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31.
Chronic hepatic injury results in liver fibrosis with eventual progression to irreversible cirrhosis. Liver fibrogenesis involves the activation of the quiescent hepatic stellate cell into an activated myofibroblast that is characterized by α-smooth muscle actin (α-SMA) expression and the production of collagens (types I and III). In the present study, rats were randomly divided into three groups: (i) control group, where rats were only treated with a vehicle; (ii) fibrosis group, where rats were treated with carbon tetrachloride (CCl(4)) to induce liver fibrosis; and (iii) silymarin group, where rats were protected with silymarin during CCl(4) treatment. Rats were sacrificed and sections of liver tissue were counterstained with hematoxylin and eosin and Masson's trichrome. Other sections were immunostained using collagens and α-SMA primary antibodies. Fibrosis was confirmed using serum marker measurements. Microscopic images of the stained sections were acquired and digitized. The Biomarker Index of Fibrosis (BIF) was calculated from the images by quantifying the percentage of stained fibers. Statistical methods of texture analysis (TA), namely co-occurrence and run-length matrices, were applied on the digital images followed by classification using agglomerative hierarchical clustering and linear discriminant analysis with cross validation. TA applied on different biomarkers was successful in discriminating between the groups, showing 100% sensitivity and specificity for classification between the control and fibrosis groups using any biomarker. Some classification attempts showed dependence on the biomarker used, especially for classification between the silymarin and fibrosis groups, which showed optimal results using Masson's trichrome. TA results were consistent with both BIF and serum marker measurements.  相似文献   
32.
Abstract Prays oleae Bern, (OM) and Palpita unionalis Hüb., (JM) are two of the most important pests in olive groves in Egypt. A 3‐year monitoring study using sex pheromone traps in semi‐arid and arid olive groves was performed. In the semi‐arid grove, flight pattern of the OM was the same as in other Mediterranean countries, but in dates concordating plant phenology. The moth completes three generations annually: the first flight is in March to April, the second is in May to June and the third occurs in August to October. In the arid olive grove, an interesting flight pattern was observed. First flight was always very close or overlapped with the second one with no male catches during August to October. However, eggs were present most of the season, indicating unusually high female presence and oviposition activity of the OM during the absence of males in the traps. Generally, moth densities were significantly lower in low fruiting years than in higher ones and were also lower in the arid olive grove than in the semi‐arid one. In contrast, JM males were present all season, exhibiting six to seven and three to four overlapping flight peaks in arid and semi‐arid olive groves, respectively. Moth densities were significantly higher in the arid olive grove than those in the semi‐arid one. This study shows that trapping location and fruit bearing year are characteristics that strongly affect the grove‐specific information needed to estimate correctly adult emergence and thus the timing of control measures.  相似文献   
33.
Novel biocomposites were fabricated by impregnating β-tricalcium phosphate (β-TCP)/zirconia particles into the polymers matrix. The composite materials were characterized using thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) analyzes and Scanning Electron Microscopy (SEM). The results confirmed the conversion of hydroxyapatite (HA) to β-TCP at a sintering temperature of 1150 °C with or without zirconia powder. The in vitro behavior was assessed via measurement of calcium and phosphorus ions in SBF (simulated body fluid). FT-IR and SEM of the composites were performed pre and post immersion in SBF. The results prove that the bone like apatite layer formation was enhanced on the β-TCP-Z20/polymeric composite surface more than that on the β-TCP-Z10/polymeric composite. Therefore, the data confirmed that zirconia plays an important role in the enhancement of the apatite formation. The conclusions proved that the β-TCP-Z20/polymeric biocomposites, containing 20% of zirconia, are promising for bone remodeling applications.  相似文献   
34.
Photoperiod and thermosensitive genetic male sterile (PTGMS) lines have become one of the main sources of global rice production increasing. This study was conducted to evaluate the fertility alteration and validate the male sterility genes using validation markers in novel Egyptian Indica and Japonica PTGMS lines under natural conditions. The study revealed that the new genetic male sterile lines belong to the type of photo–thermosensitive genetic male sterility (PTGMS). The fertility alteration of these lines has influenced by photoperiod and temperature interaction. The new PTGMS lines have three sensitive periods of fertility alteration; transformation, sterility, and fertility period. Furthermore, the sensitive stage of fertility transformation might be from secondary branch primordial to pollen mother cells (PMC) meiosis. Under the natural Sakha condition, the new PTGMS lines were stable sterile under the condition of day length upper 13,75 h and temperature over 25 °C, while its convert to fertile under day length under 13 h, and temperature lower than 24 °C. The co-dominant markers identified the pms3 and tms5 genes in the new PTGMS lines, indicated that the fertility alteration in these lines controlled by photoperiod and thermosensitive stages.  相似文献   
35.
In order to identify quantitative trait loci (QTLs) for leaf senescence and related traits in rice (Oryza sativa L.), we developed two backcross populations, indica/japonica// japonica and indica/japonica//indica, using IR36 as the indica parent and Nekken-2 as the japonica parent. The QTLs were mapped using a set of simple sequence-repeat markers (SSRs) in the BC1F1 population. Senescence was characterized in these plants by measuring the leaf chlorophyll content 25 days after flowering (DAF), the reduction in chlorophyll content (the difference between the chlorophyll content at flowering and at 25 DAF), and the number of late-discoloring leaves per panicle at 25 DAF in five plants from each BC1F2 line. These plants were moved into a temperature-controlled growth cabinet at the time of flowering and allowed to mature under identical conditions. Eleven QTLs were detected in the two populations. The major of QTLs for senescence were found on the short arm of chromosome 6 and on the long arm of chromosome 9. Of these, one QTL on chromosome 6 and two on chromosome 9 were verified by confirming the effects of the genotypes on the phenotypes of the BC1F3 lines. The japonica parent was found to contribute to late senescence at all but one QTL. Based on a comparison of the effects of heterozygotes and homozygotes on the phenotypic values of each QTL genotype, we concluded that the differential senescence observed in the indica-japonica hybrid was not due to over-dominance; rather, it was the result of partial-dominance genes that were donated from either of the parents.  相似文献   
36.
Cancer is the second leading cause of death worldwide. Conventional therapies cause serious side effects and, at best, merely extend the patient's lifespan by a few years. Cancer control may therefore benefit from the potential that resides in alternative therapies. There is thus an increasing demand to utilize alternative concepts or approaches to the prevention of cancer. In this report, we show a potential protective effect of Fenugreek seeds against 7,12-dimethylbenz(alpha)anthracene (DMBA)-induced breast cancer in rats. At 200 mg/kg b.wt., Fenugreek seeds' extract significantly inhibited the DMBA-induced mammary hyperplasia and decreased its incidence. Epidemiological studies also implicate apoptosis as a mechanism that might mediate the Fenugreek's anti-breast cancer protective effects. To our knowledge, this is the first study that suggests significant chemopreventive effects of Fenugreek seeds against breast cancer.  相似文献   
37.
38.
BACKGROUND: Low grade fibromyxoid sarcoma has been fully described histologically; however, the fine needle aspiration (FNA) cytologic findings are scantily defined, and the distinction from other benign and malignant soft tissue tumors can be difficult. CASE: We examined FNA cytologic material from a slowly growing, large chest wall mass in a 28-year-old woman. The surgical specimen was processed for routine histology and immunohistochemical studies. The cytologic smears were adequately cellular, showing spindly cells with uniform, elongated nuclei; small, inconspicuous nucleoli; and scanty, wispy cytoplasm associated with myxoid material. No significant nuclear pleomorphism or mitoses were noted. The excised tumor was well circumscribed, focally infiltrating the surrounding muscles. The cut surface was variable, featuring fibrous, solid, fleshy and myxoid areas. Microscopically, the solid, fibrous areas displayed increased cellularity with storiform, intersecting and parallel patterns. In the myxoid areas the cells grew in a haphazard fashion and appeared floating in abundant mucoid matrix associated with a capillary vascular network similar to the chicken-wire pattern seen in cases of myxoid liposarcoma. The tumor cells were spindly, with fusiform, uniform nuclei. Focal, moderate nuclear pleomorphism was noted. The mitotic index was low. The tumor cells were positive for vimentin, alpha-1-antitrypsin and lysozyme and negative for S-100, actin, desmin and CD34. CONCLUSION: Although low grade fibromyxoid sarcoma is a rare neoplasm, it should be recognized and distinguished from other soft tissue tumors because of its low malignant potential. The definitive FNA cytologic diagnosis can be challenging but is possible if the tumor is adequately sampled, with multiple passes from different areas. Clinical and radiologic correlations are of great help. All spindle cell tumors with myxoid changes, such as myxoid liposarcoma, myxofibrosarcoma, cellular myxoma, myxoid leiomyosarcoma and peripheral nerve sheath tumors, should be considered in the differential diagnosis. In contrast to the cytologic features, the histologic findings are characteristic and well established.  相似文献   
39.
BACKGROUND: Systemic Lupus Erythematosus (SLE) is an autoimmune disease characterized by a wide variety of autoantibodies, some of which are pathogenic. In recent years it has become more evident that the polyclonal B cell activation in SLE is T-cell dependent. The stimulation of the autoantibody producing B cells is likely mediated by the TH2 subtype of T cells producing IL-4, IL-5, IL-6 and IL- 10, whereas the TH1 subtype secreting IL-2 and IFN-gamma predominates in cell-mediated immune response. Tumor Necrosis Factor (TNF-alpha) is both a proinflammatory and an immunoregulatory cytokine. TNF-alpha has differential effects on B cells, on T cells and on dendritic cells as well as on the process of programmed cell death. Understanding how the immune system integrates the pleiotropic properties of TNF-alpha is a challenge, particularly so in diseases like SLE. Meanwhile the role of IL-6 in the pathogenesis of SLE is controversial. Objective: To investigate whether serum levels of TNF-alpha and IL-6 is higher in Egyptian patients with SLE than healthy control volunteers and its correlation with the clinical activity in patients with different activity scores as measured by Systemic Lupus Erythmatosus Disease Activity Index (SLEADI). Methods: Sixty individuals (40 patients with Systemic lupus Erythmatosus and 20 healthy control volunteers) were the subject of this study, they were subjected to thorough clinical examination, laboratory investigations, their clinical disease activity was scored according to SLEDAI, and serum sampling was obtained for TNF-alpha and IL-6 levels assay. Renal biopsy was carried out and examined by light microscopy by a pathologist blinded with the clinical activity. Results: The mean level of TNF-alpha was (766.95+/-357.82Pg/ml) for patients with active disease while it was (314.01+/-100.87Pg/ml) for those with inactive disease and (172.7+/-39.19Pg/ml) for the healthy control group. The difference was statistically significant (P=.002). The mean level of IL-6 was (135.4+/-54.23Pg/ml) for patients with active disease while it was (47.33+/-18.61Pg/ml) for those with inactive disease and (21.15+/-10.99Pg/ml) for the healthy control group. The difference was statistically significant (P=.002). A significant correlations between TNF-alpha and IL-6 serum levels and the SLEDAI score was observed (r=.743 and .772, respectively). Conclusion: Serum TNF-alpha and IL-6 are sensitive markers of SLE disease activity. They may be useful independent markers for prediction of SLE disease activity and to differentiate normal subjects from those having SLE. Possible therapeutic implications in the treatment of SLE in the future deserve wide scale trials.  相似文献   
40.
Treatment with 1-4 microM As(2)O(3) slightly induced apoptosis in U-937 human promonocitic leukemia cells. This effect was potentiated by co-treatment with MEK/ERK (PD98059, U0126) and JNK (SP600125, AS601245) inhibitors, but not with p38 (SB203580, SB220025) inhibitors. However, no potentiation was obtained using lonidamine, doxorubicin, or cisplatin instead of As(2)O(3). Apoptosis potentiation by mitogen-activated protein kinase (MAPK) inhibitors involved both the intrinsic and extrinsic executionary pathways, as demonstrated by Bax activation and cytochrome c release from mitochondria, and by caspase-8 activation and Bid cleavage, respectively; and the activation of both pathways was prevented by Bcl-2 over-expression. Treatment with MEK/ERK and JNK inhibitors, but not with p38 inhibitors, caused intracellular glutathione (GSH) depletion, which was differentially regulated. Thus, while it was prevented by N-acetyl-L-cysteine (NAC) in the case of U0126, it behaved as a NAC-insensitive process, regulated at the level of DL-buthionine-(S,R)-sulfoximine (BSO)-sensitive enzyme activity, in the case of SP600125. The MEK/ERK inhibitor also potentiated apoptosis and decreased GSH content in As(2)O(3)-treated NB4 human acute promyelocytic leukemia (APL) cells, but none of these effects were produced by the JNK inhibitor. MEK/ERK and JNK inhibitors did not apparently affect As(2)O(3) transport activity, as measured by intracellular arsenic accumulation. SP600126 greatly induced reactive oxygen species (ROS) accumulation, while BSO and U0126 had little or null effects. These results, which indicate that glutathione is a target of MAP kinases in myeloid leukemia cells, might be exploited to improve the antitumor properties of As(2)O(3), and provide a rationale for the use of kinase inhibitors as therapeutic agents.  相似文献   
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