Fate of thiamethoxam from treated seeds in mesocosms and response of aquatic invertebrate communities

Thiamethoxam is a neonicotinoid insecticide widely applied in the Canadian Prairies. It has been detected in surface waters of agro-ecosystems, including wetlands, but the potential effects on non-target invertebrate communities in these wetlands have not been well characterized. In an effort to understand better the fate of thiamethoxam in wetlands and the response of invertebrates (zooplankton and emergent insects), model systems were used to mimic wetland flooding into planted fields. Outdoor mesocosms were treated with a single application of thiamethoxam-treated canola seeds at three treatment levels based on a recommended seeding rate (i.e., 6 kg/ha; 1×, 10×, and 100× seeding rate) and monitored over ten weeks. The mean half-life of thiamethoxam in the water column was 6.2 d. There was no ecologically meaningful impact on zooplankton abundances or community structure among treatments. Statistically significant differences were observed in aquatic insect abundance between control mesocosms and the two greatest thiamethoxam treatments (10× and 100× seeding rate). The observed results indicate exposure to thiamethoxam at environmentally relevant concentrations likely does not represent a significant ecological risk to abundance and community structure of wetland zooplankton and emergent insects.

Artificial Intelligence Platform Demonstrates High Adherence in Patients Receiving Fixed-Dose Ledipasvir and Sofosbuvir: A Pilot Study

This study evaluated health outcomes among people who inject drugs who are infected with hepatitis C virus using an artificial intelligence platform. Mean (SD) cumulative adherence (visual confirmation of administration) was 91.3% (10.5%). Most subjects (88.2%) achieved ≥80% adherence to treatment, and 88.2% (15 of 17) achieved a sustained virologic response.

Identification of genomic islands in Chilean Piscirickettsia salmonis strains and analysis of gene expression involved in virulence

Piscirickettsia salmonis, an agent of Piscirickettsiosis, is the cause of major losses in the Chilean salmon industry. We identified, characterized and bioinformatically analysed genomic islands in field strains of P. Salmonis, using the bioinformatic software PIPS, that uses the characteristics of the islands of pathogenicity to identify them. We analysed nine partially sequenced genomes in different new field strains, and compared them with the LF-89 (Type strain) genome, selecting a genomic island present in all of them. We then evaluated the relative expression of three genes present in that island. From the obtained results, we conclude that the expression of the tcf gene is directly proportional to the cytopathogenicity in vitro of the bacteria; the product of the dnsa gene could contribute to its pathogenicity, but would be potentiated by one or more factors. The product of the gene liso is necessary for the virulence process and could have functions in early stages of infection. Regarding the strains, the IBM-040 strain showed a significant increase in the expression of all the genes in the study. Contrarily, LF-89 only presented a significant increase in expression of the gene liso, which correlates with the cytopathogenicity in vitro observed in the SHK-1 cells.

Identification of the clpB and bipA genes and an evaluation of their expression as related to intracellular survival for the bacterial pathogen Piscirickettsia salmonis

Piscirickettsia salmonis is the pathogen responsible for salmonid rickettsial septicemia (SRS), a disease that affects a wide variety of marine cultivated fish species and causes economic losses for the aquaculture industry worldwide. Many in vitro studies have reported on the capacity of this microorganism to replicate in the interior of cytoplasmic vesicles from varied fish cell lines. However, the mechanisms used by this bacteria to survive, replicate, and propagate in cell lines, especially in macrophages and monocytes, are unknown. A number of studies have described the diverse proteins in pathogens such as Legionella pneumophila, Coxiella burnetii, and Francisella tularensis which allow these to evade the cellular immune response and replicate in the interior of macrophages in different hosts. Some of these proteins are the virulence factor BipA/TypA and the heat shock protein ClpB, both of which have been widely characterized. The results of the current study present the complete coding sequence of the genes clpB and bipA from the P. salmonis genome. Moreover, the experimental results suggest that during the infectious process of the SHK-1 cellular line in P. salmonis, the pathogen significantly increases the expression of proteins ClpB and BipA. This would permit the pathogen to adapt to the hostile conditions produced by the macrophage and thus evade mechanisms of cellular degradation while facilitating replication in the interior of this salmon cell line.

At least two expressed genes for transcription factors Pitx2 and Rpx are present in common carp and are upregulated during winter acclimatization

The mechanisms of seasonal acclimatization in eurythermal fish such as common carp are not fully understood. Here, we concentrate on the regulation of pituitary factors, as this organ was shown to be highly affected by seasonal changes. We cloned and sequenced two different cDNAs for each of the transcription factors Pitx2 and Rpx, known to play a role in pituitary development. We show that these genes are conserved throughout evolution, to different degrees depending on the specific domain considered. Finally, we show that the cDNAs for both factors are clearly up-regulated during the winter season, in sharp contrast to other regulators such as Pit1 or pituitary hormone genes such as prolactin (prl) and growth hormone (gh). Our results suggest that increased expression of Pitx2 and Rpx contributes to seasonal adaptation of common carp to winter conditions.

Heme oxygenase-1 induction does not improve vascular relaxation in angiotensin II hypertensive mice

BACKGROUND

Induction of heme oxygenase-1 (HO-1) attenuates the development of angiotensin II (Ang II)-dependent hypertension in mice. However, the mechanism by which HO-1 lowers blood pressure in this model is not clear. This study was designed to determine whether induction of HO-1 results in an improvement in vascular relaxation in Ang II hypertensive mice.

METHODS

Mice were treated with either of the vehicles (control), the HO-1 inducer cobalt protoporphyrin (CoPP;50 mg/kg), Ang II(1 microg/kg/min, 14 days), or Ang II + CoPP. CoPP was administered as a single bolus dose 2 days prior to subcutaneous implantation of the osmotic minipump containing Ang II. Vascular relaxation was examined in isolated carotid arteries precontracted with the thromboxane mimetic U46619 (0.4 microg/ml).

RESULTS

Endothelial dependent relaxation to acetylcholine (ACh; 1 micromol/l) was significantly impaired in Ang II-treated mice compared to control mice (56 +/- 3% vs. 40 +/- 4%, P < 0.05, n > or = 6). Similarly, endothelial independent relaxation to sodium nitroprusside (SNP; 1 micromol/l) was significantly impaired in Ang II mice (56 +/- 6% vs. 28 +/- 6%, P < 0.05, n > or = 6). Relaxation in response to the carbon monoxide donor, CORM-A1 (100 micromol/l), was attenuated after Ang II treatment (75 +/- 7% vs. 59 +/- 7%,P < 0.05, n > or = 6). CoPP treatment induced HO-1 but not HO-2 protein in the aorta, as measured by western blot analysis. CoPP treatment had no effect on vascular responses in control mice and did not improve ACh (26 +/- 5%, n = 15), SNP (23 +/- 4%, n = 15), or CORM-A1 (46 +/- 7%, n = 10) dependent relaxation in Ang II treated mice.

CONCLUSIONS

These results suggest that induction of HO-1 lowers Ang II-dependent hypertension through a mechanism independent of improved vascular relaxation.

Modular changes of cis-regulatory elements from two functional Pit1 genes in the duplicated genome of Cyprinus carpio

The pituitary-specific transcription factor Pit1 is involved in its own regulation and in a network of transcriptional regulation of hypothalamo-hypophyseal factors including prolactin (PRL) and growth hormone (GH). In the ectotherm teleost Cyprinus carpio, Pit1 plays an important role in regulation of the adaptive response to seasonal environmental changes. Two Pit1 genes exist in carp, a tetraploid vertebrate and transcripts of both genes were detected by RT-PCR analysis. Powerful comparative analyses of the 5'-flanking regions revealed copy specific changes comprising modular functional units in the naturally evolved promoters. These include the precise replacement of four nucleotides around the transcription start site embedded in completely conserved regions extending upstream of the TATA-box, an additional transcription factor binding site in the 5'-UTR of gene-I and, instead, duplication of a 9 bp element in gene-II. Binding of nuclear factors was assessed by electro mobility shift assays using extracts from rat pituitary cells and carp pituitary. Binding was confirmed at one conserved Pit1, one conserved CREB and one consensus MTF1. Interestingly, two functional Pit1 sites and one putative MTF1 binding site are unique to the Pit1 gene-I. In situ hybridization experiments revealed that the expression of gene-I in winter carp was significantly stronger than that of gene-II. Our data suggest that the specific control elements identified in the proximal regulatory region are physiologically relevant for the function of the duplicated Pit1 genes in carp and highlight modular changes in the architecture of two Pit1 genes that evolved for at least 12 MYA in the same organism.

First established pregnancy and birth after induction of ovulation with recombinant human follicle stimulating hormone during in vitro fertilization-embryo transfer and intracytoplasmic sperm injection

This case report describes the first established pregnancy and birth in the Philippines after induction of ovulation with recombinant follicle stimulating hormone (rec FSH) during In Vitro Fertilization-Embryo Transfer (IVF-ET) and Intracytoplasmic Sperm Injection (ICSI) in a Filipino woman with pelvic endometriosis who underwent right oophorectomy for endometrioma 1 year prior to IVF-ET and ICSI. Husband's semenalysis revealed adequate volume with 10% normal forms. Gonadotrophin releasing hormone agonist (Lupron) 375 mg subcutaneous was given for 2 cycles. 100 IU B.I.D. (a total of 2200 IU) of rec FSH was administered intramuscularly daily with single preovulatory follicle seen upon transvaginal ultrasonographic examination of 10,000 IU of human chorionic gonadotrophin, after which a viable singleton pregnancy was revealed at a gestational age of 8 weeks. The course of pregnancy until term was uneventful and ended with abdominal delivery at a gestational age of 37.3 weeks secondary to poor Fetopelvic Index with oligohydramnios. A healthy girl was born and pediatric examination did not demonstrate any abnormality.