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51.
Mohammed
H. Hassan Sawsan Abuhamdah Mohamed Abdel-Bary Mohammed Wahman Tarek
Hamdy Abd-Elhamid Morris Beshay Karam Mosallam Bakheet
E.M. Elsadek 《Bioscience reports》2021,41(1)
Survivin is an inhibitor of apoptosis as well as a promoter of cell proliferation. Fibulin-3 is a matrix glycoprotein that displays potential for tumor suppression or propagation. The present study aimed to validate the expression levels of survivin and fibulin-3 in benign and malignant respiratory diseases. This case–control study included 219 patients categorized into five groups. Group A included 63 patients with lung cancer, group B included 63 patients with various benign lung diseases, group D included 45 patients with malignant pleural mesothelioma (MPM), and group E included 48 patients with various benign pleural diseases. Group C included 60 healthy individuals (control group). Serum survivin and fibulin-3 levels were measured by ELISA, whereas their nuclear expressions in the lung and pleura were assessed via Western blot analysis. The results showed significantly higher survivin serum levels and significantly lower fibulin-3 levels in group A compared with in group B and controls (P<0.001). There were significantly higher serum levels of survivin and fibulin-3 in group D compared with in group E and controls (P<0.001), consistent with observed nuclear survivin and fibulin-3 expression levels. Fibulin-3 was determined to have higher value than survivin in discriminating lung cancer from MPM (P<0.05). Survivin and fibulin-3 could be useful diagnostic markers for lung and pleural cancers, and fibulin-3 expression was particularly useful in differentiating lung cancer from MPM. 相似文献
52.
Modulation of retroviral restriction and proteasome inhibitor-resistant turnover by changes in the TRIM5alpha B-box 2 domain 下载免费PDF全文
Diaz-Griffero F Kar A Perron M Xiang SH Javanbakht H Li X Sodroski J 《Journal of virology》2007,81(19):10362-10378
An intact B-box 2 domain is essential for the antiretroviral activity of TRIM5alpha. We modeled the structure of the B-box 2 domain of TRIM5alpha based on the existing three-dimensional structure of the B-box 2 domain of human TRIM29. Using this model, we altered the residues predicted to be exposed on the surface of this globular structure. Most of the alanine substitutions in these residues exerted little effect on the antiretroviral activity of human TRIM5alphahu or rhesus monkey TRIM5alpharh. However, alteration of arginine 119 of TRIM5alphahu or the corresponding arginine 121 of TRIM5alpharh diminished the abilities of the proteins to restrict retroviral infection without affecting trimerization or recognition of the viral capsid. The abilities of these functionally defective TRIM5alpha proteins to accelerate the uncoating of the targeted retroviral capsid were abolished. Removal of the positively charged side chain from B-box 2 arginines 119/120/121 resulted in diminished proteasome-independent turnover of TRIM5alpha and the related restriction factor TRIMCyp. However, testing of an array of mutants revealed that the rapid turnover and retroviral restriction functions of this B-box 2 region are separable. 相似文献
53.
Background
Phytophthora infestans (Mont.) de Bary, the causal organism of late blight, is economically the most important pathogen of potato and resistance against it has been one of the primary goals of potato breeding. Some potentially durable, broad-spectrum resistance genes against this disease have been described recently. However, to obtain durable resistance in potato cultivars more genes are needed to be identified to realize strategies such as gene pyramiding or use of genotype mixtures based on diverse genes.Results
A major resistance gene, Rpi-rzc1, against P. infestans originating from Solanum ruiz-ceballosii was mapped to potato chromosome X using Diversity Array Technology (DArT) and sequence-specific PCR markers. The gene provided high level of resistance in both detached leaflet and tuber slice tests. It was linked, at a distance of 3.4 cM, to violet flower colour most likely controlled by the previously described F locus. The marker-trait association with the closest marker, violet flower colour, explained 87.1% and 85.7% of variance, respectively, for mean detached leaflet and tuber slice resistance. A genetic linkage map that consisted of 1,603 DArT markers and 48 reference sequence-specific PCR markers of known chromosomal localization with a total map length of 1204.8 cM was constructed.Conclusions
The Rpi-rzc1 gene described here can be used for breeding potatoes resistant to P. infestans and the breeding process can be expedited using the molecular markers and the phenotypic marker, violet flower colour, identified in this study. Knowledge of the chromosomal localization of Rpi-rzc1 can be useful for design of gene pyramids. The genetic linkage map constructed in this study contained 1,149 newly mapped DArT markers and will be a valuable resource for future mapping projects using this technology in the Solanum genus. 相似文献54.
Drosophila atonal (ato) is the proneural gene of the chordotonal organs (CHOs) in the peripheral nervous system (PNS) and the larval and adult photoreceptor organs. Here, we show that ato is expressed at multiple stages during the development of a lineage of central brain neurons that innervate the optic lobes and are required for eclosion. A novel fate mapping approach shows that ato is expressed in the embryonic precursors of these neurons and that its expression is reactivated in third instar larvae (L3). In contrast to its function in the PNS, ato does not act as a proneural gene in the embryonic brain. Instead, ato performs a novel function, regulating arborization during larval and pupal development by interacting with Notch. 相似文献
55.
Robert Mason Helen C. Dearden Bella Nguyen Jennifer A. Soon Jessica Louise Smith Manreet Randhawa Andrew Mant Lydai Warburton Serigne Lo Tarek Meniawy Alexander Guminski Phillip Parente Sayed Ali Andrew Haydon Georgina V. Long Matteo S. Carlino Michael Millward Victoria G. Atkinson Alexander M. Menzies 《Pigment cell & melanoma research》2020,33(2):358-365
The combination of ipilimumab and nivolumab is a highly active systemic therapy for metastatic melanoma but can cause significant toxicity. We explore the safety and efficacy of this treatment in routine clinical practice, particularly in the setting of serine/threonine‐protein kinase B‐Raf (BRAF)‐targeted therapy. Consecutive patients with unresectable stage IIIC/IV melanoma commenced on ipilimumab and nivolumab across 10 tertiary melanoma institutions in Australia were identified retrospectively. Data collected included demographics, response and survival outcomes. A total of 152 patients were included for analysis, 39% were treatment‐naïve and 22% failed first‐line BRAF/MEK inhibitors. Treatment‐related adverse events occurred in 67% of patients, grade 3–5 in 38%. The overall objective response rate was 41%, 57% in treatment‐naïve and 21% in BRAF/MEK failure patients. Median progression‐free survival was 4.0 months (95% CI, 3.0–6.0) in the whole cohort, 11.0 months (95% CI, 6.0‐NR) in treatment‐naïve and 2.0 months (95% CI, 1.4–4.6) in BRAF/MEK failure patients. The combination of ipilimumab and nivolumab can be used safely and effectively in a real‐world population. While first‐line efficacy appears comparable to trial populations, BRAF‐mutant patients failing prior BRAF/MEK inhibitors show less response. 相似文献
56.
Almas Fakhrah Hassan Adeel Bibi Arfa Ali Masab Lateef Sadia Mahmood Tariq Rasheed Awais Quraishi Umar Masood 《Plant and Soil》2018,431(1-2):371-387
Plant and Soil - Extreme climate events, including flooding and prolonged drought, may establish long-lasting (legacy) effects on soil abiotic and biotic properties, potentially influencing soil... 相似文献
57.
Biological control of streptococcal infection in Nile tilapia Oreochromis niloticus (Linnaeus, 1758) using filter‐feeding bivalve mussel Pilsbryoconcha exilis (Lea, 1838) 下载免费PDF全文
F. Othman M. S. Islam E. N. Sharifah F. Shahrom‐Harrison A. Hassan 《Zeitschrift fur angewandte Ichthyologie》2015,31(4):724-728
Since bivalve mussels are able to graze heavily on bacteria, in this paper it is hypothesized that when mussels are cultured with fish, the filtering efficiency of the mussels will keep the bacterial population below a certain threshold and thus assist in reducing the risk of bacterial disease outbreaks. The ability of the filter‐feeding bivalve mussel Pilsbryoconcha exilis to control Streptococcus agalactiae was tested in a laboratory‐scale tilapia culture system. Juvenile Nile tilapia (Oreochromis niloticus), the bivalve mussel as well as the bacteria were cultured at different combinations using four treatments: treatment‐1: mussel and bacteria but no fish, treatment‐2: tilapia and mussel but no bacteria, treatment‐3: tilapia and bacteria but no mussel, and treatment‐4: tilapia, mussels, and bacteria. All treatments were run in three replicates; stocking rates were 10 tilapia juveniles; five mussels; and about 3.5 × 105 colony forming units (CFU) ml?1 of bacteria in 50‐L aquaria with 40‐L volume. The mussel reduced the bacterial population by 83.6–87.1% in a 3‐week period whereas in the absence of the mussel, the bacterial counts increased by 31.5%. Oresence of the mussel also resulted in significantly higher growth and lower mortality of tilapia juveniles than when the mussel was absent. The results of this experiment suggest that the freshwater mussel P. exilis could control the population of S. agalactiae in a laboratory‐scale tilapia culture system. Future studies should focus on the dynamic interactions among fish, mussels, and bacteria as well as on how input such as feed and other organic materials affect these interactions. 相似文献
58.
59.
Mohamed Yara Ahmed Hassaneen H. M. El-Dessouky Mohamed A. Safwat Gehan Hassan Naglaa Abu-Mandil Amr Khalda 《Molecular biology reports》2021,48(7):5497-5502
Molecular Biology Reports - A cluster of many risk factors for type 2 diabetes and cardiovascular disease is used to describe the metabolic syndrome (MetS). Moreover, genetic differences associated... 相似文献
60.
M. Metwally M. el Sayed M. Osman P. P. F. Hanegraaf A. H. Stouthamer H. W. van Verseveld 《Antonie van Leeuwenhoek》1991,59(1):35-43
Aspergillus niger has been grown in glucose- and maltose-limited continuous cultures to determine the bioenergetic consequences of the production of the extracellular enzyme glucoamylase. Growth yields (g biomass per mol substrate) were high, indicating that growth was very efficient and protein production for biomass was not exceedingly energy consuming. It has been found that the energy costs for the production of this extracellular enzyme is very high. Depending on the efficiency of energy conservation the glucoamylase protein yield on ATP is between 1.3 and 2.6 g protein per mol ATP, which is equal or less than 10% of the theoretical maximum of 25.5. These high energy costs most probably have to be invested in the process of excretion. A comparison between an industrial over-producing strain and the wild typeAspergillus niger showed that this over-producing strain most probably is a regulatory mutant. Two regions of specific growth rates could be determined (one at specific growth rates lower and one at specific growth rates higher than 0.1 h-1), which are characterized by differences in mycelium morphology and a significant deviation from linearity in the linear equation for substrate utilization. Analysis of the region of specific growth rates higher than 0.1 h-1 yielded maintenance requirements of virtual zero. It has been concluded that for a good analysis of the growth behaviour of filamentour fungi the linear equation for substrate utilization is not suitable, since it contains no term for the process of differentiation. 相似文献