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151.
Mewani RR Tang W Rahman A Dritschilo A Ahmad I Kasid UN Gokhale PC 《International journal of oncology》2004,24(5):1181-1188
Raf-1 protein kinase plays an important role in cell growth, proliferation and cell survival. We have previously described the use of liposome-entrapped antisense raf oligonucleotide (LErafAON) to inhibit Raf-1 expression resulting in tumor growth inhibition and radiosensitization. The present study was undertaken to evaluate the chemosensitization effects of LErafAON in combination with doxorubicin or paclitaxel on a panel of human tumor xenografts. LErafAON (25.0 mg/kg i.v. x 10) displayed significant antitumor activity (P<0.05) when administered as a single agent in prostate (PC-3), lung (A549) and breast (MDA-MB 231) carcinoma models. Doxorubicin (1.0-4.0 mg/kg i.v. per week x 3) and paclitaxel (1.0-4.0 mg/kg i.v. on alternate days x 3) were administered as single agents at non-toxic doses that led to only minimal to moderate antitumor activity. However, a combination of LErafAON with doxorubicin or paclitaxel led to significantly enhanced antitumor activity in all the tumor types tested (PC-3, P<0.03; A549, P<0.035; MDA-MB 231, P<0.045) as compared with LErafAON alone or chemotherapeutic agents alone treated groups. This effect of chemosensitization appeared to be sequence-specific because a mismatch control oligonucleotide continued to show significant tumor growth. Additionally, no inhibition in Raf-1 expression in MDA-MB 231 tumor tissue was observed with mismatch oligonucleotide treatment. On the other hand, LErafAON treatment led to >75% inhibition of Raf-1 expression in tumor tissue. These preclinical observations support the use of LErafAON in combination with chemotherapeutic agents to improve the treatment of human cancers. 相似文献
152.
Chemotherapy-induced and/or radiation therapy-induced oral mucositis--complicating the treatment of cancer 总被引:3,自引:0,他引:3 下载免费PDF全文
The term mucositis is coined to describe the adverse effects of radiation and chemotherapy treatments. Mucositis is one of the most common adverse reactions encountered in radiation therapy for head and neck cancers, as well as in chemotherapy, in particular with drugs affecting DNA synthesis (S-phase-specific agents such as fluorouracil, methotrexate, and cytarabine). Mucositis may limit the patient's ability to tolerate chemotherapy or radiation therapy, and nutritional status is compromised. It may drastically affect cancer treatment as well as the patient's quality of life. The incidence and severity of mucositis will vary from patient to patient. It will also vary from treatment to treatment. It is estimated that there is 40% incidence of mucositis in patients treated with standard chemotherapy and this will not only increase with the number of treatment cycles but also with previous episodes. Similarly, patients who undergo bone marrow transplantation and who receive high doses of chemotherapy have a 76% chance of getting mucositis. Patients receiving radiation, in particular to head and neck cancers, have a 30% to 60% chance. The exact pathophysiology of development is not known, but it is thought to be divided into direct and indirect mucositis. Chemotherapy and/or radiation therapy will interfere with the normal turnover of epithelial, cells leading to mucosal injury; subsequently, it can also occur due to indirect invasion of Gram-negative bacteria and fungal species because most of the cancer drugs will cause changes in blood counts. With the advancement in cytology, a more precise mechanism has been established. With this understanding, we can select and target particular mediators responsible for the mucositis. Risk factors such as age, nutritional status, type of malignancy, and oral care during treatment will play important roles in the development of mucositis. Many treatment options are available to prevent and treat this condition, but none of them can completely prevent or treat mucositis. More and more pathological methods are being developed to understand this condition so that better therapeutic regimens can be selected. Emphasis also should be made in assessing the patient's psychologic condition, particular depressive disorders. This is important because treatment with antidepressants will not only contribute in lifting depression but also reduces pain somatization. Although mucositis is rarely life-threatening, it will interfere with treatment of cancer to a great extent. 相似文献
153.
The Cytomorphological features of Papillary Cystic Acinic Cell Carcinoma a rare malignant tumor of the Parotid gland in a 77 years male is described. The differential diagnosis and prognostic features are discussed. 相似文献
154.
A new glycoprotein allergen/antigen with the protease activity from Aspergillus fumigatus 总被引:1,自引:0,他引:1
BACKGROUND: Aspergillus fumigatus is an opportunistic fungus causing allergic and invasive aspergillosis in humans and animals. It secretes an array of complex biologically active glycoprotein antigens and allergens. It is important to identify and characterize probable potential virulent factors playing a major role in the pathogenesis of aspergillosis. METHODS: Using protein purification techniques (lectin affinity chromatography, gel filtration, electroelution and high-pressure liquid chromatography), a major antigen/allergen with a molecular weight of 56 kD (gp56) from A. fumigatus was purified to homogeneity. The protein was characterized by immunoblot, ELISA and protease assays. The N-terminal amino acid sequencing was performed. RESULTS: The gp56 protein showed a single band on silver staining and isoelectric focussing. The protein to carbohydrate ratio was 1.5:1 and gp56 gave a protein band at a molecular weight of 34 kD on enzymatic deglycosylation. It also exhibited IgG and IgE immunobinding with antibodies present in sera of allergic bronchopulmonary aspergillosis patients. The gp56 exhibited protease activity and N-terminal seven-amino acid sequence showed homology with fungal serine proteases. CONCLUSIONS: The gp56 protein by virtue of its proteolytic activity could be one of the virulent factors of A. fumigatus involved in establishing infection in the host along with other factors. 相似文献
155.
Escherichia coli causes the vast majority of urinary tract infections (UTI) in both ambulatory and hospital patients. Several uropathogenic virulence factors have been identified, but half of all E. coli isolates that cause UTI have none or only one of the known virulence factors. Thus, it is reasonable to presume that other bacterial factors may be important in UTI pathogenesis. In order to find additional uropathogenic E. coli genes, we used genomic subtraction to identify DNA regions present in a uropathogenic strain of E. coli (1128-11). Genomic subtraction yielded 40 tester-specific fragments, including a novel heat-resistant agglutinin (hra) gene fragment. hra occurred in 55% of 486 UTI strains compared to 28% of 165 rectal strains (P = 0.001). The hra gene in 1128-11 was cloned, sequenced, and found to have 91% homology to the hra gene from E. coli meningitis strain RS218. The genetic organization of genes flanking hra in 1128-11 is distinct from the hra found in E. coli strains J96 and RS218. In our UTI and rectal specimen collections, hra was positively associated with a number of known virulence genes, including pathogenicity island genes hly and cnf, which are absent in 1128-11. The presence of hra in 1128-11 independent of hly/cnf suggests multiple mechanisms by which hra can be acquired by pathogenic E. coli strains. The flanking genes suggest that in 1128-11, hra may be part of a novel variant of a pathogenicity island V. 相似文献
156.
Krishnan US 《Indian journal of pediatrics》2002,69(6):501-505
Congenital heart disease in the newborn is a unique and complex problem faced by both pediatricians and cardiologists as it
requires skillful handling and balancing of both neonatal issues as well as cardiac physiology. Babies with cyanotic and acyanotic
heart disease are physiologically different from each other and management has to be tailored to the individual diagnosis
and clinical status. Rapid diagnosis and appropriate management is the key to reducing mortality and morbidity in this fragile
patient population. The following review deals with the common presentations of heart problems in a newborn baby and methods
of diagnosis, investigative modalities, recent advances and approach to management 相似文献
157.
Das UM Nagarathna Arathi 《Journal of the Indian Society of Pedodontics and Preventive Dentistry》2002,20(3):98-101
Unerupted primary teeth is very rare especially in the maxillary anterior teeth. A case of unerupted left maxillary Cuspid due to the presence of compound composite odontoma in a 10 years old female child is presented. 相似文献
158.
In the present study significantly increased lipid peroxidation value (LPP) after a single intraperitioneal injection of lead acetate (LA) (100 mg/kg b.w.) indicated enormous generation of Reactive Oxygen Species (ROS). Lead-induced ROS has a direct inhibitory effect on the growth and differentiation of the spermatogonial cells showing a significant decline in sperm count. Chromosomal analysis of the primary spermatocytes at week 4 post-treatment in lead-treated mice revealed significantly higher no of aberrant cells including chromosomal deficiency, autosomal and XY-asynapsis plates compared to untreated control mice, Sperm morphology studies at week 1-4 and at week 8 post-treatment, indicated higher percentage of deformed sperm population compared to vehicle injected groups of mice. Supplementation of vitamin C (Vit C) at a dose of 10 mg/kg body weight to lead-treated mice groups, however, significantly reduced the LPP with a concomitant increase in sperm count, marked decrease in the no of aberrant cells and significant decline in the percentage of morphologically abnormal sperm population. Protective role of Vit C in combating lead-induced oxidative stress in mice testicular cells, has been discussed. 相似文献
159.
Abugreen S Muldrew KA Stevenson MR VanLeeuwen R DeJong PT Chakravarthy U 《The British journal of ophthalmology》2003,87(3):307-311
AIM: To examine the relation between the type of choroidal neovascularisation (CNV) in the first eye and age related maculopathy (ARM) severity in the fellow eye. METHODS: Colour fundus photographs and fluorescein angiograms from 67 subjects with a clinical diagnosis of CNV in one eye were scrutinised. CNV was classified as wholly classic, predominantly classic, minimally classic, or occult based on the proportion of classic leakage within the lesion. ARM changes in the fellow eye were assigned a severity stage using the system described by the Rotterdam Eye Study. Logistic regression analysis was employed to examine the association between CNV subtype and ARM stage. RESULTS: Of subjects with classic or predominantly classic CNV in the first eye 78% exhibited least no or early ARM features in the fellow eye. By contrast, 85% of subjects with minimally classic or occult CNV in the first eye exhibited more advanced ARM features in the fellow eye. Kruskall-Wallis one way ANOVA by ranks showed that this was highly significant (p = 0.002). Logistic regression analysis showed that as the proportion of occult CNV increased in the first eye, fellow eyes of subjects in this category were more likely to have been assigned to a higher ARM stage (p = 0.019). The area occupied by the CNV in the first eye also influenced severity of ARM changes in the fellow eye. CONCLUSION: The type and extent of CNV in the first affected eye has a distinct relation to ARM severity in the fellow eye. Fellow eyes of subjects with minimally classic or occult CNV in the first affected eye show widespread ARM changes suggestive of retinal pigment epithelial dysfunction. These findings suggest that classic CNV may be focal disease while occult CNV is essentially a more widespread retinal pigment epithelial disorder. 相似文献
160.
Identification of lesion components that influence visual function in age related macular degeneration 下载免费PDF全文
Hogg R Curry E Muldrew A Winder J Stevenson M McClure M Chakravarthy U 《The British journal of ophthalmology》2003,87(5):609-614
AIMS: To explore the relation between lesion composition as assessed by fundus photography and fluorescein angiography with clinical measures of vision in eyes of patients with age related macular degeneration (AMD). METHODS: A standardised visual function assessment along with colour stereo pair fundus photography was carried out in both eyes of 58 subjects with a confirmed clinical diagnosis of AMD. The size, location, and composition of the macular lesion (blood, exudate, subretinal fluid, pigment, membrane, atrophy, and fibrosis) were measured on the colour photographs using computer assisted image analysis. Of the 58 subjects, 44 also had concurrent fluorescein angiography. Classic and occult choroidal neovascularisation (CNV), blood, blocked fluorescence, fibrosis, geographic atrophy, and the total area of abnormal fluorescence were measured. Multiple linear regression was used to examine the relation between clinical measures of vision and the location and extent of lesion components identified by both colour and fluorescein image capture. RESULTS: The composition of the macular lesion strongly influenced visual function, with atrophy (p=0.001) and fibrosis (p=0.002) accounting for most of the variation. When the location of the lesion with respect to the fovea was examined, fibrosis within the fovea significantly influenced all clinical measures of vision (p=0.008). The regression model selected the total area of abnormal fluorescence and a composite parameter (a semiquantitative measure of the following characteristics: atrophy, exudates, blood, and fibrosis ) from colour photography (r(2) =0.52) as the variables that explained most of the variation in clinical measures of vision. CONCLUSIONS: The composition and extent of the macular lesion strongly influences visual function in eyes with AMD. Both colour photography and angiography yielded information, which together explained considerably more of the variation in the clinical measures of vision than either on its own. 相似文献