The alteration of PLCζ protein expression in unexplained infertile and asthenoteratozoospermic patients: A potential effect on sperm fertilization ability

Failed oocyte activation has been observed in unexplained infertile (UI) and asthenoteratozoospermic (AT) men. The deficiency of phospholipase C‐zeta (PLCζ) could be a possible reason for such failures and has not been studied yet. We investigated the expression and localization of PLCζ protein in the sperms of patients with UI and AT conditions. The relationships between PLCζ‐related parameters with male age, sperm characteristics, DNA integrity, and cellular maturity were assessed. Semen samples were collected from fertile (n = 40), UI (n = 40), and AT (n = 40) men. Subsequently, semen analysis, DNA fragmentation, hyaluronic acid‐binding ability, and PLCζ level along with its distribution were evaluated using computer‐assisted sperm analyzer, sperm chromatin structure assay (SCSA), hyaluronic acid‐binding assay (HBA), western blot analysis and immunofluorescence microscopy, respectively. Unlike SCSA, the values of HBA, and PLCζ expression were significantly reduced in UI and AT patients compared to fertile men, whereas no significant differences were observed among the experimental groups in terms of PLCζ localization patterns. The regression analysis also showed that HBA is the only variable associated with PLCζ levels. Furthermore, the correlation of male age with PLCζ localization in postacrosomal, equatorial, and acrosomal+postacrosomal+equatorial (A+PA+E) patterns, as well as the relation of normal morphology, with the (A+PA+E) pattern, remained in the regression model. Our findings indicated that reduced PLCζ level along with the increased DNA fragmentation and impaired maturation may be possible etiologies of decreased fertilization in the studied subjects.     

Novel Delivery Systems for Interferons

ABSTRACT

Interferons, IFNs, are among the most widely studied and clinically used biopharmaceuticals. Despite their invaluable therapeutic roles, the widespread use of IFNs suffers from some inherent limitations, mainly their relatively short circulation lifespan and their unwanted effects on some non-target tissues. Therefore, both these constraints have become the central focus points for the research efforts on the development of a variety of novel delivery systems for these therapeutic agents with the ultimate goal of improving their therapeutic end-points. Generally, the delivery systems currently under investigation for IFNs can be classified as particulate delivery systems, including micro- and nano-particles, liposomes, minipellets, cellular carriers, and non-particulate delivery systems, including PEGylated IFNs, other chemically conjugated IFNs, immunoconjugated IFNs, and genetically conjugated IFNs. All these strategies and techniques have their own possibilities and limitations, which should be taken into account when considering their clinical application. In this article, currently studied delivery systems/techniques for IFN delivery have been reviewed extensively, with the main focus on the pharmacokinetic consequences of each procedure.     

Direct chemiluminescence determination of penicillin G potassium and a chemometrical optimization approach

A highly selective and simple chemiluminescence (CL) method for determination of penicillin G potassium (PGK) was developed. In the proposed method, CL was elicited from PGK upon its oxidation with H₂O₂. The light emission was enhanced in the presence of N‐cetyl‐N,N,N‐trimethylammonium bromide (CTMAB). An experimental design, central composite design (CCD), was used to realize the optimized variables, including pH, surfactant (CTMAB) and H₂O₂ concentrations. Under optimum condition, the calibration graph was linear in the range 3.3 × 10^?3–3.3 × 10^?1 mmol/L, with a detection limit of 8.8 × 10^?4 mmol/L for PGK. The precision was calculated by analysing samples containing 1.6 × 10^?1 mmol/L PGK (n = 5) and the relative standard deviation (RSD) was 1.40%. The utility of this method was demonstrated by determining PGK in pharmaceutical formulations for injection. The proposed method was validated by a reference method. Copyright © 2011 John Wiley & Sons, Ltd.     

Dynamics of adaptation of stomatal behaviour to moderate or high relative air humidity in Tradescantia virginiana

Chlorophyll fluorescence imaging was used to measure stomatalclosure in response to desiccation of Tradescantia virginianaleaves grown under high (90%) and moderate (55%) relative humidities(RHs), or transferred between these humidities. Stomata in leavesgrown at high RH were less responsive to desiccation than thoseof leaves grown at moderate RH. Stomata of plants transferredfrom moderate RH conditions to high RH showed the same diminishedclosure in response to desiccation as did stomata that developedat high RH. This response was found both when the leaves werefully expanded and when still actively expanding during themoderate RH pre-treatment. Four days of exposure to high RHwas the minimal exposure time to induce the diminished closureresponse. When leaves were grown in high RH prior to a 10 dmoderate RH treatment, the reduced stomatal closure responseto desiccation was only reversed in leaves (regions) which wereactively expanding during moderate RH treatment. This indicatesthat with respect to stomatal responses to desiccation, highRH leaf regions have a limited capacity to adapt to moderateRH conditions. The decrease in responsiveness to desiccationof the stomata, induced by long-term exposure to high RH, wasnot due to osmotic adjustment in the leaves. Within 1 d aftertransferring moderate RH-grown plants to a high RH, the abscisicacid (ABA) concentration of their leaves decreased to the lowlevel of ABA found in high RH-grown leaves. The closure responsein leaves exposed to high RH for 5 d, however, could not befully restored by the application of ABA. Transferring plantsfrom high to moderate RH resulted in increased ABA levels within2 d without a recovery of the stomatal closing response. Itis discussed that the diminished stomatal closure in plantsexposed to high RH could be due to changes in the signallingpathway for ABA-related closure of stomata or to an increasedsequestration of ABA by mesophyll tissue or the symplast inthe epidermis, induced by a longer period (several days) ofa low ABA level. Key words: Abscisic acid, desiccation, PSII efficiency, relative water content, stomatal closure, vapour pressure deficit, water potential Received 8 October 2007; Revised 5 November 2007 Accepted 9 November 2007     

Guaianolide from Jurinea carduiformis

8-Desacylrepin, a new guaianolide, has been isolated from Jurinea carduiformis.     

Human embryonic stem cell-derived neural precursor transplants in collagen scaffolds promote recovery in injured rat spinal cord

Background aimsSeveral studies have reported functional improvement after transplantation of in vivo-derived neural progenitor cells (NPC) into injured spinal cord. However, the potential of human embryonic stem cell-derived NPC (hESC-NPC) as a tool for cell replacement of spinal cord injury (SCI) should be considered.MethodsWe report on the generation of NPC as neural-like tubes in adherent and feeder-free hESC using a defined media supplemented with growth factors, and their transplantation in collagen scaffolds in adult rats subjected to midline lateral hemisection SCI.ResultshESC-NPC were highly expressed molecular features of NPC such as Nestin, Sox1 and Pax6. Furthermore, these cells exhibited the multipotential characteristic of differentiating into neurons and glials in vitro. Implantation of xenografted hESC-NPC into the spinal cord with collagen scaffold improved the recovery of hindlimb locomotor function and sensory responses in an adult rat model of SCI. Analysis of transplanted cells showed migration toward the spinal cord and both neural and glial differentiation in vivo.ConclusionsThese findings show that transplantation of hESC-NPC in collagen scaffolds into an injured spinal cord may provide a new approach to SCI.     

Two new germacranolides from Onopordon leptolepis

The investigation of the aerial parts of O. leptolepis afforded, in addition to a known polyynaldehyde and onopordopicrin, two further germacranolides. The structures are elucidated by spectroscopic methods and by conversion to the corresponding acetates.