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221.
Eliana Alves Liliana Costa Carla MB Carvalho Jo?o PC Tomé Maria A Faustino Maria GPMS Neves Augusto C Tomé José AS Cavaleiro ?ngela Cunha Adelaide Almeida 《BMC microbiology》2009,9(1):70
Background
In recent times photodynamic antimicrobial therapy has been used to efficiently destroy Gram (+) and Gram (-) bacteria using cationic porphyrins as photosensitizers. There is an increasing interest in this approach, namely in the search of photosensitizers with adequate structural features for an efficient photoinactivation process. In this study we propose to compare the efficiency of seven cationic porphyrins differing in meso-substituent groups, charge number and charge distribution, on the photodynamic inactivation of a Gram (+) bacterium (Enterococcus faecalis) and of a Gram (-) bacterium (Escherichia coli). The present study complements our previous work on the search for photosensitizers that might be considered good candidates for the photoinactivation of a large spectrum of environmental microorganisms. 相似文献222.
Melarkode S Ramakrishnan Anand Eswaraiah Tania Crombet Patricia Piedra Giselle Saurez Harish Iyer AS Arvind 《MABS-AUSTIN》2009,1(1):41-48
Nimotuzumab is a humanized therapeutic monoclonal antibody against epidermal growth factor receptor (EGFR). Clinical trials are ongoing globally to evaluate nimotuzumab in different indications. Nimotuzumab has been granted approval for use in squamous cell carcinoma of head and neck (SCCHN), glioma and nasopharyngeal cancer in different countries. This review focuses on the unique functional characteristics of nimotuzumab. Also, it discusses the safety and efficacy data obtained from the Phase IIb clinical trial conducted in India in SCCHN. Post marketing surveillance data from Cuba for the use of nimotuzumab in pediatric and adult glioma is also discussed. Overall, nimotuzumab has immense therapeutic potential in cancers of epithelial origin.Key words: nimotuzumab, EGFR, humanized, monoclonal antibody, SCCHN, glioma, overall survival 相似文献
223.
Mutations in TCF8 cause posterior polymorphous corneal dystrophy and ectopic expression of COL4A3 by corneal endothelial cells
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224.
Huang CC Stricher F Martin L Decker JM Majeed S Barthe P Hendrickson WA Robinson J Roumestand C Sodroski J Wyatt R Shaw GM Vita C Kwong PD 《Structure (London, England : 1993)》2005,13(5):755-768
The binding surface on CD4 for the HIV-1 gp120 envelope glycoprotein has been transplanted previously onto a scorpion-toxin scaffold. Here, we use X-ray crystallography to characterize atomic-level details of gp120 with this transplant, CD4M33. Despite known envelope flexibility, the conformation of gp120 induced by CD4M33 was so similar to that induced by CD4 that localized measures were required to distinguish ligand-induced differences from lattice variation. To investigate relationships between structure, function, and mimicry, an F23 analog of CD4M33 was devised. Structural and thermodynamic analyses showed F23 to be a better molecular mimic of CD4 than CD4M33. F23 also showed increased neutralization breadth, against diverse isolates of HIV-1, HIV-2, and SIVcpz. Our results lend insight into the stability of the CD4 bound conformation of gp120, define measures that quantify molecular mimicry as a function of evolutionary distance, and suggest how such evaluations might be useful in developing mimetic antagonists with increased neutralization breadth. 相似文献
225.
The proposed work describes a protocol for high-frequency in vitro regeneration through nodal segments and shoot tips in Decalepsis arayalpathra, a critically endangered medicinal liana of the Western Ghats. Nodal segments were more responsive than shoot tips in terms of shoot proliferation. Murashige and Skoog’s (MS) basal medium supplemented with 5.0 μM 6-benzyladenine (BA) was optimum for shoot initiation through both the explants. Among different combinations of plant growth regulators and growth additive screened, MS medium added with 5.0 μM BA + 0.5 μM indole-3-acetic acid + 20.0 μM adenine sulphate effectuated the highest response: 11.8 shoots per nodal segment and 5.5 shoots per shoot tip with mean shoot length of 9.2 and 4.8 cm, respectively. Half-strength MS medium with 2.5 μM α-naphthalene acetic acid was optimum for in vitro root induction. The plantlets with the well developed shoot and root were acclimatized in Soilrite? with 92 % survival rate in the field conditions. During acclimatization, chlorophyll content, net photosynthetic rate, stomatal conductance, and transpiration rate were gradually changed in dependence of formation of new leaves. Further, the changes in activities of antioxidant enzymes, i.e., superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) as well as activity of carbonic anhydrase were also observed: a continuous rise in SOD activity, but a rise and fall in the activities of CAT, APX, and GR were also noticed. Maximum fresh mass (3.1 g plant-1), dry mass (0.35 g plant-1) of roots and 2-hydroxy-4-methoxybenzaldehyde content of 9.22 μg cm-3(root extract) were recorded after 8 weeks of acclimatization. 相似文献
226.
Zishan Ahmad Anwar Shahzad Shiwali Sharma Shahina Parveen 《Plant Cell, Tissue and Organ Culture》2018,132(3):497-510
To ensure replenishment, a refine protocol for micropropagation of Decalepis salicifolia (Bedd. ex Hook.f.) Venter a critically endangered and endemic medicinal plant was developed using mature nodal explants. A high frequency shoot regeneration system was obtained on Murashige and Skoog (MS) medium comprised of 6- benzyladenine (BA) (5.0 µM)?+?α-naphthalene acetic acid (NAA) (0.5 µM)?+?adenine sulphate (ADS) (30.0 µM) corresponds to a highest mean number of 9.97?±?0.01 shoots/explants with maximum shoot length of 6.46?±?0.1 cm. Successful rooting in microshoots was achieved on half strength MS medium supplemented with indole-3-butyric acid (IBA) (2.5 µM). A maximum of 6.10?±?0.07 roots/microshoot with average root length of 2.30?±?0.06 cm was obtained. As much as 90% plantlets survived when Soilrite? was used as planting substrate and finally established in soil without any casualty and morphological variation. Acclimatized plantlets were screened for pigment content, net photosynthetic rate (PN), stomatal conductance (Gs) and transpiration rate (E) during subsequent days of acclimatization as well as the changes in antioxidant was also evaluated. A steady rise was observed in the activity of superoxide dismutase (SOD) for initial 21 days and then after a decrease was found showing improved acclimatization efficiency of the plant. Similarly, the activities of catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) enzyme shows reliable increase as the days of acclimatization advanced which play their precautionary role against oxidative damage to the plant. The genetic fidelity of the in vitro raised plantlets with that of mother plant was further confirmed using random amplified polymorphic DNA (RAPD) and inters simple sequence repeats (ISSR) analysis. Additionally, the effect of acclimatization on the biosynthesis of 2-hydroxy-4-methoxybenzaldehyde (2H4MB) in the root system was also evaluated in relation to their biomass production. Maximum fresh weight (4.9 g/plant), dry weight (0.65 g/plant) of roots and 2H4MB content (6.8 µg ml?1 of root extract) was obtained after 10 weeks of acclimatization. Accelerated multiplication rate with the stability of genetic virtue, physiological and biochemical parameter assure the efficacy of the protocol developed for the propagation of this critically endangered medicinal plant. 相似文献
227.
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229.
Parisa Naeem Adi Baumgartner Nader Ghaderi Farshid Sefat Maysa Alhawamdeh Saeed Heidari Fanila Shahzad Karthic Swaminathan Pouria Akhbari Mohammad Isreb Diana Anderson Andrew Wright Mojgan Najafzadeh 《Journal of cellular and molecular medicine》2023,27(2):222-231
Incidence of Malignant Melanoma has become the 5th in the UK. To date, the major anticancer therapeutics include cell therapy, immunotherapy, gene therapy and nanotechnology-based strategies. Recently, extracellular vesicles, especially exosomes, have been highlighted for their therapeutic benefits in numerous chronic diseases. Exosomes display multifunctional properties, including inhibition of cancer cell proliferation and initiation of apoptosis. In the present in vitro study, the antitumour effect of cord blood stem cell (CBSC)-derived exosomes was confirmed by the CCK-8 assay (p < 0.05) on CHL-1 melanoma cells and improve the repair mechanism on lymphocytes from melanoma patients. Importantly, no significant effect was observed in healthy lymphocytes when treated with the exosome concentrations at 24, 48 and 72 h. Comet assay results (OTM and %Tail DNA) demonstrated that the optimal exosome concentration showed a significant impact (p < 0.05) in lymphocytes from melanoma patients whilst causing no significant DNA damage in lymphocytes of healthy volunteers was 300 μg/ml. Similarly, the Comet assay results depicted significant DNA damage in a melanoma cell line (CHL-1 cells) treated with CBSC-derived exosomes, both the cytotoxicity of CHL-1 cells treated with CBSC-derived exosomes exhibited a significant time-dependent decrease in cell survival. Sequencing analysis of CBSC exosomes showed the presence of the let-7 family of miRNAs, including let-7a-5p, let-7b-5p, let-7c-5p, let-7d-3p, let-7d-5p and two novel miRNAs. The potency of CBSC exosomes in inhibiting cancer progression in lymphocytes from melanoma patients and CHL-1 cells whilst causing no harm to the healthy lymphocytes makes it a potential candidate as an anticancer therapy. 相似文献
230.
OI Klychnikov AV Drabkin OV Vasilenko YS Pavlov MS Trofimova IN Smolenskaya AA Rozenkranz AS Sobolev AV Babakov 《Biochemistry. Biokhimii?a》1998,63(9):1083-1089
Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex. 相似文献