter receptor subunit in the muscle at the neuromuscular junction is severely reduced. This new Drosophila model for SMA thus proposes a functional role for SMN at the neuromuscular junction in the generation of neuromuscular defects. 相似文献
24.
Kok Yvette J.M.de; Merkx Gerard F.M.; van der Maarel Silvere M.; Huber Irene; Malcolm Susan; Ropers Hans-Hilger; Cremers Frans P.M. 《Human molecular genetics》1995,4(11):2145-2150
X-linked deafness with stapes fixation (DFN3) is caused by mutationsin the POU3F4 gene at Xq21.1. By employing pulsed field gelelectrophoresis (PFGE) we identified a chromosomal aberrationin the DNA of a DFN3 patient who did not show alterations inthe open reading frame (ORF) of POU3F4. Southern blot analysisindicated that a DNA segment of 150 kb, located 170 kb proximalto the POU3F4 gene, was duplicated. Fluorescence in situ hybridization(FISH) analysis, PFGE, and detailed Southern analysis revealedthat this duplication is part of a more complex rearrangementincluding a paracentric inversion involving the Xq21.1 region,and presumably the Xq21.3 region. Since at least two DFN3-associatedminideletions are situated proximal to the duplicated segment,the inversion most likely disconnects the POU3F4 gene from aregulatory element which is located at a distance of at least400 kb upstream of the POU3F4 gene. 相似文献
25.
26.
Molecular and genetic characterization of human cell lines resistant tol-asparaginase and albizziin 总被引:1,自引:0,他引:1
Irene L. Andrulis Rhodora Argonza A. Elizabeth L. Cairney 《Somatic Cell and Molecular Genetics》1990,16(1):59-65
Human cell lines resistant tol-asparaginase or albizziin were isolated by multistep selection of HT1080 fibrosarcoma and MIA PaCa-2 pancreatic carcinoma cells. Mutants were cross-resistant to both drugs, but more resistant to the drug used for selection. The drug-resistant cell lines expressed elevated levels of asparagine synthetase activity and protein, up to 17-fold over that of the parental cells. Enzyme overproduction was due to gene amplification in the albizziin-resistant cells, whereas increased expression without amplification was observed inl-asparaginase-resistant cells. 相似文献
27.
Rensink AA Otte-Höller I de Boer R Bosch RR ten Donkelaar HJ de Waal RM Verbeek MM Kremer B 《Neurobiology of aging》2004,25(1):93-103
Amyloid-beta (Abeta) deposition in the cerebral arterial and capillary walls is one of the characteristics of Alzheimer's disease and hereditary cerebral hemorrhage with amyloidosis-Dutch type. In vitro, Abeta1-40, carrying the "Dutch" mutation (DAbeta1-40), induced reproducible degeneration of cultured human brain pericytes (HBP), by forming fibrils at the cell surface. Thus, this culture system provides an useful model to study the vascular pathology seen in Alzheimer's disease. In this study, we used this model to investigate the effects of insulin on Abeta-induced degeneration of HBP, as it has been mentioned previously that insulin is able to protect neurons against Abeta-induced cell-death. The toxic effect of DAbeta1-40 on HBP was inhibited by insulin in a dose-dependent matter. Insulin interacted with Abeta and inhibited fibril formation of Abeta in a cell-free assay, as well as at the cell surface of HBP. Our data indicate that the formation of a fibril network is essential for Abeta-induced cell death in HBP. Additionally, insulin may be involved in the regulation of Abeta fibrillization in AD. 相似文献
28.
X-linked mixed deafness (DFN3): cloning and characterization of the critical region allows the identification of novel microdeletions 总被引:5,自引:0,他引:5
Huber Irene; Bitner-Gllndzicz Maria; de Kok Yvette J.M.; van der Maarel Silvere M.; Ishikawa-Brush Yumiko; Monaco Anthony P.; Robinson David; Malcolm Susan; Pembrey Marcus E.; Brunner Han G.; Cremers Frans P.M.; Ropers Hans-Hilger 《Human molecular genetics》1994,3(7):1151-1154
We have found that the microsatellite marker AFM207zg5 (DXS995)maps to all previously described deletions which are associatedwith X-linked mixed deafness (DFN3) with or without choroideremiaand mental retardation. Employing this marker and pHU16 (DXS26)we have identified two partially overlapping yeast artificialchromosome clones which were used to construct a complete 850kb cosmid contig. Cosmids from this contig have been testedby Southern blot analysis on DNA from 16 unrelated males withX-linked deafness. Two novel microdeletions were detected inpatients which exhibit the characteristic DFN3 phenotype. Bothdeletions are completely contained within one of the known DFN3-deletions,but one of them does not overlap with two previously describeddeletions in patients with contiguous gene syndromes consistingof DFN3, chorolderemia, and mental retardation. Assuming thatonly a single gene is involved, this suggests that the DFN3gene spans a chromosomal region of at least 400 kb. 相似文献
29.
Central regulation of somatosensory signals has been extensively studied, but little is known about their regulation in the periphery. Given the widespread exposure of the skin sensory terminals to the environment, it is of interest to explore how somatosensory sensitivity is affected by changes in properties of the skin. In the leech, the annuli that subdivide the skin can be erected under the control of the annulus erector (AE) motoneurons. To analyze whether this surface change influences mechanosensory sensitivity, we studied the responses of low threshold mechanosensory T cells to mechanical stimulation of the skin as AE motoneurons were activated. In segments of the body wall connected to the corresponding ganglion and submerged in an aqueous environment, T cells responded to localized bubbling on the skin and to water flow parallel to its surface. Excitation of AE motoneurons diminished these responses in a way that depended on the motoneuron firing frequency. Video recordings established that the range of AE firing frequencies that produced effective annulus erection coincided with that influencing T cell responses. In isolated ganglia, AE firing had no effect on T cell excitability, suggesting that annulus erection diminished T cell responsiveness to mechanical input. Counteracting this effect, mechanosensory inputs inhibited AE motoneurons. However, because depolarization of AE cells caused a decrease in their input resistance, the more active the motoneuron, the less sensitive it became to inhibitory signals. Thus when brought to fire, AE motoneurons would stay "committed" to a high activity level, and this would limit sensory responsiveness to incoming mechanical signals. 相似文献
30.
Irene Held I. James Young 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1969,8(2):150-162
Summary After 3H-lysine was applied to the Xth and XIIth cranial nuclei, radioactive protein synthesized in the nerve cell bodies of the hypoglossal and vagus nerves moved down the axons of these fibers at maximal rates of 6.3±1.2 and 16±3 mm per day, respectively. The distribution of radiolabeled protein at various periods indicated that other proteinaceous components moved at slower velocities. 相似文献