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91.
92.
Thalidomide was used to treat acute (n=21) or chronic (n=59) graft-vs-host disease (GVHD) in 80 haematopoietic stem cell allograft recipients after failure to respond to the combination of cyclosporine and corticosteroids with or without other agents. The median time to onset of acute GVHD was 11 days, and thalidomide was started at a median of 48 days post transplant. In addition to corticosteroids and cyclosporine, 13 patients had also received other agents before thalidomide. None of the patients responded and all died of acute GVHD. For chronic GVHD (limited in 13, extensive in 46), thalidomide was started at a median of 385 days post transplant. In addition to corticosteroids and cyclosporine, 34 patients received azathioprine concomitantly. In all patients, thalidomide was added to the ongoing immunosuppressive regimen. The median duration of therapy with thalidomide was 60 days (range, 11-1210; <2 weeks in 11). In total, 13 patients (22%) had complete response, eight (14%) partial response and 38 (64%) no response. Response rates were comparable for limited (39%) and extensive (33%) chronic GVHD. At a median of 53 months, 19 patients are alive, 13 without evidence of chronic GVHD. Survival was significantly better in patients who responded to thalidomide. The principal causes of death were progressive chronic GVHD (n=29) and relapsed leukaemia (n=7). In conclusion, thalidomide has no activity in acute GVHD, but has some activity in chronic GVHD in combination with other agents.  相似文献   
93.
Lysophosphatidic acid (LPA) is an endogenous lipid growth factor that is thought to play important roles in cell proliferation and antiapoptosis and therefore may have roles in the development and progression of benign prostatic hyperplasia (BPH). CYR61 (CCN1), on the other hand, is a growth factor-inducible immediate early gene that functions in cell proliferation, differentiation, and extracellular matrix synthesis. Here we show the close relationship between LPA-induced expression of CYR61 and prostate enlargement. CYR61 mRNA and protein were dramatically up-regulated by 18:1 LPA (oleoyl-LPA) within 1 and 2 h, respectively, in both stromal and epithelial prostatic cells. G protein-coupled receptors, i.e. Edg-2, Edg-4, and Edg-7, for LPA were also expressed in both stromal and epithelial prostatic cells. Furthermore, on DNA microarray analysis for normal and BPH patients, CYR61 was found to be related to the development and progression of BPH, regardless of symptoms. Although CYR61 mRNA was synthesized in hyperplastic epithelial cells, in many cases of BPH, CYR61 protein was detected in both the epithelial and stromal regions of BPH patient tissues. The functional contribution of CYR61 to prostatic cell growth was demonstrated by recombinant CYR61 protein and anti-CYR61 neutralizing antibodies, which inhibited CYR61-dependent cell spreading and significantly diminished cell proliferation, respectively. In conclusion, these data support the hypothesis that LPAs induce the expression of CYR61 by activating G proteincoupled receptors and that CYR61 acts as a secreted autocrine and/or paracrine mediator in stromal and epithelial hyperplasia, demonstrating the potential importance of this signaling mechanism in the disease.  相似文献   
94.
Nair S  Ghosh K  Kulkarni B  Shetty S  Mohanty D 《Platelets》2002,13(7):387-393
Glanzmann's thrombasthenia is an autosomal recessive disorder, rare in a global context, but a relatively more common platelet function defect in communities where consanguineous marriages are more frequent. On clinical grounds alone, it cannot be distinguished from other congenital platelet function defects. Epistaxis, gum bleeding, menorrhagia are the common clinical manifestations, whereas large muscle hematoma or hemarthrosis seldom occur in these patients. Essential diagnostic features are a normal platelet count and morphology, a greatly prolonged bleeding time, absence of platelet aggregation in response to ADP, collagen, epinephrine, thrombin and to all aggregating agents which ultimately depend on fibrinogen binding to platelets for this effect, flow cytometry, studies of GPIIb-IIIa receptors on the platelet membrane surface using monoclonal antibodies. The present review describes some of the uncommon features of the disorders and the currently available options which the treating physicians should be aware of during the management of these patients. Although by definition all patients with Glanzmann's thrombasthenia have a virtually complete failure of platelet aggregation, a number of variant forms of GT have been described in which the glycoproteins are present in normal or near normal amounts but are functionally defective. Understanding the pathophysiology of the disorder by the treating physicians is of utmost importance. Presence of high affinity platelet receptors resulting in thrombasthennia-like phenotype may require an antagonistic treatment atypical of classical GT management. It has now been established that different genetic mutations of either GPIIb or IIIa genes results in such a heterogeneity of thrombasthenia phenotype. Glanzmann's thrombasthenia is a paradigm for treating coronary artery disease patients with GPIIb-IIIa antibody and inhibitors. By using these medicines we create a temporary GT-like situation. Hence, understanding this disease is of utmost importance to the practicing cardiologist. As mutations for different variant forms of GT become known, our understanding of how GPIIb-IIIa molecules can be activated to act as a receptor for fibrinogen molecules will be increased. Such understanding undoubtedly will help us to devise better drugs with GPIIb-IIIa inhibitors. Molecular biology techniques have enabled us to equivocally detect heterozygote carriers who are clinically asymptomatic. However, there may be several laboratories in the developing world, which have no access to molecular biology techniques. Development of more robust techniques of quantitation of platelet receptors has enabled an accurate diagnosis of heterozygote carriers or an unborn fetus in the second trimester. The importance of the GPIIb-IIIa polymorphisms in carrier and prenatal diagnosis has not been properly studied. Nowadays the less direct method of PLA1 typing (determination of the levels of platelet antigen) of the foetal platelets as early as 16 weeks of intrauterine life can be used for prenatal diagnosis of GT.  相似文献   
95.
Podocyte apoptosis as a pathway of podocyte loss is often suspected but rarely detected. To study podocyte apoptosis versus inflammatory forms of podocyte death in vivo, we targeted murine double minute (MDM)‐2 for three reasons. First, MDM2 inhibits p53‐dependent apoptosis; second, MDM2 facilitates NF‐κB signalling; and third, podocytes show strong MDM2 expression. We hypothesized that blocking MDM2 during glomerular injury may trigger p53‐mediated podocyte apoptosis, proteinuria, and glomerulosclerosis. Unexpectedly, MDM2 blockade in early adriamycin nephropathy of Balb/c mice had the opposite effect and reduced intra‐renal cytokine and chemokine expression, glomerular macrophage and T‐cell counts, and plasma creatinine and blood urea nitrogen levels. In cultured podocytes exposed to adriamycin, MDM2 blockade did not trigger podocyte death but induced G2/M arrest to prevent aberrant nuclear divisions and detachment of dying aneuploid podocytes, a feature of mitotic catastrophe in vitro and in vivo. Consistent with these observations, 12 of 164 consecutive human renal biopsies revealed features of podocyte mitotic catastrophe but only in glomerular disorders with proteinuria. Furthermore, delayed MDM2 blockade reduced plasma creatinine levels, blood urea nitrogen, tubular atrophy, interstitial leukocyte numbers, and cytokine expression as well as interstitial fibrosis. Together, MDM2‐mediated mitotic catastrophe is a previously unrecognized variant of podocyte loss where MDM2 forces podocytes to complete the cell cycle, which in the absence of cytokinesis leads to podocyte aneuploidy, mitotic catastrophe, and loss by detachment. MDM2 blockade with nutlin‐3a could be a novel therapeutic strategy to prevent renal inflammation, podocyte loss, glomerulosclerosis, proteinuria, and progressive kidney disease. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
96.
The identification of the etiology of breast cancer is a crucial research issue for the development of an effective preventive and treatment strategies. Researchers are exploring the possible involvement of Mouse Mammary Tumor Virus (MMTV) in causing human breast cancer. Hence, it becomes very important to use a consistent positive control agent in PCR amplification based detection of MMTV-Like Sequence (MMTV-LS) in human breast cancer for accurate and reproducible results. This study was done to investigate the feasibility of using genomic DNA of MCF-7 breast cancer cells to detect MMTV-LS using PCR amplification based detection. MMTV env and SAG gene located at the 3′ long terminal repeat (LTR) sequences were targeted for the PCR based detection. No amplification was observed in case of the genomic DNA of MCF-7 breast cancer cells. However, the 2.7 kb DNA fragment comprising MMTV env and SAG LTR sequences yielded the products of desired size. From these results it can be concluded that Genomic DNA of MCF-7 cell is not a suitable choice as positive control for PCR or RT-PCR based detection of MMTV-LS. It is also suggested that plasmids containing the cloned genes or sequences of MMTV be used as positive control for detection of MMTV-LS.  相似文献   
97.
Abstracts     
Dental enamel is the most mineralized tissue of vertebrate organisms. Enamel biosynthesis is initiated by the secretion, processing, and self-assembly of a complex mixture of proteins. The formation of an ordered enamel organic extracellular matrix (ECM) seems be a crucial step for the proper formation of mineral phase. Polarizing microscopy demonstrates that the ordered supramolecular structure of the secretory-stage enamel organic ECM is strongly birefringent. In the present work we analyzed the birefringence of secretory-stage enamel organic ECM in amelogenin (Amelx)- and enamelysin (Mmp20)-deficient mice. Female Amelx+/? animals showed significant reduction in optical retardation values when compared with the Amelx+/+ subgroup (p = 0.0029). The secretory-stage enamel organic ECM of the Amelx?/? subgroup did not exhibit birefringence. The secretory-stage enamel organic ECM of Mmp20?/? mice showed a significant decrease in optical retardation as compared with Mmp20+/+ and Mmp20+/? mice (p = 0.0000). Mmp20+/? and Mmp20+/+ mice exhibited similar birefringence (p = 1.0000). The results presented here support growing evidence for the idea that the birefringence of secretory-stage enamel organic ECM is influenced by the ordered supramolecular organization of its components.  相似文献   
98.

Background:

Organ transplantation is the most preferred treatment modality for end-stage organ diseases. The need for the transplants is higher than the availability. Prerequisites for the success of transplantation program include awareness and positive attitudes.

Aim:

To assess the perceptions and attitudes of the people seeking health care in tertiary care centers towards organ donation in Mangalore, India.

Settings and Design:

This cross-sectional study included 863 people seeking general healthcare as outpatients.

Materials and Methods:

Face to face interviews were carried out using pretested tools which included the socio demographic data. Data was analyzed using Statistical Package for Social Sciences version 11.5.

Results:

Overall, 59.6% participants showed the willingness to donate organs. Females (64.1%) and participants from upper socio economic status (62.7%) had higher willingness rates for organ donations. Hindus (63.6%) and Christians (63.3%) had higher willingness rates for organ donations than Muslims (38.2%). Also, 23.7% participants showed willingness to donate eyes and 33.6% wished to donate any organ after death. Most of the participants (67%) were aware that money should not be accepted for donating organs, and 58.1% were aware that it is an offence to accept any benefit for organ donations. Forty percent participants had perceived risks associated with organ donation. Regarding donor cards, 42.3% of the participants knew about it and 3.7% already possessed it.

Conclusion:

It is apparent from the study that though there was high level of awareness about organ donation, a high proportion of the participants did not have positive attitudes towards organ donation.  相似文献   
99.
Journal of Digital Imaging - Retinopathy of prematurity (ROP) is a potentially blinding disorder seen in low birth weight preterm infants. In India, the burden of ROP is high, with nearly 200,000...  相似文献   
100.
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