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991.
Liver cancer and gastric cancer are the most common solid tumors worldwide. Transforming growth factor-beta (TGF-beta) production and lack of response to TGF-beta growth inhibitory effects have been associated with tumor progression and therapeutic resistance. HepG2, Hep3B, and SK-HEP-1 human liver cancer lines produce 3, 5.7, and 2.5 ng TGF-beta1; 1.4, 2, and 4 ng TGF-beta2 and 0.15, 0.2 and 0.22 ng TGF-beta3 per 107 cells (24 h). Expression of the TGF-beta type I receptor is 20x, 1x, and 0.6x the level in mink lung MvLu1 cells in the HepG2, Hep3B, and SK-HEP-1 cells, respectively. HepG2 and Hep3B cells do not express the TGF-beta type II receptor while SK-HEP-1 cells express 7x the level found in mink lung MvLu1 cells. Hs 746T, KATO III, RF-1, and RF-48 human gastric cancer cell lines produce 12. 5, 0.35, 0.4, and 0.4 ng TGF-beta1; 2.6, 0.95, 0.5, and 0.52 ng TGF-beta2 and 0.42, 0.17, 0.12, and 0.14 ng TGF-beta3 per 107 cells (24 h). Expression of TGF-beta type I receptor is 0.7x, 0.7x, 0.8x, 0.6x the level in mink lung MvLu1 cells in the Hs 746T, KATO III, RF-1 and RF-48 cells, respectively. KATO III cells are lacking in the TGF-beta type II receptor while Hs 746T, RF-1 and RF-48 cells express 10x, 0.8x, and 1x the levels in mink lung MvLu1 cells. The IC50 for TGF-beta1 is >10 ng/ml in all of these lines except RF-48 where TGF-beta1 is mitogenic. The response of the cell lines to radiation, doxorubicin, mitomycin C, cisplatin, 5-fluorouracil, methotrexate, and gemcitabine showed that SK-HEP-1 was the most drug resistant liver cancer cell line and KATO III was the most drug resistant gastric cancer cell line. Overall, there was no correlation between TGF-beta secretion in cell culture and sensitivity of the cells to anticancer agents. Increased TGF-beta1 levels were detectable in the plasma of nude mice bearing Hep3B and Hs 746T xenografts. Those tumors which secreted greater amounts of TGF-beta were more therapeutically resistant in vivo.  相似文献   
992.
Abstract Arsenic trioxide, believed to be a carcinogen and a teratogen, has found its niche in the treatment of acute promyelocytic leukemia (APL). APL is a disease affecting young patients. Post-treatment fertility and outcome of pregnancy are always a concern in a disease with high cure rates. We report a case series of six patients who were treated successfully for APL with arsenic trioxide and who parented at least one healthy offspring after completing their treatment.  相似文献   
993.
Tumor oxygen status is a reliable prognostic marker that impacts malignant progression and outcome of tumor therapy. However, tumor oxygenation is heterogeneous and cannot be sufficiently described by a single parameter. It is influenced by several factors including microvessel density (MVD), blood flow (BF), blood volume (BV), blood oxygen saturation, tissue pO(2), oxygen consumption rate, and hypoxic fraction. The goal of this investigation was to integrate these measurements to obtain a comprehensive profile of tumor oxygenation. Platelet/endothelial cell adhesion molecule immunohistochemistry, the recessed oxygen microelectrode, color and power Doppler ultrasound (DUS), and diffuse light spectroscopy (DLS) were used to measure tumor oxygen status using vascular endothelial growth factor (VEGF)-transfected hypervascular human melanoma xenografts and their nontransfected counterparts as a model. NIH1286 human melanoma cells were transfected with a retroviral vector +/- a 720-bp fragment of human VEGF(121). High VEGF-producing clones were selected by ELISA. Oxygen consumption rate was measured in NIH1286/VEGF+ [VEGF-transfected cells (VEGF+ cells)] and NIH1286/Vec cells [cells transfected with vector alone (Vec cells)] using a standard Clark oxygen electrode. Athymic nude 6-8-week-old mice received s.c. injection in the right flank with 5 x 10(6) VEGF+ or Vec cells. When tumors were 10-14 mm in maximum dimension, serum was analyzed for VEGF by ELISA. Cryopreserved tumor tissue sections were immunostained for platelet/endothelial cell adhesion molecule, and MVD measurements were made. Tumor-bearing mice were anesthetized, and pO(2) measurements were made using Eppendorf pO(2) histograph or the recessed oxygen microelectrode. Tumor BF and BV were measured by quantitative analysis of DUS images. DLS was used to measure tumor BF and blood oxygen saturation variation. VEGF+ cell supernatants had 15,500 pg/ml VEGF, and Vec cells had 10 pg/ml. VEGF+ and Vec cells had equivalent oxygen consumption rates. VEGF+ tumors had a faster growth rate than Vec tumors. Serum from VEGF+ tumor-bearing mice showed 4,211 pg/ml VEGF, whereas VEGF was undetectable in the serum of control mice. MVD values were 74 +/- 11 in VEGF+ tumors and 39 +/- 4 in control tumors at x200 magnification/0.95-mm(2) area. The median pO(2) values were 3.5-fold higher in VEGF+ tumors than in Vec tumors by the recessed oxygen microelectrode and 18-fold higher by Eppendorf pO(2) histograph. DUS showed a 3.3-fold higher mean BF and a 5.5-fold higher BV in VEGF+ tumors than in Vec tumors. DLS showed a 3.2-fold higher mean BF and 1.7-fold higher oxygen saturation in the hypervascular tumors as compared with the control tumor type, consistent with increased BF and BV data by DUS. An integrated approach that yields a comprehensive and consistent profile of oxygen status in tumors could potentially provide critical information for prognosis and treatment.  相似文献   
994.
BACKGROUND: Syphilis can affect the anterior as well as the posterior segment of the eye at any stage. HISTORY AND SIGNS: A 52-year-old man was referred to our clinic because of acute loss of his vision and hearing. Best corrected visual acuity (BCVA) was counting fingers (CF) right and 0.05 left eye, respectively. Fundoscopy revealed bilateral intraretinal macular haemorrhages and a large yellowish edematous lesion involving macula and midperipheral retina. Fluorescein angiography showed diffuse late edema. The visual field showed a defect corresponding to the edematous lesion. The "Ganzfeld" electroretinogram (ERG) was markedly reduced and the multifocal ERG in the affected area was not recordable. THERAPY AND OUTCOME: VDRL, FTA-Abs and TPHA tests in serum and cerebrospinal fluid were positive. Intravenous penicillin therapy was initiated. BCVA, visual field and ERG eventually recovered completely. CONCLUSIONS: Syphilis should be considered as a differential diagnosis in any unclear inflammatory ocular condition. Awareness of syphilitic posterior placoid chorioretinitis allows rapid diagnosis and therapy.  相似文献   
995.
PURPOSE: The aim of this case-control study was to investigate the relationship between homocysteine (tHcy), 5,10 methylene tetrahydrofolate reductase (MTHFR) C677T genotype, folate and vitamin B12 status, and retinal vein occlusion (RVO). METHODS: Subjects with RVO (n = 106) were recruited from outpatient and inpatient sources. Controls (n = 98) were selected to achieve a similar age and sex distribution. Full ocular examination was performed and medical history was taken for each study participant. Plasma and serum samples were analyzed for tHcy level and folate and vitamin B12 status, and extracted DNA was assessed for the MTHFR C677T genotype. RESULTS: There was no significant difference in plasma tHcy level or thermolabile MTHFR allele frequency between subjects and controls. Similarly, there was no significant difference in folate or vitamin B12 status between subjects and controls. MTHFR genotype did not affect folate or vitamin B12 concentrations in subjects or controls. However, tHcy was significantly higher in thermolabile homozygotes than in nonthermolabile homozygotes (ratio of geometric means, 1.35; 95% confidence interval [CI], 1.04-1.74; P = 0.024). CONCLUSIONS: Hyperhomocysteinemia, the MTHFR C677T mutation, and folate and vitamin B12 status are not important risk factors for RVO in this population.  相似文献   
996.
OBJECTIVE: Evaluation of the clinical profile and distribution of different sub-types of amblyopia in a referral eye hospital in India. METHODS: This was a prospective hospital-based observational study, evaluating the clinical profile of patients with amblyopia presenting to a referral strabismology practice. The examination included assessment of the visual acuity, the refractive status, the fixation pattern, the grade of binocularity, and evaluation of the associated strabismus, if any before treatment was started. RESULTS: The average age of the patients at presentation was 7.97?6.18 years with 81 out of 683 patients (11.8%) presenting above the age of 20 years. The best-corrected visual acuity (BCVA) was less than 6/60 in the amblyopic eye in 121 out of 733 eyes (16.5%). Strabismic amblyopia was the most common sub-type of amblyopia seen (274/733 eyes, 37.38%). Though patients with anisometropic amblyopia presented at a later age (average of 10.03+/-6.92 years), they had better visual acuity, binocular functions, and centricity of fixation at all ages, relative to other sub-types of amblyopia. The BCVA did not show any co-relation with the age of presentation [co-relation co-efficient (CF) of 0.074], refractive status of the amblyopic eye (CF of 0.078), the type of amblyopia (CF of 0.196), or the type of strabismus present (CF of 0.079). However, a very significant co-relation was seen between the BCVA and the fixation pattern of the amblyopic eye (CF of 0.817). CONCLUSIONS: Lack of knowledge and awareness about amblyopia and its appropriate timely management has been the main cause for the late presentations and significant visual impairment associated with the condition.  相似文献   
997.
PURPOSE: To describe the methodology and baseline data for the Antioxidants in Prevention of Cataracts (APC) study in South India. METHODS: The APC study is a prospective, 5-year, randomized, triple-masked, placebo-controlled, field-based clinical trial to examine the effect of antioxidants (combination tablet of vitamins A, C, and E) on progression of cataract. The primary outcome variable is cataract progression (nuclear opalescence), evaluated with the slit-lamp biomicroscope by the Lens Opacification Classification System III method. Secondary outcome variables are progression in cortical and posterior subcapsular opacity and nuclear color, change in best corrected visual acuity, myopic shift, and treatment failure (progression to cataract surgery or best corrected vision worse than 20/400 in an eye). Inclusion criteria are age between 35 and 50 years and best-corrected visual acuity of 20/40 or better. Exclusion criteria are a diagnosis of diabetes mellitus or nonfasting blood glucose level>7.8 mmol/L, history or presence of various ocular conditions or treatment forms, or current use of vitamin supplements. Baseline ophthalmic, demographic, and potential cataract risk factor data (such as smoking, sunlight, or alcohol exposure) were compared between groups on an intent-to-treat basis. RESULTS: Of 954 people screened, 798 were enrolled, a sample size which exceeded the required estimate. More than 80% of subjects had 20/20 or better vision in at least one eye, and baseline prevalence of significant cataract according to the LOCS III grading scale was high. The two treatment groups were comparable for all baseline measures except alcohol intake. CONCLUSION: The sample size and group baseline characteristics will provide sufficient power to detect a change in cataract progression within 5 years.  相似文献   
998.
As several important policy questions remain regarding the use of medical abortion in developing countries, we investigated the safety, efficacy, and acceptability of mifepristone-misoprostol abortion in the outpatient family planning departments of two urban hospitals and one rural hospital in India. Nine-hundred women (with gestations of < or =63 days in the urban sites and < or =56 days in the rural site) received 600 mg mifepristone followed 48 h later by 400 microg oral misoprostol in the clinic. Four point four percent or fewer urban women and 1.0% rural women were lost to follow-up. Perfect and typical-use failure rates were low at all sites. While rural women reported fewer side effects at all sites, the vast majority of women were satisfied with their medical abortions. Medical abortion can be offered safely, effectively, and acceptably in the outpatient family planning departments of urban and rural hospitals in India.  相似文献   
999.
The effects of lethal (50 ppm) and sublethal (5 ppm) concentrations of CdCl2 on the liver of the freshwater teleost Tilapia mossambica were studied by routine histological techniques. Engorged blood vessels, congestion, vacuolar degeneration of hepatocytes, necrosis of pancreatic cells, and fatty changes in the peripancreatic hepatocytes were the pathological alterations observed in liver.  相似文献   
1000.
A comparison has been made of Lapudrine (chlorproguanil) and Maloprim (pyrimethamine +dapsone) as malaria chemoprophylactics when given every two weeks for 3 years to Gambian children under the age of 5 years. Both drugs produced falls in spleen and malaria parasite rates and an increase in packed cell volume. Maloprim, but not chlorproguanil, significantly reduced the incidence of episodes of fever accompanied by malaria parasitaemia. Children who received Maloprim, but not those who received chlorproguanil, grew better than children in the placebo group. This finding suggests that brief clinical episodes of malaria are more important in impairing growth than more prolonged periods of asymptomatic parasitaemia. No serious side-effect attributable to either drug was observed. After chemoprophylaxis had been given for 3 malaria transmission seasons the level of resistance of Plasmodium falciparum to pyrimethamine and to chlorproguanil was about 10%.  相似文献   
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