In vitro investigation of the apoptotic effect of heparin on lymphoblasts by using flow cytometric DNA analysis and fluorometric caspase-3 and -8 activities

The apoptotic effect of heparin on the lymphoblasts obtained from 12 newly diagnosed children with acute lymphoblastic leukemia (ALL) was investigated in vitro. The lymphoblasts were incubated with 0, 10, and 20 U/mL heparin concentrations at 0, 1, and 2 h. The percentages of the apoptotic lymphoblasts were calculated by flow cytometry (FCM), and activities of caspase-3 and -8 were simultaneously measured by fluorometric protease activity method. The apoptotic effect of heparin on the lymphoblasts was determined in 10 and 20 U/mL heparin concentrations (p < 0.005 and p < 0.001, respectively) while no apoptosis was detected in 0 U/mL heparin concentration at 0, 1, and 2 h. The apoptotic percentages of the lymphoblasts were higher at the first hour than those at 0 and 2 h in 10 and 20 U/mL heparin levels (p < 0.001). The highest apoptosis was found at first hour in 20 U/mL heparin concentration. Increased concentrations of heparin had an increasing effect on the percentages of the apoptotic lymphoblasts. Significantly higher caspase-3 and -8 activities were determined in 10 and 20 U/mL heparin concentrations than those in 0 U/mL heparin concentration at 0, 1, and 2 h (p < 0.001). There were no significant differences between the caspase-3 and -8 activities in 10 and 20 U/mL heparin concentrations at 1 and 2 h (p > 0.05), while statistically significant differences were simultaneously detected in the apoptotic rates of the lymphoblasts (p < 0.001). This may be due to that the study included the limited patients, or measurement of the caspase activities is a more sensitive method than the FCM analysis for determination of apoptosis because the activation time of the caspases takes a long time period. It was concluded that the apoptotic effect of heparin in vitro on lymphoblasts developed due to the extrinsic pathway of apoptosis via the caspase-3 and -8 activations in newly diagnosed ALL patients.     

A novel method for constructing an acellular 3D biomatrix from bovine spinal cord for neural tissue engineering applications

In this study, we aimed at generating 3-dimensional (3D) decellularized bovine spinal cord extracellular matrix-based scaffolds (3D-dCBS) for neural tissue engineering applications. Within this scope, bovine spinal cord tissue pieces were homogenized in 0.1 M NaOH and this viscous mixture was molded to attain 3D bioscaffolds. After resultant bioscaffolds were chemically crosslinked, the decellularization process was conducted with detergent, buffer, and enzyme solutions. Nuclear remnants in the native tissue and 3D-dCBS were determined with DNA content analysis and agarose gel electrophoresis. Afterward, 3D-dCBS were biochemically characterized in depth via glycosaminoglycan (GAG) content, hydroxyproline (HYP) assay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Cellular survival of human adipose-derived mesenchymal stem cells (hAMSCs) on the 3D-dCBS for 3rd, 7th, and 10th days was assessed via MTT assay. Scaffold and cell/scaffold constructs were also evaluated with scanning electron microscopy and histochemical studies. DNA contents for native and 3D-dCBS were respectively found to be 520.76 ± 18.11 and 28.80 ± 0.20 ng/mg dry weight (n = 3), indicating a successful decellularization process. GAG content, HYP assay, and SDS-PAGE results proved that the extracellular matrix was substantially preserved during the decellularization process. In conclusion, it is believed that the novel decellularization method may allow fabricating 3D bioscaffolds with desired geometry from soft nervous system tissues.     

Evaluating the Effect of Therapeutic Stem Cells on TRAIL Resistant and Sensitive Medulloblastomas

Mesenchymal stem cells (MSC) are emerging as novel cell-based delivery agents; however, a thorough investigation addressing their therapeutic potential in medulloblastomas (MB) has not been explored to date. In this study, we engineered human MSC to express a potent and secretable variant of a tumor specific agent, tumor necrosis factor-apoptosis-inducing ligand (S-TRAIL) and assessed the ability of MSC-S-TRAIL mediated MB killing alone or in combination with a small molecule inhibitor of histone-deacetylase, MS-275, in TRAIL-sensitive and -resistant MB in vitro and in vivo. We show that TRAIL sensitivity/resistance correlates with the expression of its cognate death receptor (DR)5 and MSC-S-TRAIL induces caspase-3 mediated apoptosis in TRAIL-sensitive MB lines. In TRAIL-resistant MB, we show upregulation of DR4/5 levels when pre-treated with MS-275 and a subsequent sensitization to MSC-S-TRAIL mediated apoptosis. Using intracranially implanted MB and MSC lines engineered with different combinations of fluorescent and bioluminescent proteins, we show that MSC-S-TRAIL has significant anti-tumor effects in mice bearing TRAIL-sensitive and MS-275 pre-treated TRAIL-resistant MBs. To our knowledge, this is the first study that explores the use of human MSC as MB-targeting therapeutic-vehicles in vivo in TRAIL-sensitive and resistant tumors, and has implications for developing effective therapies for patients with medulloblastomas.     

Detecting Surfactant-producing Microorganisms by the Drop-collapse Test

Summary A rapid method, ’drop-collapse’, was used for screening biosurfactant production by Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans and Phanerochaete chrysosporium liquid cultures. Before measuring the total biosurfactant, the drop-collapse method was used in order to detect rhamnolipid presence in the culture broths. The method was performed in a microwell plate; the polystyrene platform with small wells. If the culture broth contained biosurfactant, the droplets of the broth in the oil-coated wells collapsed. If not, there was no change in the shape of the droplets. Pseudomonas aeruginosa and Bacillus subtilis culture supernatants showed spreading movement, meaning that they produced biosurfactants. However, Candida albicans and Phanerochaete chrysosporium supernatants remained beaded, meaning they did not produce any type of microbial surfactant.     

Some benzoxazoles and benzimidazoles as DNA topoisomerase I and II inhibitors

Some novel fused heterocyclic compounds of 2, 5-disubstituted-benzoxazole and benzimidazole derivatives, which were previously synthesized by our group, were investigated for their inhibitory activity on both eukaryotic DNA topoisomerase I and II in a cell free system. 2-Phenoxymethylbenzimidazole (17), 5-amino-2-(p-fluorophenyl)benzoxazole (3), 5-amino-2-(p-bromophenyl)benzoxazole (5), 5-nitro-2-phenoxymethyl-benzimidazole (18), 2-(p-chlorobenzyl)benzoxazole (10) and 5-amino-2-phenylbenzoxazole (2) were found to be more potent as eukaryotic DNA topoisomerase I poisons than the reference drug camptothecin having IC(50) values of 14.1, 132.3, 134.1, 248, 443.5, and 495 microM, respectively. 5-Chloro-2-(p-methylphenyl)benzoxazole (4), 2-(p-nitrobenzyl)benzoxazole (6) and 5-nitro-2-(p-nitrobenzyl)benzoxazole (8) exhibited significant activity as eukaryotic DNA topoisomerase II inhibitors, having IC(50) values of 22.3, 17.4, 91.41 microM, respectively, showing higher potency than the reference drug etoposide.     

Elevated interleukin-12 and CXCL10 in subacute sclerosing panencephalitis

Immunosuppression associated with measles virus (MV) can be demonstrated by cytokine production failure in subacute sclerosing panencephalitis (SSPE) and may have implications on the pathogenesis of the disease. Cytokines (IL-12, IL-10, IL-4, IL-17, IL-18, IFN-alpha, IFN-gamma) and chemokines (CXCL8, CXCL10, CCL2 and CCL5) were measured in the cerebrospinal fluid (CSF) and serum samples from 60 patients with SSPE, 36 patients with infectious and/or inflammatory (IN) and 28 with other non-inflammatory (NIN) neurological diseases by ELISA. IL-12 p70+p40 was elevated in CSF and sera of SSPE when compared to the NIN group. However, the CSF levels of IL-12 p70 alone were not increased, indicating an increase of p40. The CSF of SSPE patients also showed relatively higher levels of IL-10 than that of the NIN group. CXCL10 levels in CSF were significantly higher in SSPE, whereas CXCL8 was increased in sera compared to NIN. No difference was detected in IFN-gamma, IFN-alpha, IL-17, IL-18, IL-4 or CCL2 and CCL5 levels. These results demonstrate that immune response against MV in SSPE may be impaired, although some T cell/Th1 inducing stimulations are present.     

Inhibition of alpha-glucosidase by aqueous extracts of some potent antidiabetic medicinal herbs

Diabetes mellitus is one of the most prevalant diseases of adults. Agents with alpha-glucosidase inhibitory activity have been useful as oral hypoglycemic drugs for the control of hyperglycemia in patients with type 2; noninsulin-dependent, diabetes mellitus (NIDDM). Investigation of some medicinal herbs: Urtica dioica, Taraxacum officinale, Viscum album, and Myrtus communis with alpha-glucosidase inhibitor activity was conducted to identify a prophylactic effect for diabetes in vitro. All plants showed differing potent alpha-glucosidase inhibitory activity. However, Myrtus communis strongly inhibited the enzyme (IC50 = 38 microg/mL). The inhibitory effect of these plants and some common antidiabetic drugs against the enzyme source (baker's yeast, rabbit liver, and small intestine) were also searched. Approximately all inhibitors used in this study showed quite different inhibitory activities, according to alpha-glucosidase origins. Furthermore, subsequent separation of the active material from Myrtus communis by HPLC showed that only one fraction acted as an a-glucosidase inhibitor.     

Fine needle aspiration cytology: a survey of current European practice

Fine needle aspiration cytology (FNAC) is practised widely throughout Europe. The majority of countries have dedicated cytopathologists as well as histopathologists practicing cytology. Despite this, FNAC is performed mostly by clinicians and radiologists except in the larger centres with dedicated staff with a special interest in cytopathology. The advent of One-Stop diagnostic services and image-guided procedures are prompting further development of FNAC clinics where cytopathologists take their own samples, issue reports in the same clinical session and take extra material for ancillary tests to complete the diagnosis. The volume of FNAC work varies accordingly; in dedicated centres FNAC represents up to 80% of the workload whilst, in the majority of countries, it represents one quarter or less. Hence, the rate of inadequate FNAC varies widely, depending on the local sampling policies and the organ, but does not exceed 25% in any of the countries. The most sampled organs are breast and thyroid, followed by lymph nodes. Most countries have dedicated training in cytopathology for pathology trainees, the duration varying between 6 months and 2 years of the total training time. This discussion, focusing on European practices, highlights the heterogeneity of FNAC activity but also its success in many centres where it is practiced to a high standard, particularly in breast, thyroid and lymph node pathology. The relatively high rate of inadequate material in some centres reflects local policies and calls for greater uniformity of FNAC practice, particularly specimen sampling. To achieve this, the future direction should concentrate on specialist training, to include performing as well as interpreting FNAC, as part of the curriculum. Current emphasis on web-based training may not provide first hand experience of the FNAC procedure and should be supplemented by attending FNAC clinics and developing the technique to its full potential.