Optimization of carotenoid production by Umbelopsis ramanniana

Umbelopsis ramanniana was investigated to increase carotenoid production. Nine different carbon sources and six different nitrogen sources were evaluated for the maximum carotenoid production. The most effective nitrogen and carbon sources were KNO₃ and lactose, respectively. Then, the optimization of medium components for enhancement of carotenoid production by Umbelopsis ramanniana was achieved using Plackett–Burman design. Box–Behnken response surface methodology was applied to further optimize carotenoid and biomass production. Carbon to nitrogen ratio, lactose concentration, and shaking speed were studied as variables in Box–Behnken design. The optimum conditions for carotenoid and biomass production were determined as 32.42 g/L of lactose concentration, 20:1 of carbon to nitrogen ratio, and shaking speed of 130 rpm. The maximum carotenoid and biomass production under optimized conditions were 1141 μg/L (β-carotene-Eq) and 13.14 g/L, respectively. When compared to the control fermentation, carotenoid, and biomass production were increased by about 2 and 1.3 folds, respectively.     

Lung surfactant proteins in the early human placenta

Pulmonary surfactant is a complex mixture of phospholipids and four surfactant-associated proteins (SP-A, SP-B, SP-C and SP-D). The biological functions of SP-A and SP-D are primarily twofold, namely surfactant homeostasis and host defense. The hydrophobic surfactant proteins, SP-B and SP-C, are required for achieving the optimal surface tension reducing properties of surfactant by promoting the rapid adsorption of surfactant phospholipids along the alveolar surface. Despite the promising findings, only little is known about the extrapulmonary distribution of these proteins. Therefore, in this study, the presence of SP-A, SP-B, SP-C and SP-D in early human placenta has been investigated. First-trimester placental tissues (22–56 days) were obtained from women undergoing curettage during normal pregnancies. In parallel tissue sections, vimentin, cytokeratin-7 and CD-68 immunostainings were used for the identification of mesenchymal cells, trophoblast cells and Hofbauer cells, respectively. According to immunohistochemistry (IHC) results, SP-A, SP-B, SP-C and SP-D immunoreactivities with different staining intensities were observed in trophoblastic layers of chorionic villous tree, trophoblastic cell columns, stromal cells, Hofbauer cells, angiogenic cell cords and vascular endothelium. Fetal hematopoietic cells showed a variable staining pattern for all four surfactant proteins ranging from none to strong intensity. Western blotting of tissue extracts confirmed our IHC results. The presence of surfactant glycoproteins in early human placenta may yield a very important feature of surfactants during first trimester and enables further studies of the role of surfactants in various pregnancy complications.     

Learning the topological properties of brain tumors

This work presents a graph-based representation (a.k.a., cell-graph) of histopathological images for automated cancer diagnosis by probabilistically assigning a link between a pair of cells (or cell clusters). Since the node set of a cell-graph can include a cluster of cells as well as individual ones, it enables working with low-cost, low-magnification photomicrographs. The contributions of this work are twofold. First, it is shown that without establishing a pairwise spatial relation between the cells (i.e., the edges of a cell-graph), neither the spatial distribution of the cells nor the texture analysis of the images yields accurate results for tissue level diagnosis of brain cancer called malignant glioma. Second, this work defines a set of global metrics by processing the entire cell-graph to capture tissue level information coded into the histopathological images. In this work, the results are obtained on the photomicrographs of 646 archival brain biopsy samples of 60 different patients. It is shown that the global metrics of cell-graphs distinguish cancerous tissues from noncancerous ones with high accuracy (at least 99 percent accuracy for healthy tissues with lower cellular density level, and at least 92 percent accuracy for benign tissues with similar high cellular density level such as nonneoplastic reactive/inflammatory conditions).     

fruitless splicing specifies male courtship behavior in Drosophila

All animals exhibit innate behaviors that are specified during their development. Drosophila melanogaster males (but not females) perform an elaborate and innate courtship ritual directed toward females (but not males). Male courtship requires products of the fruitless (fru) gene, which is spliced differently in males and females. We have generated alleles of fru that are constitutively spliced in either the male or the female mode. We show that male splicing is essential for male courtship behavior and sexual orientation. More importantly, male splicing is also sufficient to generate male behavior in otherwise normal females. These females direct their courtship toward other females (or males engineered to produce female pheromones). The splicing of a single neuronal gene thus specifies essentially all aspects of a complex innate behavior.     

Development and brain delivery of chitosan-PEG nanoparticles functionalized with the monoclonal antibody OX26

The inhibition of the caspase-3 enzyme is reported to increase neuronal cell survival following cerebral ischemia. The peptide Z-DEVD-FMK is a specific caspase inhibitor, which significantly reduces vulnerability to the neuronal cell death. However, this molecule is unable to cross the blood-brain barrier (BBB) and to diffuse into the brain tissue. Thus, the development of an effective delivery system is needed to provide sufficient drug concentration into the brain to prevent cell death. Using the avidin (SA)-biotin (BIO) technology, we describe here the design of chitosan (CS) nanospheres conjugated with poly(ethylene glycol) (PEG) bearing the OX26 monoclonal antibody whose affinity for the transferrin receptor (TfR) may trigger receptor-mediated transport across the BBB. These functionalized CS-PEG-BIO-SA/OX26 nanoparticles (NPs) were characterized for their particle size, zeta potential, drug loading capacity, and release properties. Fluorescently labeled CS-PEG-BIO-SA/OX26 nanoparticles were administered systemically to mice in order to evaluate their efficacy for brain translocation. The results showed that an important amount of nanoparticles were located in the brain, outside of the intravascular compartment. These findings, which were also confirmed by electron microscopic examination of the brain tissue indicate that this novel targeted nanoparticulate drug delivery system was able to translocate into the brain tissue after iv administration. Consequently, these novel nanoparticles are promising carriers for the transport of the anticaspase peptide Z-DEVD-FMK into the brain.     

Repair of pharyngocutaneous fistulas with the submental artery island flap

Pharyngocutaneous fistulas after total laryngectomy are difficult to manage and are a cause for significant morbidity to the patient. When fistulas fail to close with conservative measures, debridement and flap closure are indicated. Although a number of techniques to repair pharyngocutaneous fistulas are described, each of these procedures has its drawbacks. The authors have used the submental island flap to close postoperative pharyngocutaneous fistulas in nine male patients during the past 4 years. The mean patient age was 65 years (range, 57 to 75 years). The submental island flap is based on the submental artery, a branch of the facial artery. The inner aspect of the fistula was initially formed using hinge flaps on the skin around the fistula. Once a watertight closure of inner side was created, the skin defect was closed with the submental island flap. The maximum flap size was 6 x 3 cm and the minimum size was 4 x 2 cm (average, 4.8 x 2.7 cm) in this series. Direct closure was achieved at all donor sites. Patients were followed for 6 months to 4 years. No major complication was noted in the postoperative period. All patients have successfully recovered their swallowing function. The submental island flap is safe, rapid, and simple to elevate and leaves minimal donor-site morbidity. The authors believe that this technique is a good alternative in the reconstruction of pharyngocutaneous fistulas. Application of the technique and results are discussed.     

Chemoenzymatic synthesis of (1S,2R)-1-amino-2-indanol, a key intermediate of HIV protease inhibitor, indinavir

The synthesis of (1S,2R)-1-amino-2-indanol, a key component of HIV protease inhibitor is accomplished in four steps starting from indanone efficiently and with high levels of diastereo- and enantioselectivity. The starting material is converted into 2-acetoxy-1-indanone involving Manganese (III) acetate oxidation . The 2-acetoxyketone is hydrolyzed to 2-hydroxy-1-indanone enantioselectively using Rhizopus oryzae. Selective reduction of 2-hydroxyoxime derivative, derived from the 2-hydroxyketone, gives the amino alcohol up to 98% diastereo- and enantioselectivity.