Morphological and Molecular Variation of Morus laevigata in India

Morus spp., commonly known as mulberry, is significantly associated with human civilization and spread of silk-culture from Asia to Europe, Africa and Latin America. One of its species, Morus laevigata, traditionally well known for its timber value, forage use and silkworm's feed, is widely distributed in India extending from Himalayan foothill to Andaman islands. The variability occurring for 12 morpho-biochemical parameters and RAPD profiles, generated with 13 selected RAPD primers, for M. laevigata accessions from six different zones were investigated. Analyses revealed high degree of genotypic similarity of collection from Himalayan foothill (West Bengal) with those from Andaman Islands. Specific accessions from central India and south India also revealed genotypic similarities with specific accessions from north-east India. These observations are discussed in the context of clonal propagation of mulberry and evolutionary perspective of dispersal of this species, through human activities     

Cytologic diagnosis of small cell anaplastic hepatoblastoma: a case report

BACKGROUND: Small cell anaplastic hepatoblastoma (HB) is the least common subtype of HB. There are few articles in the literature describing the cytologic characteristics of this rare subtype. CASE: A 5-year-old girl present with a progressively enlarging abdominal mass. Ultrasound examination revealed the mass to be arising within the right lobe of the liver. Fine needle aspiration (FNA) of the mass revealed primitive cells with a high nuclear/cytoplasmic ratio and hyperchromatic, ovoid nuclei in poorly cohesive clusters as well as dispersed singly. These cells closely resembled those of small round cell tumors of childhood. CONCLUSION: The cytologic differential diagnosis of undifferentiated HB must include small round cell tumors of childhood. With knowledge of the typical cytomorphologic appearance of HB in association with clinical and radiologic information, one can offer a reliable preoperative diagnosis on FNA.     

Altered arachidonic acid metabolism impairs functional vasodilation in metabolic syndrome

These studies tested the hypothesis that in obese Zucker rats (OZRs), a model of metabolic syndrome, the impaired functional vasodilation is due to increased thromboxane receptor (TP)-mediated vasoconstriction and/or decreased prostacyclin-induced vasodilation. Spinotrapezius arcade arterioles from 12-wk-old lean (LZR) and OZR were chosen for microcirculatory observation. Arteriolar diameter (5 LZR and 6 OZR) was measured after 2 min of muscle stimulation in the absence or presence of 1 microM SQ-29548 (TP antagonist). Additionally, arteriolar diameter (6 for each group) was measured after application of iloprost (prostacyclin analog; 0.28, 2.8, and 28 microM), arachidonic acid (10 microM), and sodium nitroprusside (0.1, 1, and 10 microM) in the absence or presence of 1 microM SQ-29548. A 10 microM concentration of adenosine was used to induce a maximal dilation. Basal diameters were not different between LZRs and OZRs. Functional hyperemia and arachidonic acid-mediated vasodilations were significantly attenuated in OZR compared with LZR, and treatment with 1 microM SQ-29548 significantly enhanced the dilations in OZRs, although it had no effect in LZRs. Vasodilatory responses to iloprost and sodium nitroprusside (1 and 10 microM) were significantly reduced in OZR. Adenosine-mediated vasodilation was not different between groups. These results suggest that the impaired functional dilation in the OZR is due to an increased TP-mediated vasoconstriction and a decreased PGI2-induced vasodilation.     

Microscopic investigation of erythrocyte deformation dynamics

The understanding of erythrocyte deformation under conditions of high shear stress and short exposure time is central to the study of hemorheology and hemolysis within prosthetic blood contacting devices. A combined computational and experimental microscopic study was conducted to investigate the erythrocyte deformation and its relation to transient stress fields. A microfluidic channel system with small channels fabricated using polydimethylsiloxane on the order of 100 mum was designed to generate transient stress fields through which the erythrocytes were forced to flow. The shear stress fields were analyzed by three-dimensional computational fluid dynamics. Microscopic images of deforming erythrocytes were experimentally recorded to obtain the changes in cell morphology over a wide range of fluid dynamic stresses. The erythrocyte elongation index (EI) increased from 0 to 0.54 with increasing shear stress up to 123 Pa. In this shear stress range, erythrocytes behaved like fluid droplets, and deformed and flowed following the surrounding fluid. Cells exposed to shear stress beyond 123 Pa (up to 5170 Pa) did not exhibit additional elongation beyond EI=0.54. Two-stage deformation of erythrocytes in response to shear stress was observed: an initial linear elongation with increasing shear stress and a plateau beyond a critical shear stress.     

Jasmonic acid induced changes in protein pattern, antioxidative enzyme activities and peroxidase isozymes in peanut seedlings

Protein pattern, ammonia content, glutamine synthetase activity, lipid peroxidation, superoxide dismutase, catalase, peroxidase and peroxidase isoforms were studied in the leaves and roots of 7-d-old peanut (Arachis hypogaea L. cv. JL-24) seedlings treated by 25, 100 and 250 μM jasmonic acid (JA). SDS-PAGE protein profile of leaves and roots after JA application showed a significant increase in 18, 21, 30, 45, 47 and 97.4 kDa proteins and significant decrease in 22 and 36 kDa proteins. Pathogenesis related PR-18 was specific in leaves at 250 μM JA and PR-21 have cross reacted differently with 21 and 30 kDa proteins in leaves and roots treated by all JA concentrations. Further, the immunoblot analysis with glutamine synthetase, GS-45 antibodies revealed a specific cross reaction with 45 and 47 kDa proteins of both control and JA treated leaves, however, higher at 100 and 250 μM JA treated leaves than control ones. Further, the malondialdehyde (MDA) content significantly increased in leaves and roots treated with JA, indicated membrane damage with JA treatments that led to the generation of peroxidation products. The peroxidase isozymic pattern showed two specific isoforms. Besides, the activities of SOD and catalase were significantly elevated in JA treated leaves.     

CASK interacts with PMCA4b and JAM-A on the mouse sperm flagellum to regulate Ca2+ homeostasis and motility

Deletion of the highly conserved gene for the major Ca²⁺ efflux pump, Plasma membrane calcium/calmodulin‐dependent ATPase 4b (Pmca4b), in the mouse leads to loss of progressive and hyperactivated sperm motility and infertility. Here we first demonstrate that compared to wild‐type (WT), Junctional adhesion molecule‐A (Jam‐A) null sperm, previously shown to have motility defects and an abnormal mitochondrial phenotype reminiscent of that seen in Pmca4b nulls, exhibit reduced (P < 0.001) ATP levels, significantly (P < 0.001) greater cytosolic Ca²⁺ concentration ([Ca²⁺]_c) and ～10‐fold higher mitochondrial sequestration, indicating Ca²⁺ overload. Investigating the mechanism involved, we used co‐immunoprecipitation studies to show that CASK (Ca²⁺/calmodulin‐dependent serine kinase), identified for the first time on the sperm flagellum where it co‐localizes with both PMCA4b and JAM‐A on the proximal principal piece, acts as a common interacting partner of both. Importantly, CASK binds alternatively and non‐synergistically with each of these molecules via its single PDZ (PDS‐95/Dlg/ZO‐1) domain to either inhibit or promote efflux. In the absence of CASK–JAM‐A interaction in Jam‐A null sperm, CASK–PMCA4b interaction is increased, resulting in inhibition of PMCA4b's enzymatic activity, consequent Ca²⁺ accumulation, and a ～6‐fold over‐expression of constitutively ATP‐utilizing CASK, compared to WT. Thus, CASK negatively regulates PMCA4b by directly binding to it and JAM‐A positively regulates it indirectly through CASK. The decreased motility is likely due to the collateral net deficit in ATP observed in nulls. Our data indicate that Ca²⁺ homeostasis in sperm is maintained by the relative ratios of CASK–PMCA4b and CASK–JAM‐A interactions. J. Cell. Physiol. 227: 3138–3150, 2012. © 2011 Wiley Periodicals, Inc.     

Review physical and chemical aspects of stabilization of compounds in silk

The challenge of stabilization of small molecules and proteins has received considerable interest. The biological activity of small molecules can be lost as a consequence of chemical modifications, while protein activity may be lost due to chemical or structural degradation, such as a change in macromolecular conformation or aggregation. In these cases, stabilization is required to preserve therapeutic and bioactivity efficacy and safety. In addition to use in therapeutic applications, strategies to stabilize small molecules and proteins also have applications in industrial processes, diagnostics, and consumer products like food and cosmetics. Traditionally, therapeutic drug formulation efforts have focused on maintaining stability during product preparation and storage. However, with growing interest in the fields of encapsulation, tissue engineering, and controlled release drug delivery systems, new stabilization challenges are being addressed; the compounds or protein of interest must be stabilized during: (1) fabrication of the protein or small molecule-loaded carrier, (2) device storage, and (3) for the duration of intended release needs in vitro or in vivo. We review common mechanisms of compound degradation for small molecules and proteins during biomaterial preparation (including tissue engineering scaffolds and drug delivery systems), storage, and in vivo implantation. We also review the physical and chemical aspects of polymer-based stabilization approaches, with a particular focus on the stabilizing properties of silk fibroin biomaterials.     

Transcriptional Co-activator p300 Maintains Basal Hepatic Gluconeogenesis

A major cause of fasting hyperglycemia in diabetes mellitus is unregulated hepatic glucose production (HGP). Insulin suppresses HGP by phosphorylating CBP and disassembling the CREB-CBP complex from gluconeogenic genes. p300 is closely related to CBP; but in contrast to CBP, p300 binds constitutively to CREB due to the absence of phosphorylation site found in CBP. In a phosphorylation-competent p300(G442S) knock-in mouse model, we demonstrate that HGP is now exquisitely sensitive to insulin suppression. p300(G422S) and hepatic-deleted p300 mice exhibited significant lower blood glucose levels in the fasted and post-prandial states, indicating a role for p300 in maintaining basal HGP.