High Prevalence of Beijing and EAI4-VNM Genotypes among M. tuberculosis Isolates in Northern Vietnam: Sampling Effect,Rural and Urban Disparities

A total of 221 isolates of M. tuberculosis were sampled from hospitals and the general population in the northern plain of Vietnam, one of the most populated region of the country. Genotypic composition and diversity were characterized, and we investigated how they are affected by sampling (hospital vs. general population), correcting for potential confounding effects (location, age and gender of the patients). Spoligotyping and 12 MIRU-VNTR typing were used as first line. Then 15 MIRU-VNTR standard set was used, making 21 MIRU-VNTR typing for the clustered isolates. Result showed that 8 lineages and 13 sub-lineages were circulating in the region. The most predominant lineages were Beijing (38.5%) and EAI (38.5%). Others appeared with small proportions H (1.4%), LAM (1.8%), T (8.1%), X (0.9%), MANU (2.3%), and Zero (0.4%). Higher clustering rate was found in the hospital samples (17.9% in urban and 19.2% in rural areas) compared to the population ones (0%). The typical Vietnamese EAI4-VNM sub-lineage of EAI lineage accounted for 67% of EAI strains and was associated with older ages. Beijing genotypes were associated with younger, urban population and were characterized by high clustering rates. These characteristics strongly suggest that Beijing strains are invading the population, replacing the local EAI-VNM4, thus predicting a more serious tuberculosis situation in the future in the absence of more effective control strategies.     

Structure–activity relationships of the 1-amino-3-(1H-indol-1-yl)-3-phenylpropan-2-ol series of monoamine reuptake inhibitors

The SAR of a series of 1-amino-3-(1H-indol-1-yl)-3-phenylpropan-2-ols as monoamine reuptake inhibitors, with a goal to improve both potency toward inhibiting the norepinephrine transporter and selectivity over the serotonin transporter, is reported. The effect of specific substitution on both the 3-phenyl group and the indole moiety were explored. This study led to the discovery of compound 20 which inhibited the norepinephrine transporter with an IC₅₀ value of 4 nM while exhibiting 86-fold selectivity over the serotonin transporter.     

1H-NMR study of the metabolome of an exceptionally anoxia tolerant vertebrate, the crucian carp (Carassius carassius)

The crucian carp (Carassius carassius) can tolerate anoxia for days to months, depending on the temperature. In this study, we applied ¹H-NMR-based metabolomics to polar extracts of crucian carp brain, heart, muscle and liver samples obtained from fish exposed to either control normoxic conditions, acute anoxia (24 h), chronic anoxia (1 week) or reoxygenation (for 1 week following chronic anoxia) at 5 °C. Spectra of the examined tissues revealed changes in several energy-related compounds. In particular, anoxic stress resulted in decreased concentrations of phosphocreatine (muscle, liver) and glycogen (liver) and ATP/ADP (liver, heart and muscle) and increased concentrations of lactate (brain, heart, muscle) and beta-hydroxybutyric acid (all tissues). Likewise, increased concentrations of inhibitory compounds (glycine, gamma-amino butyric acid or GABA) and decreased concentrations of excitatory metabolites (glutamate, glutamine) were confirmed in the anoxic brain extracts. Additionally, a decrease of N-acetylaspartate (NAA), an important neuronal marker, was also observed in anoxic brains. The branched-chain amino acids (BCAA) valine/isoleucine/leucine increased in all anoxic tissues. Possibly, this general tissue increase can be due to an inhibited mitochondrial function or due to protein degradation/protein synthesis inhibition. In this study, the potential and strength of the ¹H-NMR is highlighted by the detection of previously unrecognized changes in metabolites. Specifically, myo-inositol substantially decreased in the heart of anoxic crucian carp and anoxic muscle tissue displayed a decreased concentration of taurine, providing novel insights into the anoxia responses of the crucian carp.     

Reproductive Strategies of the Insidious Fish Ectoparasite,Neobenedenia sp. (Capsalidae: Monogenea)

Fish monogeneans are lethal parasites in aquaculture. We provide the first experimental evidence that a notorious fish monogenean, Neobenedenia sp., can produce viable eggs in isolation for three consecutive generations. We infected individual, isolated, farmed barramundi, Lates calcarifer (Bloch) with a single oncomiracidium (larva) of the hermaphroditic monogenean Neobenedenia sp. Isolated parasites reached sexual maturity at day 10 post-hatch (24°C, 35‰) and laid ∼3,300 embryonated eggs over 17 days. Egg production rapidly increased following sexually maturity on day 10 (58±15 eggs) and peaked on day 15 (496±68 eggs) before gradually decreasing. Neobenedenia sp. exhibited egg laying and egg hatching rhythms. Parasites laid eggs continuously, but egg production increased in periods of darkness (64.3%), while the majority of oncomiracidia (81%) emerged from eggs in the first three hours of light. Eggs laid by isolated ‘parent’ parasites hatched and individual emerging oncomiracidia were used to infect more individual, isolated fish, with three consecutive, isolated, parasite generations (F1, F2 and F3) raised in the laboratory. Infection success and egg hatching success did not differ between generations. Our data show that one parasite, in the absence of a mate, presents a severe threat to captive fish populations.     

Multiple interactions of NaHER1 protein with abscisic acid signaling in Nicotiana attenuata plants

Previously, we identified a novel herbivore elicitor-regulated protein in Nicotiana attenuata (NaHER1) that is required to suppress abscisic acid (ABA) catabolism during herbivore attack and activate a full defense response against herbivores. ABA, in addition to its newly defined role in defense activation, mainly controls seed germination and stomatal function of land plants. Here we show that N. attenuata seeds silenced in the expression of NaHER1 by RNA interference (irHER1) accumulated less ABA during germination, and germinated faster on ABA-containing media compared to WT. Curiously, epidermal cells of irHER1 plants were wrinkled, possibly due to the previously demonstrated increase in transpiration of irHER1 plants that may affect turgor and cause wrinkling of the cells. We conclude that NaHER1 is a highly pleiotropic regulator of ABA responses in N. attenuata plants.     

Toward understanding MHC disease associations: partial resequencing of 46 distinct HLA haplotypes

We carried out a resequencing project that examined 552 kb of sequence from each of 46 individual HLA haplotypes representing a diversity of HLA allele types, generating nearly 27 Mb of fully phased genomic sequence. Haplotype blocks were defined extending from telomeric of HLA-F to centromeric of HLA-DP including in total 5186 MHC SNPs. To investigate basic questions about the evolutionary origin of common HLA haplotypes, and to obtain an estimate of rare variation in the MHC, we similarly examined two additional sets of samples. In 19 independent HLA-A1, B8, DR3 chromosomes, the most common HLA haplotype in Northern European Caucasians, variation was found at 11 SNP positions in the 3600-kb region from HLA-A to DR. Partial resequencing of 282 individuals in the gene-dense class III region identified significant variability beyond what could have been detected by linkage to common SNPs.     

Structural and functional studies of mammalian progesterone receptors

During the past years there has been an improvement in our understanding of the molecular mechanism of action of the progesterone receptor (PR). This was due to the obtention of monoclonal antibodies against PR which allowed the first structural analyses and led to the cloning of the genes.     

Immune evasion of porcine reproductive and respiratory syndrome virus through glycan shielding involves both glycoprotein 5 as well as glycoprotein 3

Passive administration of porcine reproductive and respiratory syndrome virus (PRRSV) neutralizing antibodies (NAbs) can effectively protect pigs against PRRSV infection. However, after PRRSV infection, pigs typically develop a weak and deferred NAb response. One major reason for such a meager NAb response is the phenomenon of glycan shielding involving GP5, a major glycoprotein carrying one major neutralizing epitope. We describe here a type II PRRSV field isolate (PRRSV-01) that is highly susceptible to neutralization and induces an atypically rapid, robust NAb response in vivo. Sequence analysis shows that PRRSV-01 lacks two N-glycosylation sites, normally present in wild-type (wt) PRRSV strains, in two of its envelope glycoproteins, one in GP3 (position 131) and the other in GP5 (position 51). To determine the influence of these missing N-glycosylation sites on the distinct neutralization phenotype of PRRSV-01, a chimeric virus (FL01) was generated by replacing the structural genes of type II PRRSV strain FL12 cDNA infectious clone with those from PRRSV-01. N-glycosylation sites were reintroduced into GP3 and GP5 of FL01, separately or in combination, by site-directed mutagenesis. Reintroduction of the N-glycosylation site in either GP3 or GP5 allowed recovery of in vivo and in vitro glycan shielding capacity, with an additive effect when these sites were reintroduced into both glycoproteins simultaneously. Although the loss of these glycosylation sites has seemingly occurred naturally (presumably by passage through cell cultures), PRRSV-01 virus quickly regains these glycosylation sites through replication in vivo, suggesting that a strong selective pressure is exerted at these sites. Collectively, our data demonstrate the involvement of an N-glycan moiety located in GP3 in glycan shield interference.     

A new species of Rhinolophus (Chiroptera: Rhinolophidae) from China

A new species of the genus Rhinolophus is described from Yunnan Province, southwestern China. The new taxon belongs to the Rhinolophus "philippinensis-group" and is distinguished by differences in the nose-leaf structures, craniodental characteristics, and bacular features.