Pollen morphology in Primula sect. Carolinella (Primulaceae) and its taxonomic implications

Pollen morphology in Primula section Carolinella has been investigated for the first time. Seven of the nine species constituting the section were available for study, i. e., P. cardioeides, P. chapaensis, P. intanoensis, P. kwangtungensis, P. kweichouensis, P. partschiana , and P. rugosa, A considerable variation in pollen morphology was found among the investigated species, particularly in number and arrangement of the apertures. Pollen of different species were either tricolpate, tricolporate, trisyncolpate, or polycolpate. Within Primula , the section Carolinella is diagnosed by having calyptrate capsules and leaves with revolute vernation, but the variation in pollen morphology indicates that this group is heterogeneous, and that either polycolpate pollen or a capsular lid has evolved more than once in the genus Primula.     

Fluorescence enhancement monitoring of pyrromethene laser dyes by metallic Ag nanoparticles

Fluorescence enhancement monitoring of pyrromethene laser dyes using their complexation with Ag nanoparticles (Ag NPs) was studied. The size of the prepared Ag NPs was determined by transmission electron spectroscopy and UV/Vis absorption spectroscopy. Mie theory was also used to confirm the size of NPs theoretically. The effect of different nanoparticle concentrations on the optical properties of 1 × 10^‐4 M PM dyes shows that 40%of Ag NPs concentration (40%C Ag NPs) in complex is the optimum concentration. Also, the effects of different concentrations of PM dyes in a complex was measured. Emission enhancement factors were calculated for all samples. Fluorescence enhancement efficiencies depended on the input pumping energy of a Nd‐YAG laser (wavelength 532 nm and 8 ns pulse duration) were reported and showed the lowest energy (28 and 32 mJ) in the case of PM567 and PM597, respectively. Copyright © 2014 John Wiley & Sons, Ltd.     

Scenedesmus obliquus: Antioxidant and antiviral activity of proteins hydrolyzed by three enzymes

Purpose

To obtain protein hydrolysates from fresh water green algae Scenedesmus obliquus by three different enzymes and evaluate its antioxidant and antiviral activity.

Surfactant Bilayers Maintain Transmembrane Protein Activity

In vitro studies of membrane proteins are of interest only if their structure and function are significantly preserved. One approach is to insert them into the lipid bilayers of highly viscous cubic phases rendering the insertion and manipulation of proteins difficult. Less viscous lipid sponge phases are sometimes used, but their relatively narrow domain of existence can be easily disrupted by protein insertion. We present here a sponge phase consisting of nonionic surfactant bilayers. Its extended domain of existence and its low viscosity allow easy insertion and manipulation of membrane proteins. We show for the first time, to our knowledge, that transmembrane proteins, such as bacteriorhodopsin, sarcoplasmic reticulum Ca²⁺ATPase (SERCA1a), and its associated enzymes, are fully active in a surfactant phase.     

Characterization of the mouseTcra-V22 gene subfamily

 T-cell receptors (Tcrs) of higher organisms play a key role in the specific recognition of self and non-self molecules in the immune system. The large number of Tcr variable (V) genes have been organized into V gene subfamilies according to their sequence similarity at the nucleotide and amino acid level. We cloned and characterized four new members of the Tcra-V22 gene subfamily at the genomic level using a simple and sensitive technique that can rapidly clone members of any multi-member gene family. Sequence analysis reveals that the four Tcra-V22 gene subfamily members have more than 98% sequence similarity in their coding regions, at the nucleotide and amino acid levels. However, the intron between the leader and the coding region varies up to 7% between members of the Tcra-V22 gene subfamily. Comparison of the multi-member Tcra-V22 gene subfamily with other multi-member Tcra-V gene subfamilies (V2, V8, and V11), shows that Tcra-V22 is unique in that it has multiple members with nearly identical amino acid sequence and which are not inherently pseudogenes. Sequence similarity analysis of the Tcra-V22 subfamily with the prototypes of all other Tcra-V subfamilies revealed that the Tcra-V22 subfamily has the closest sequence similarity to that of Tcra-V18 (77% at the nucleotide level and 71% at the amino acid level). Received: 22 March 1996 / Revised: 5 June 1996     

Atrial pacing, the forgotten pacing mode

In patients with sick sinus syndrome and normal atrioventricular conduction, physiological pacing can be accomplished with either a single chamber atrial pacemaker AAI/R or a dual chamber pacemaker DDD/R. The single chamber device has the advantages of simpler implantation and lower initial costs, while the dual chamber device offers protection in case atrioventricular conduction disturbances develop in the future. When rigorous attention is paid to the pre-implantation selection criteria, the incidence of reported second- or third-degree atrioventricular block varied between 0.4 and 1.8% per annum. Medical practice, however, has shifted to predominant implantation of DDD/R pacemakers in more than 95% of patients with sick sinus syndrome. Recent publications have reported an increase in left atrial diameter, decrease in left ventricular fractional shortening and increased incidence of atrial fibrillation in patients with DDD/R pacing as compared with patients with single chamber atrial devices. These changes were proportional to the percentage of ventricular paced beats. New algorithms in dual chamber devices have been developed in order to minimise ventricular stimulation. These are being evaluated at present. In my opinion there is still a place for atrial pacing in selected patients with sick sinus syndrome with a minimum risk of developing complete atrioventricular block. (Neth Heart J 2008;16(suppl 1): S25-S27.)     

Lansoprazole enhances the antidiabetic effect of dapagliflozin in fortified diet‐fed streptozotocin‐treated diabetic rats

Dapagliflozin (DAPA) is used for treating type 2 diabetes, whereas lansoprazole (LPZ) is used as a traditional antiulcer drug. The present study investigated the possible antidiabetic effects of LPZ on fortified diet‐fed streptozotocin (FDF/STZ)‐induced insulin‐resistant diabetic rats. On the basis of the current results, it can be concluded that LPZ could be used as an add‐on drug along with the conventional treatment for T2D as it showed beneficial effects in the current experimental model of insulin resistance.     

Comparison of Immune Restoration in Early versus Late Alpha Interferon Therapy against Hepatitis C Virus

Early alpha interferon (IFN-α) therapy against hepatitis C virus (HCV) rescues polyfunctional, virus-specific memory CD8⁺ T cells, but whether immune restoration is possible during late therapy remains controversial. We compared immune restoration of HCV-specific memory T cells in patients who cleared HCV infection spontaneously and following early or late IFN therapy. Multifunctional CD4⁺ and CD8⁺ memory T cells were detected in spontaneous resolvers and in individuals treated early following an acute infection. In contrast, limited responses were detected in patients treated during chronic infection, and the phenotype of HCV-specific cells was influenced by autologous viral sequences. Our data suggest that irreversible damage to the HCV-specific memory T-cell response is associated with chronic HCV infection.The majority of acute hepatitis C virus (HCV) infections become chronic, with persistent viremia and serious liver complications (12). Alpha interferon (IFN-α)-based therapy is the only approved treatment for chronic HCV; its success rate ranges from 40 to 90% depending on the infecting genotype (9, 18). The success of therapy is characterized by a sustained virological response (SVR), defined as undetectable HCV RNA in plasma at 6 months after termination of therapy. SVR rates are greatly enhanced if therapy is started between 3 and 6 months following acute HCV infection, but the underlying mechanisms are not well understood (27, 28). We have demonstrated that early interferon therapy for HCV can rescue and select for long-lived polyfunctional CD8⁺ memory T cells (1). Treatment-induced memory T cells were similar in phenotype and function to natural memory T cells generated following spontaneously resolved infection. They expressed high levels of CD127 and Bcl-2 (CD127^hi, Bcl-2^hi) and low levels of PD1 (PD1^lo) and were polyfunctional in nature (1). However, restoration of HCV-specific memory CD4⁺ T cells has not been examined. Furthermore, whether immune restoration is possible following the late initiation of therapy during the chronic phase remains controversial. Kamal et al. demonstrated that SVR is associated with a recovery in HCV-specific CD4⁺ T-cell responses (13). In contrast, Barnes et al. and Rahman et al. demonstrated that the induction of HCV-specific immunity during therapy does not correlate with outcomes (2, 21).