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71.
Mouse models in liver cancer research: A review of current literature   总被引:3,自引:0,他引:3  
Primary liver cancer remains one of the most lethal malignancies worldwide. Due to differences in prevalence of etiological factors the incidence of primary liver cancer varies among the world, with a peak in East-Asia. As this disease is still lethal in most of the cases, research has to be done to improve our understanding of the disease, offering insights for possible treatment options. For this purpose, animal models are widely used, especially mouse models. In this review, we describe the different types of mouse models used in liver cancer research, with emphasis on genetically engineered mice used in this field. We focus on hepatocellular carcinoma (HCC), as this is by far the most common type of primary liver cancer, accounting for 70%-85% of cases.  相似文献   
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Background: Extended‐release naltrexone (XR‐NTX) is a once‐a‐month injectable formulation for the treatment of alcohol dependence previously shown to reduce drinking and heavy drinking relative to placebo ( Garbutt et al., 2005 ). A 24‐week, randomized, double‐blind, placebo‐controlled study established the efficacy and safety of XR‐NTX in this patient population. In this report, the effect of XR‐NTX on quality of life (QOL) was examined. Methods: Alcohol‐dependent patients were randomly assigned to receive XR‐NTX 380 mg (N = 205), XR‐NTX 190 mg (N = 210), or placebo (N = 209), combined with a standardized psychosocial intervention. QOL was assessed using the Medical Outcomes Study 36‐item short‐form health survey, administered at baseline and at 4‐week intervals during 24 weeks of treatment. Results: Compared with U.S. population norms, patients showed initial impairment in the health‐related QOL domains of mental health, social functioning, and problems with work or other daily activities due to emotional problems. Adherence to all 6 injections was 65% for XR‐NTX 190 mg, 63% for XR‐NTX 380 mg, and 64% for placebo. Generalized estimating equations analyses using an intention‐to‐treat sample revealed that XR‐NTX 380 mg was associated with significantly greater improvements from baseline in mental health (p = 0.0496), social functioning (p = 0.010), general health (p = 0.048), and physical functioning (p = 0.028), compared with placebo. Linear regression analyses revealed that reductions from baseline in drinking (percentage of drinking days and percentage of heavy drinking days in the last 30 days) were significantly (p < 0.05) correlated with improvements in quality of life. Conclusion: Extended‐release naltrexone 380 mg in combination with psychosocial intervention was associated with improvements in QOL, specifically in the domains of mental health, social functioning, general health, and physical functioning.  相似文献   
74.
p16INK4A and p15INK4B gene deletions in primary leukemias   总被引:4,自引:0,他引:4  
The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses. The ALL cases showed a relatively high frequency of homozygous deletions (22%, 6 of 27) at the p16INK4A gene locus. Interestingly, of the six cases with p16INK4A homozygous deletions, only three showed homozygous deletions at the p15INK4B gene. In 81 CLL patients, we detected one homozygous and five heterozygous deletions at both the p16INK4A and p15INK4B genes and two heterozygous deletions at the p16INK4A gene alone. Deletion of these two genes in AML cases is relatively low (9%). We did not detect deletions in any of the MDS, HCL, and CML cases examined. Sequence analyses of p16INK4A gene of six CLL cases with heterozygous deletion at this locus showed a 27-bp deletion at the splice acceptor site of intron 1 in one case and changes in the coding sequence in three other cases. The data presented in this report showed that (1) p16INK4A and p15INK4B genes are preferentially deleted homozygously in ALL and heterozygously in CLL cases with frequent mutation in the second allele, and (2) p16INK4A gene appears to be more frequently deleted than p15INK4B gene.  相似文献   
75.
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant.  相似文献   
76.
The purpose of this report was to evaluate scintigraphy analysis of Southern blot hybridization as a method to quantify the breakpoint cluster region (BCR) rearrangement of Philadelphia chromosome (Ph)+ chronic myelogenous leukemia (CML). Cytogenetic and molecular studies performed simultaneously on 474 bone marrow and/or blood samples from 300 patients treated with alpha-interferon-based therapy were compared. Molecular results were expressed as the percentage of rearranged BCR bands versus the total scintigraphic signal. The percentage of Ph+ metaphases was calculated on 25 metaphases. The results of molecular studies obtained on both peripheral blood and bone marrow samples were identical. The rank correlation between the BCR quantification and the percentage of Ph positivity in 465 samples was excellent (r = .78). However, of 99 samples with a normal karyotype, 24% had a BCR rearrangement. Of 86 samples with no BCR rearrangement, 13% showed a Ph chromosome. Of 49 samples with partial cytogenetic remission (Ph+ metaphases, 1% to 34%), 23% had no BCR rearrangement. In samples with a minor or no cytogenetic response (Ph+ metaphases, > 34%), BCR analysis overestimated the degree of response in 73 of 326 samples (22%). Nevertheless, survival analysis by BCR quantification level showed statistically better outcome for patients in complete or partial molecular response (P < .01). Molecular quantification of BCR was useful in monitoring the course of Ph+ CML. This method, which can be used on peripheral blood, detected residual disease not shown by cytogenetic analysis and was prognostically relevant as a measure of disease suppression.  相似文献   
77.
Previous studies on the association of ankylosing spondylitis and abnormalities of the lung parenchyma have been based largely on plain radiography and pulmonary function testing. This study, although uncontrolled, is the first to use high-resolution computed tomography to examine the entire lung parenchyma in ankylosing spondylitis patients, and to correlate the findings with clinical assessment, plain radiography and pulmonary function testing. The study population comprised 26 patients meeting the New York criteria for idiopathic ankylosing spondylitis who attended the out-patient department at our institution. High-resolution computed tomography examination revealed abnormalities in 19 patients (70%): these included interstitial lung disease (n = 4), bronchiectasis (n = 6), emphysema (n = 4), apical fibrosis (n = 2), mycetoma (n = 1) and non-specific interstitial lung disease (n = 12). Plain radiography was abnormal in only four patients and failed to identify any patient with interstitial lung disease. All patients with interstitial lung disease on high-resolution computed tomography had respiratory symptoms and three of the four had evidence of a restrictive process on pulmonary function testing. This study raises, for the first time, the possible association between interstitial lung disease and ankylosing spondylitis, and highlights the use of high-resolution computed tomography in detecting such disease in ankylosing spondylitis patients.   相似文献   
78.
Fifty-one patients with previously untreated or minimally treated chronic myelogenous leukemia in chronic phase received human alpha interferon 3 to 9 X 10(6) units intramuscularly (IM) daily until complete hematologic remission, then at doses ranging from 3 X 10(6) units every other day to 9 X 10(6) units daily. Forty-one (80%) patients achieved a hematologic response, 36 (71%) of them attaining a complete hematologic remission with normal peripheral WBC and differential counts. Responding patients showed continuous but slow normalization of several other blood and marrow parameters including platelet counts, serum lactic dehydrogenase and B12 levels, and marrow cellularity and maturation index. Suppression of the Philadelphia chromosome on serial cytogenetic studies of marrow metaphases was documented in 20 of the 36 patients who achieved complete hematologic remission (56%; 39% of total group), eight of whom (22%) had a decrease of the Philadelphia chromosome-positive metaphases to less than 35%. These changes were persistent for 6 months or longer in 18 patients, seven of whom had continuous suppression of the Philadelphia chromosome to less than 90% for a median of 30+ months (range 21+ to 39+ months). After a median follow-up period of 37 months, 25 patients remain in continued disease control with interferon therapy. The projected 3-year survival rate is 76%, with a yearly death rate of 6%, 9%, and 9% in the first 3 years. Response, Philadelphia chromosome suppression, and survival were significantly better among patients in the low-risk category compared to intermediate- and high-risk categories, as defined by a multivariate analysis-derived prognostic model. The projected 3- year survival rate was 94% for patients who achieved a complete hematologic remission on interferon therapy and 45% for those who did not. Thirteen patients have developed blastic crisis, six with lymphoid and three with undifferentiated morphology. We conclude that human leukocyte alpha interferon effectively controls chronic myeloid leukemia and allows reappearance of diploid hemopoietic cells in some patients.  相似文献   
79.
This is a case series and review of the literature adding11 new cases.Coronary-cameral fistulas(CCFs)are infrequent anomalies which are in general co-incidentally found during diagnostic coronary angiography(CAG).To delineate the characteristics of congenital and acquired CCFs in adults,we performed a PubMed search for papers dealing with congenital or acquired CCFs in adults.Publications on coronary-vascular fistulas or paediatric subjects were not included.From the world literature,a total of 243 adult patients were identified who had congenital(65%)or acquired(35%)CCFs.In this review,which is part one of a two-part series on CCFs,we describe and discuss the congenital fistulas,give an overview on the published literature and report details of our own series of 11 patients with MMFs and solitary macro CCFs.Of the congenital group,56%were small or large solitary macro CCFs(cut-off 1.5mm)and 9%were coronary artery-ventricular multiple micro-fistulas(MMFs).Apical hypertrophic cardiomyopathy was reported in some of the reviewed subjects with MMFs(3/24=13%)but not was seen in our own series.Conservative medical management was generally the treatment of choice in congenital MMFs;prophylactic implantable cardioverter defibrillators(ICD)were implanted in 2/24(8%)of subjects,especially when extensive micro-fistulisations were involved.None of the patients of our own series required an ICD,as the MMFs were of limited size.Congenital or acquired CCFs in adults are infrequent anomalies having a wide spectrum of clinical presentation may varies from asymptomatic to severely devastating states requiring different treatment modalities.  相似文献   
80.
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