31 research outputs found
A bilayered tissue engineered in vitro model simulating the tooth periodontium
Due to the complexity of the structure of the tooth periodontium, regeneration of the full tooth attachment is not a trivial task. There is also a gap in models that can represent human tooth attachment in vitro and in vivo. Aim of the study: to develop a bilayered in vitro construct that simulates the tooth periodontium, for the purpose of tissue regeneration and investigation of physiologic and orthodontic loading. Methods: Two types of materials were used to develop this construct: Sol-Gel 60S10Mg scaffold (University of Erlangen) representing the hard tissue component of the and commercially available Geistlich Bio-Gide® collagen membrane representing the soft tissue component of the tooth attachment. Each scaffold was dynamically seeded with periodontal ligament cells. The seeded scaffolds were either cultured separately, or combined in a bilayered construct, for 2 weeks. Characterization of the individual scaffolds and the bilayered constructs included biological characterization: (cell viability, SEM imaging to confirm cell attachment and viability qRT-PCR expression for periodontium regeneration markers), and mechanical characterisation of scaffolds and constructs. Results: HPDLCs enjoyed a biocompatible 3D environment within the bi-layered construct components as demonstrated by live/dead images and LDH assay. Gene expression showed variation between individual scaffolds and constructs detached from the bilayer. Most genes showed a drop in expression in the construct except for markers of angiogenesis which showed their highest expression in Bio-Gide® detached constructs. Conclusion and clinical significance: the development of this model is important for physiologic simulation invitro and for tissue regeneration purposes of the tooth periodontium
The prognostic significance of minimal residual disease in adult Egyptian patients with precursor acute lymphoblastic leukemia
AbstractBackgroundMinimal residual disease (MRD) studies in adult acute lymphoblastic leukemia (ALL) give highly significant prognostic information superior to other standard criteria as age, gender and total leucocytic count (TLC) in distinguishing patients at high and low risk of relapse.ObjectivesWe aimed to determine the value of MRD monitoring by flowcytometry (FCM) in predicting outcome in adult Precursor ALL patients.Patients and methodsBone marrow (BM) samples were analyzed by 4-color FCM collected at diagnosis and after induction therapy (MRD1) to correlate MRD positivity with disease free survival (DFS) and overall survival (OS).ResultsStudy included 57 adult ALL patients (44 males and 13 females) with a median age of 22years (18–49). DFS showed no significant difference with age, gender and initial TLC (p=0.838, 0.888 and 0.743, respectively). Cumulative DFS at 2years was 34% for B-lineage ALL (n: 35) and 57% for T-lineage ALL (n: 18) (p=0.057). Cumulative DFS at 2years was 7% for MRD1 positive (high risk, HR) versus 57% for MRD1 negative patients (Low risk, LR) (p<0.001). Cumulative DFS at 2years was 29% for HR patients (n: 26) versus 55% for LR (n: 27) according to GMALL classification (p=0.064). Cumulative OS did not differ according to age, gender and TLC (p=0.526, 0.594 and 0.513, respectively). Cumulative OS at 2years was 36% for B ALL (n: 39) versus 77% for TALL (n: 18) (p=0.016) and was 49% for Philadelphia chromosome (Ph) negative patients versus 0% for Ph-positive patients (p<0.001). Regarding MRD1, OS at 2years was 18% for MRD1 HR (n: 17) versus 65% for MRD1 LR (n: 38) (p<0.001). OS was 35% for high-risk patients (n: 30) and 62% for low-risk patients (n: 27) classified according to GMALL risk stratification (p=0.017).ConclusionMRD by FCM is a strong independent predictor of outcome in terms of DFS and OS and is a powerful informative parameter in guiding individual treatment in ALL patients
Pharmacological Activities and Characterization of Phenolic and Flavonoid Compounds in Solenostemma argel Extract
Solenostemma argel is a desert medicinal plant indigenous to African countries. This research aims to study the pharmacological properties of Solenostemma argel plant. Aerial parts (leaves and flowers) of Solenostemma argel (Delile) Hayane were tested for antibacterial activity, antioxidant activity, anticancer, and anti-inflammatory activity. Phenolic and flavonoid contents of the plant were characterized. There was an increase in the antioxidant activity of Solenostemma argel extract from 12.16% to 94.37% by increasing concentration from10 µg/mL to 1280 µg/mL. The most sensitive organism was S. epidermidis with chloroform extract. The MTT assay revealed that methanolic extracts of Solenostemma argel showed potent cytotoxic effects on the A549, Caco-2, and MDAMB-231 cell lines, respectively. The anti-inflammatory activity increased by increasing the concentration of methanolic extract of Solenostemma argel, using indomethacin as a standard. Gallic acid was the most abundant phenolic acid, followed by synergic acid and p-coumaric acid, respectively. Catechin, quercetin, luteolin, kaempferol and rutin flavonoids were also found in the methanolic extract. GC-mass analysis showed that aerial parts of Solenostemma argel were rich in 2-(5-methyl-5 vinyl tetrahydro-2-furanyl)-2-propanol (11.63%), hexanoic acid methyl ester (10.93%), 3-dioxolane,4-methyl-2-pentadecyl (9.69%), phenol, 2-(1,1-dimethylethyl) (8.50%). It can be concluded that Solenostemma argel methanolic extract contain natural bioactive constituents with potential medicinal importance such as antioxidants, antimicrobial, anti-inflammatory, and anticancer activities
Gentamicin–Ascorbic Acid Encapsulated in Chitosan Nanoparticles Improved In Vitro Antimicrobial Activity and Minimized Cytotoxicity
Nano-drug delivery is a promising tactic to enhance the activity and minimize the cytotoxicity of antimicrobial drugs. In the current study, chitosan nanoparticles (CSNPs) were used as a carrier for the delivery of gentamicin sulfate (GM) and ascorbic acid (AA). The particles were synthesized by ionotropic gelation method and characterized by FT-IR, Zeta potential, and transmission electron microscope imaging. The obtained particles were evaluated for their in vitro antimicrobial activity and cytotoxicity. The prepared particles (GM–AA–CSNPs) under the optimal condition of 4:1:1 of chitosan to drug ratio showed encapsulation efficiency and loading capacities of 89% and 22%, respectively. Regarding biological activities, GM–AA–CSNPs showed a lower minimum inhibitory concentration (MIC) than free gentamicin sulfate and GMCSNPs mixture without presenting cytotoxicity against normal cells (HSF). Moreover, the GM–AA–CSNPs did not exhibit hemolytic activity. These results highlight that the GM–AA–CSNPs are confirmed as a hopeful formula for future investigations on the development of antimicrobial preparations
Risk Factors and Immune Response to Hepatitis E viral Infection among Acute Hepatitis Patients in Assiut, Egypt
Hepatitis E virus (HEV) infection is a common cause of acute viral hepatitis (AVH) in Egypt. We aimed to identify risk factors of HEV among acute hepatitis cases, measure HEV specific immune response to differentiate between symptomatic and asymptomatic infections. The study included symptomatic acute hepatitis (AH) patients (n=235) and asymptomatic contacts (n=200) to HEV cases. They completed a lifestyle questionnaire, screened for common hepatotropic viruses. Blood and serum samples were collected from patients and contacts after onset of disease and follow-up samples collected until convalescence. PBMC were separated and tested for specific HEV T-cell response by INFELISPOT assay. Serum samples were tested for IgM and IgG anti-hepatitis E virus by ELISA. IgM antibodies to HAV were detected in 19 patients (8.1%), 37 (15.7%) with HBV, 10 (4.3%) with HCV. HEV infection was identified in 42 (16%) patients with AVH. Of the 200 contacts, 14 (7%) had serological evidence of recent HEV asymptomatic infection, showed stronger CMI responses than HEV infected subjects (2540 ± 28 and 182 ± 389 ISCs /106 cells, respectively; P <0.05). In conclusion, HEV is a major cause of AVH in Egypt. Asymptomatic HEV patients are likely to have stronger immune responses including CMI responses, than symptomatic cases
Pharmacological Activities and Characterization of Phenolic and Flavonoid Compounds in Methanolic Extract of Euphorbia cuneata Vahl Aerial Parts
Euphorbia cuneata Vahl. (Euphorbiaceae) is a plant used in folk medicine for the treatment of pain and inflammation, although the biological basis for these effects has not been thoroughly investigated. The goal of this study was to investigate the pharmacological properties and characterization of phenolic and flavonoid compounds present in the aerial parts of E. cuneata. E. cuneata aerial parts were tested for antioxidant activity (DPPH), antibacterial activity, cell viability and cytotoxic effects, and anti-inflammatory activity. Phenolic and flavonoid contents (HPLC), and volatile constituents (GC-MS) were also characterized. The methanol extract had the highest antioxidant activity, while the ether extract had the lowest. The antioxidant activity of E. cuneata extract increased from (21.11%) at a concentration of 10 µg/mL to (95.53%) at a concentration of 1280 µg/mL. S. aureus was the most sensitive organism with the highest zone of inhibition and lowest MIC, with acetone extract; whereas C. tropicalis was the most resistant, with the lowest inhibition zone. MTT assay revealed that the methanol extract of E. cuneata had significant cytotoxic effects on the A549, Caco-2, and MDA-MB-231 cell lines, respectively. Lower concentrations of methanolic extract gave anti-inflammatory activity, and those effects were compared with indomethacin as a positive control. Pyrogallol was the most abundant phenolic acid, followed by caffeic, p-coumaric, ferulic, syringic, and gallic acids, respectively. The 7-hydroxyflavone and rutin flavonoids were also found in the extract. GC-mass analysis showed that aerial parts of E. cuneata were rich in methyl 12-hydroxy-9-octadecenoate. The volatile components were also composed of considerable amounts of hexadecanoic acid, methyl ester, (9E,12E)-octadeca-9,12-dienoyl chloride, and methyl octadeca-9,12-dienoate as well as a little amount of hexanal dimethyl acetal. It can be concluded that methanolic extract of E. cuneata could be used as an available source of natural bioactive constituents with consequent health benefits
Synthesis, biological evaluation and molecular modeling study of new (1,2,4-triazole or 1,3,4-thiadiazole)-methylthio-derivatives of quinazolin-4(3H)-one as DHFR inhibitors
A new series of 2-mercapto-quinazolin-4-one analogues was designed, synthesized and evaluated for their in vitro DHFR inhibition, antitumor and antimicrobial activity. Compound 17 proved to be the most active DHFR inhibitor with IC value of 0.01 lM, eight fold more active than methotrexate (MTX). Compounds 16 and 24 showed antitumor activity against human Caco2 colon and MCF-7 breast tumor cell lines with IC 50 50 values of 25.4 and 9.5 lg/ml, respectively. Compounds 15, 20, 21 and 30 showed considerable activity against the Gram-positive bacteria Staphylococcus aureus while 24 and 30 proved active against Bacillus subtilis with a magnitude of potency comparable to the broad spectrum antibiotic Ciprofloxacin. Strong activity was observed for 13, 14, 19, 20 and 24 against Candida albicans and Aspergillus flavus. Compound 17 shared a similar molecular docking mode with MTX and made a critical hydrogen bond and arene-arene interactions via Ala9 and Phe34 amino acid residues, respectively
Volume and shape changes of mandibular condyles in growing patients treated with fixed Class II appliances using CBCT
Objective: Evaluate the changes in the mandibular condyle volume and shape in growing Class II malocclusion patients, following the use of fixed functional Class II appliances (Forsus and Advacsync II). CBCT images were used to help understand which appliance might cause more changes. Methods: Twenty growing adolescent patients were randomly allocated to Two groups (Forsus and Advancesync II). A total of fourty CBCT images were taken pre- and posttreatment. The pre- and posttreatment CBCT images were segmented using a newly developed and validated semiautomatic condylar segmentation technique. and the quantitative assessment of the mean distance differences of the condyle surfaces was de using Iterative Closest Point technique. Results: A statistically significant increase in condylar volume was observed in both groups (Forsus and Advancesync II) and no significant differences in the magnitude of condylar volumes between both groups were found. There were no statistically significant changes in the mean distance differences of the condyles shape in both groups.Both groups (Forsus and Advancesync II) expressed different patterns of shape changes with no clear pattern associated with the treatment groups.