<Emphasis Type=Italic>Aphelenchus avenae</Emphasis> (Nematoda: Aphelenchidae) under the rhizosphere of <Emphasis Type=Italic>Brassica napus</Emphasis>

Soil samples under the rhizosphere of Brasicca napus were collected from three localities (Bílé Podolí, Prague, Kylešovice). All three localities were positive for the presence of Aphelenchus avenae. Morphological and molecular features of A. avenae are presented in this research note.     

Outer membrane protein A (OmpA) from Shigella flexneri 2a: A promising subunit vaccine candidate

Shigellosis is the leading cause of childhood mortality and morbidity. Despite many years of extensive research a practical vaccine is not yet available against the disease. Recent studies illustrate that bacterial outer membrane proteins are budding target as vaccine antigen. Outer membrane proteins A (OmpA) are among the most immunodominant antigens in the outer membrane of gram negative bacteria and possess many characteristics desired of a vaccine candidate. We observe that OmpA of Shigella flexneri 2a is crossreactive and common antigen among Shigella spp. and the epitope is widely exposed on the cell surface as well as capable of evoking protective immunity in mice. The protective immunity involves participation of both the humoral and cellular immune responses, since OmpA boosts rapid induction of IgG and IgA in both the systemic and mucosal compartments and also activates Th1 cells. The immunopotentiating activity of OmpA is mediated by its ability to bind and stimulate macrophages and up-regulate the surface expression of MHCII, CD80 and CD40, leading to activation of CD4⁺ T cells to secrete cytokines and express chemokine receptor and IL-12Rβ2, thereby orchestrating the bridge between innate and adaptive immune responses. This ability is dependent on Toll-like receptor 2 (TLR2), as demonstrated by lack of response by TLR2 knockdown macrophages to OmpA. Hence this property of OmpA to link innate and adaptive immunity via TLR2 offers a novel vista to develop vaccine against shigellosis.     

Determination of Genetic Diversity of the Morinda tinctoria Population in Historical Mandore Garden

Morinda tinctoria (Rubiaceae) commonly called as ‘Indian Mulberry’ is one of the avenue trees of historically important Mandore garden planted anthropogenically in the past. Objective of this study was to determine the genetic diversity of M. tinctoria population at Mandore garden using Random Amplified Polymorphic DNA and Inter Simple Sequence Repeat Markers. A total of 97 bands were produced from 10 random amplified polymorphic DNA primers (49 bands) and 8 inter simple sequence repeat primers (48 bands). No polymorphic bands were obtained in any accessions using the two methods, which strongly suggested that M. tinctoria of this region appear as identical clones. Monomorphic pattern revealed the clonal plantation of M. tinctoria in this historical garden. This is the first report on use of molecular markers to infer the ancient plantation history. Consequences of genetically monomorphic population under global climate changes are discussed and conservation strategy is proposed.     

Functionally aberrant dendritic cell subsets and expression of DC-SIGN differentiate acute from chronic HBV infection

Background

Dendritic cells (DCs) promote pathogen recognition, uptake and presentation of antigen through DC-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and toll-like receptors (TLRs).

Aims and Objectives

We aimed to study temporal changes in DCs, TLRs and DC-SIGN during acute viral hepatitis B (AVHB) infection and compare them to chronic (CHB) and to investigate the earliest time point of activated pathogen recognition receptors in hepatitis B viral infection.

Methods

We measured the frequencies of circulating myeloid (mDC) and plasmacytoid (pDC) dendritic cells and IFN-α production along with the expression of DC-SIGN and Toll Like Receptors (TLR's) in HBV patients at different time points. Also investigated in healthy volunteers, the dynamic changes in TLRs expression after receiving hepatitis B vaccine.

Results

On follow-up of AVHB patients, we found the mDC population was significantly higher at week 4 and 6 (p < 0.02, 0.01), whereas the pDC population was unchanged at week 6 compared with week 0. Whereas frequencies of mDCs and pDCs were found to be elevated in AVHB and CHB patients than HC (p < 0.00 and 0.01, respectively) but was comparable among AVHB vs CHB. The DCs in CHB patients were functionally impaired with significantly low IFN-α production and low DCSIGN expression (p < 0.04 and 0.00, respectively). Even after stimulation by TLR agonists, no change was found in IFN-α production in CHB patients. MyD88 and IL-6, IFN-α mRNA levels were also found down-regulated. Interestingly, on follow-up after HBV vaccine, TLRs expression was found high at day 3 after vaccination.

Discussion

The initial events of immune activation might be responsible for modulating immune response. These novel observations would pave the way for the development of antiviral strategies for chronic HBV infection.

     

Minireview: mechanisms by which the metabolic syndrome and diabetes impair memory

Type 2 diabetes is associated with an increased risk of cognitive dysfunction. These effects seem particularly true for memory functions. This article examines how diabetes and the biological changes that occur with diabetes such as hyperglycemia, changes in insulin concentration, hypertension, and changes in lipid levels might lead to these alterations in cognitive functioning, with an emphasis on the mechanisms leading to changes in memory.     

Effects of sustained-release bupropion among persons interested in reducing but not quitting smoking

PURPOSE: To determine whether sustained-release bupropion promotes smoking reduction leading to smoking cessation among persons who wish to reduce their amount of smoking, but who are unwilling to quit or who perceive themselves as being unable to quit. METHODS: Current smokers were assigned randomly to receive either sustained-release bupropion (150 mg twice daily) or matching placebo. During an initial 6-month smoking reduction phase, those who were willing to quit entered a 7-week cessation phase, during which study medication was continued. RESULTS: Four-week continuous abstinence rates were 14% (41/295) in the bupropion group and 8% (25/299) in the placebo group (P = 0.02) during treatment. However, this benefit did not continue after treatment was stopped; subsequent continuous abstinence rates were 7% (20/295) in the bupropion group and 5% (16/299) in the placebo group (P = 0.50). Similar proportions of subjects entered the cessation phase in both treatment groups (38% [n = 113] of those in the bupropion group and 34% [n = 101] of those in the placebo group), although the time until a cessation attempt was shorter for those taking bupropion (median, 64 days vs. 118 days, P = 0.008). The extent of smoking reduction (measured by urinary cotinine concentrations) among the 327 subjects who did not enter the cessation phase was significantly greater (P <0.05) in those treated with bupropion during the reduction treatment phase, but not during the month 12 follow-up visit (P = 0.25). CONCLUSION: Sustained-release bupropion, when used in smokers initially not willing to make a cessation attempt, can help sustain smoking reduction while subjects are on active medication, reduce the time until the next cessation attempt, and increase short-term abstinence rates. However, these benefits were modest and not sustained after bupropion was discontinued.