Both the hippocampus and striatum are involved in consolidation of motor sequence memory

Functional magnetic resonance imaging (fMRI) was used to investigate the cerebral correlates of motor sequence memory consolidation. Participants were scanned while training on an implicit oculomotor sequence learning task and during a single testing session taking place 30 min, 5 hr, or 24 hr later. During training, responses observed in hippocampus and striatum were linearly related to the gain in performance observed overnight, but not over the day. Responses in both structures were significantly larger at 24 hr than at 30 min or 5 hr. Additionally, the competitive interaction observed between these structures during training became cooperative overnight. These results stress the importance of both hippocampus and striatum in procedural memory consolidation. Responses in these areas during training seem to condition the overnight memory processing that is associated with a change in their functional interactions. These results show that both structures interact during motor sequence consolidation to optimize subsequent behavior.     

Synthesis of N-tetra-O-acetyl-β-d-glucopyranosyl-N′-(4′,6′-diarylpyrimidin-2′-yl)thioureas

Some 2-amino-4,6-diarylpyrimidines 2 have been prepared from substituted benzylideneacetophenones and guanidine hydrochloride in the presence of alkali by conventional heating in alcoholic medium and microwave heating in solvent-free conditions. N-(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)-N′-(4′,6′-diarylpyrimidin-2′-yl)thioureas 4 have been synthesized by reaction of per-O-acetylated glucopyranosyl isothiocyanate 1 and substituted 2-amino-4,6-diarylpyrimidines 2. Two different methods have been used, namely, refluxing in anhydrous dioxane and solvent-free microwave-assisted coupling. The second procedure afforded higher yields in much shorter reaction times. The compounds 2 and 4 were tested for their antibacterial and antifungal activities in vitro against Staphylococcus epidermidis, Enterobacter aerogenes and Candida albicans by disc diffusion method.     

Effect of benzothiadiazole on the metabolome of Arabidopsis thaliana

Benzothiadiazole (BTH) is a functional analog of the plant endogenous hormone-like compound, salicylic acid (SA), which is required for the induction of plant defense genes leading to systemic acquired resistance (SAR). Previous molecular and genetic studies have suggested that BTH itself might potentiate SAR resulting in the induction of several pathogenesis-related (PR) genes. However, the changes in the metabolome, which occur as a result of BTH-treatment, remain unclear. In this study, metabolic alterations in BTH-treated Arabidopsis thaliana were investigated using nuclear magnetic resonance (NMR) spectroscopy followed by multivariate data analyses such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Both PCA and PLS-DA show that increase of glucose, glutamine, inositol, malic acid, sucrose, and threonine as well as BTH and its degraded metabolites contribute to the clear discrimination of the metabolome of BTH-treated Arabidopsis from control plants. However, the levels of phenolic metabolites, which have generally been observed to be induced by other signaling molecules were significantly reduced in BTH-treated Arabidopsis. In addition to these changes due to BTH-treatment, it was also found that the EtOH used as a solvent in this treatment may per se act as an inducer of the accumulation of a flavonoid.     

Genetic Diversity of <Emphasis Type="Italic">Hevea</Emphasis> IRRDB’81 Collection Assessed by RAPD Markers

The majority of Hevea (Hevea brasiliensis Muell. Arg.) genetic resource in Vietnam derived from the IRRDB’81 germplasm collected in the Amazonian habitats of the genus. Random amplified polymorphic DNA (RAPD) analysis was used to examine the genetic diversity and structure of the IRRDB’81 germplasm. A total of 59 accessions from 13 different districts of the Brazilian states namely Acre, Rondonia, and Mato Grosso were brought into the study using six arbitrarily preselected primers. Sixty-five RAPD band patterns ranging in size from 0.2 to 3.0 kbp were scored for analysis. Differences in the level of DNA polymorphism among the districts and states were revealed. The percentage of the polymorphic DNA fragments calculated for 13 individual districts varied from 15.38 to 70.77%. The mean values of heterozygosity within the district varied from 0.064 to 0.264. Pairwise district Nei’s genetic distance values ranged from 0.046 for Catriquacu and Itanba of Mato Grosso to 0.304 for Tarauaca of Acre and Aracatuba of Mato Grosso. The estimated values of Shannon’s diversity index ranged from 0.093 for the Assis-Brasil district of Acre to 0.389 for the Jiparana district of Rondonia. The analysis of molecular variance (AMOVA) indicated that most of the genetic variations were found among accessions within the districts, while interdistrict variance component accounted for 14.1% only. The low interdistrict differentiation probably implied an extensive gene flow among them. Both the principal coordinate analysis and UPGMA cluster analysis based on genetic distance values revealed a varying degree of separation among the districts and that conformed to geographical origins of Hevea IRRDB’81 collection.     

Prevalence of Antibodies against Avian Influenza A (H5N1) Virus among Cullers and Poultry Workers in Ho Chi Minh City, 2005

Background

Between 2003 and 2005, highly pathogenic avian influenza A (H5N1) viruses caused large scale outbreaks in poultry in the Ho Chi Minh City area in Vietnam. We studied the prevalence of antibodies against H5N1 in poultry workers and cullers who were active in the program in Ho Chi Minh City in 2004 and 2005.

Methodology/Principal Findings

Single sera from 500 poultry workers and poultry cullers exposed to infected birds were tested for antibodies to avian influenza H5N1, using microneutralization assays and hemagglutination inhibition assay with horse blood. All sera tested negative using microneutralization tests. Three samples showed a 1∶80 titer in the hemagglutination inhibition assay.

Conclusions/Significance

This study provides additional support for the low transmissibility of clade 1 H5N1 to humans, but limited transmission to highly exposed persons cannot be excluded given the presence of low antibody titers in some individuals.     

Distinct Differences in the Expansion and Phenotype of TB10.4 Specific CD8 and CD4 T Cells after Infection with Mycobacterium tuberculosis

Background

Recently we and others have identified CD8 and CD4 T cell epitopes within the highly expressed M. tuberculosis protein TB10.4. This has enabled, for the first time, a comparative study of the dynamics and function of CD4 and CD8 T cells specific for epitopes within the same protein in various stages of TB infection.

Methods and Findings

We focused on T cells directed to two epitopes in TB10.4; the MHC class I restricted epitope TB10.4 _3–11 (CD8/10.4 T cells) and the MHC class II restricted epitope TB10.4 _74–88 (CD4/10.4 T cells). CD4/10.4 and CD8/10.4 T cells displayed marked differences in terms of expansion and contraction in a mouse TB model. CD4/10.4 T cells dominated in the early phase of infection whereas CD8/10.4 T cells were expanded after week 16 and reached 5–8 fold higher numbers in the late phase of infection. In the early phase of infection both CD4/10.4 and CD8/10.4 T cells were characterized by 20–25% polyfunctional cells (IL-2⁺, IFN-γ⁺, TNF-α⁺), but whereas the majority of CD4/10.4 T cells were maintained as polyfunctional T cells throughout infection, CD8/10.4 T cells differentiated almost exclusively into effector cells (IFN-γ⁺, TNF-α⁺). Both CD4/10.4 and CD8/10.4 T cells exhibited cytotoxicity in vivo in the early phase of infection, but whereas CD4/10.4 cell mediated cytotoxicity waned during the infection, CD8/10.4 T cells exhibited increasing cytotoxic potential throughout the infection.

Conclusions/Significance

Our results show that CD4 and CD8 T cells directed to epitopes in the same antigen differ both in their kinetics and functional characteristics throughout an infection with M. tuberculosis. In addition, the observed strong expansion of CD8 T cells in the late stages of infection could have implications for the development of post exposure vaccines against latent TB.     

A Randomised Trial Evaluating the Safety and Immunogenicity of the Novel Single Oral Dose Typhoid Vaccine M01ZH09 in Healthy Vietnamese Children

Background

The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC ⁻ ssaV ⁻) ZH9 with two independently attenuating deletions. Studies in healthy adults demonstrated immunogenicity and an acceptable safety profile.

Objectives

We conducted a randomised placebo controlled, single-blind trial to evaluate the safety and immunogenicity of M01ZH09 in healthy Vietnamese children aged 5 to 14 years.

Methods

Subjects were randomly assigned to receive either a nominal dose of 5×10⁹ CFU of M01ZH09 or placebo and were followed up for 28 days. The primary safety outcome was the proportion of subjects with any adverse event attributed to M01ZH09. The primary immunogenicity endpoint was the proportion of subjects who showed a positive immune response to M01ZH09 in the Salmonella Typhi lipopolysaccharide (LPS) specific serum IgA and IgG ELISA.

Principal Findings

One hundred and fifty-one children were enrolled, 101 subjects received M01ZH09 and 50 subjects received placebo. An intention to treat analysis was conducted. There were no serious adverse events and no bacteraemias. In the M01ZH09 group, 26 (26%; 95% CI, 18–5%) of 101 subjects experienced adverse events compared to 11 (22%; 95% CI, 12–36%) of 50 subjects in the placebo group (odds ratio (OR) [95%CI]  = 1.23 [0.550–2.747]; p = 0.691). Faecal shedding of S. Typhi (Ty2 aroC ⁻ ssaV ⁻) ZH9 was detected in 51 (51%; 95% CI, 41–61%) of 100 M01ZH09 subjects. No shedding was detected beyond day 3. A positive immune response, defined as 70% increase (1.7 fold change) in LPS specific serum IgG (day 14 or 28) and/or 50% increase (1.5 fold change) in LPS specific serum IgA (day 7 or 14) from baseline was detected in 98 (97%; 95% CI, 92–99%) of 101 M01ZH09 recipients and 8 (16%; 95% CI, 7–29%) of 50 placebo recipients. Twenty-eight (100%; 95% CI, 88–100%) of 28 vaccine recipients who were evaluated in the LPS specific IgA ELISPOT assay showed a positive response compared to none of the 14 placebo recipients tested.

Conclusions

This was the first phase II trial of a novel oral candidate typhoid vaccine in children in an endemic country. M01ZH09 had an appropriate safety profile and was immunogenic in children.

Trial Registration

Controlled-trials.comISRCTN91111837     

Recovery of blood gases and haematological parameters upon anaesthesia with benzocaine,MS-222 or Aqui-S in the air-breathing catfish <Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis>

Fish anaesthesia is used to minimize handling stress and damage during harvesting, transportation, and surgical procedures. Through depression of cardiovascular and respiratory functions, it causes significant changes in blood gases and pH. Here, we present the effects of benzocaine (100 mg l^?1), MS-222 (100 mg l^?1), and Aqui-S (30 mg l^?1) on blood gases and haematological parameters of commercial-sized (≈1 kg) striped catfish (Pangasianodon hypophthalmus) and the time course of recovery. Blood was taken through a dorsal aorta catheter immediately after catheterization, and regularly during the following 72 h recovery in aerated water. All anaesthetics caused increases in PCO₂ and lactate resulting in a decrease in pH_e, closely mirrored by RBC pH_i, as well as a marked rise in Hct, associated with elevated [cortisol] and [glucose] and increased RBC counts but no change in RBC volume, as confirmed by the lack of an adrenergic response of RBC in vitro. All anaesthetics showed similar efficacy and blood parameters were normalized within 24 to 48 h.     

Occurrence of two types of larvae of the Asian seaperch (<Emphasis Type="Italic">Lateolabrax</Emphasis>) in the estuaries of northern Vietnam

Lateolabrax sp. larvae were collected in the Tien Yen and Kalong estuaries of northern Vietnam, the southernmost locality for this genus distribution. Vietnamese Lateolabrax sp. larvae could be distinguished from those of L. japonicus by pigmentation patterns. Their morphological, meristic and pigmentation characters were closer to those of Chinese Lateolabrax than L. japonicus, so Vietnamese Lateolabrax is likely situated as a population of the Chinese one. Morphometric and pigmentation characters of larvae from the two estuaries differed, suggesting that Lateolabrax of northern Vietnam are diversified and consist of at least two different breeding stocks.