Pharmacological studies on STb heat-stable enterotoxin in pig and rat jejunum

The effects of Eschericihia coli heat-stable enterotoxin, STb, on the jejunum of pigs (three to six weeks old) and rats (250 to 350 g) were examined. In vivo and in vitro techniques consisting of ligated loops, perfused segments and isolated enterocytes were employed in the study. STb induced secretion or decreased absorption of water, sodium, potassium and chloride in vivo. Soybean trypsin inhibitor significantly increased the STb induced secretion of water in the perfused rat intestine. This suggests that trypsin-like compounds present in the jejunum reduce the activity of STb. Neither the influx of calcium nor the influx or efflux of chloride was altered by STb in the isolated enterocytes;Clonidine reduced or reversed the effect of STb on water and electrolyte transport in the pig perfusion and ligated loop studies. Morphine displayed similar effects in the ligated loops of pigs. Neither drug had any effect in the ligated loops of rats. The muscarinic antagonist 4-Diphenylacetoxy-N-methyl piperidine (4-DAMP) reduced the effect of STb on water transport in rat intestine while pirenzepine, also a muscarinic antagonist, exhibited no effect;Leucine and methionine enkephalin and loperamide had no effect on the secretory effect of STb in rat ligated intestinal loops. Chloride absorption under the influence of STb was increased by the addition of hexamethonium and scopolamine in pig ligated loops

Assessment of the onset of action of afoxolaner against existing adult flea (Ctenocephalides felis) infestations on dogs

AbstractThe speed of kill of afoxolaner against experimental infestations by Ctenocephalides felis was evaluated after oral administration of afoxolaner in a soft chew (NEXGARD®) at a dose to achieve 2.5mg/kg bodyweight. Forty beagles were allocated to two treatment groups. Dogs in Treatment Group 1 were untreated controls. Dogs in Treatment Group 2 were treated on Day-0 with afoxolaner, according to their pre-treatment bodyweight. All dogs were infested with approximately 100 C. felis on Day-1. Live fleas were counted upon removal at 5 time points after treatment (i.e., 2, 4, 8, 12 and 24h after treatment). For each time point, counts were performed on 4 dogs from each of the treated and the untreated groups. Early curative flea killing efficacy was evaluated with respect to the untreated control group. The afoxolaner treated group had significantly fewer fleas than the untreated control group at 8, 12, and 24h (p<0.001). The percent efficacies of orally administered afoxolaner were 15.0%, 87.8%, 99.5%, 100.0%, and 100.0% at 2, 4, 8, 12, and 24h, respectively. In this study, afoxolaner began killing fleas by 2h after treatment with increasing efficacy at subsequent time points and had >99.5% efficacy at 8, 12, and 24h after treatment demonstrating an early onset of action

Convergent genetic and expression data implicate immunity in Alzheimer's disease

Background Late–onset Alzheimer's disease (AD) is heritable with 20 genes showing genome wide association in the International Genomics of Alzheimer's Project (IGAP). To identify the biology underlying the disease we extended these genetic data in a pathway analysis. Methods The ALIGATOR and GSEA algorithms were used in the IGAP data to identify associated functional pathways and correlated gene expression networks in human brain. Results ALIGATOR identified an excess of curated biological pathways showing enrichment of association. Enriched areas of biology included the immune response (p = 3.27×10-12 after multiple testing correction for pathways), regulation of endocytosis (p = 1.31×10-11), cholesterol transport (p = 2.96 × 10-9) and proteasome-ubiquitin activity (p = 1.34×10-6). Correlated gene expression analysis identified four significant network modules, all related to the immune response (corrected p 0.002 – 0.05). Conclusions The immune response, regulation of endocytosis, cholesterol transport and protein ubiquitination represent prime targets for AD therapeutics

Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

A novel Alzheimer disease locus located near the gene encoding tau protein

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordAPOE ε4, the most significant genetic risk factor for Alzheimer disease (AD), may mask effects of other loci. We re-analyzed genome-wide association study (GWAS) data from the International Genomics of Alzheimer's Project (IGAP) Consortium in APOE ε4+ (10 352 cases and 9207 controls) and APOE ε4- (7184 cases and 26 968 controls) subgroups as well as in the total sample testing for interaction between a single-nucleotide polymorphism (SNP) and APOE ε4 status. Suggestive associations (P<1 × 10-4) in stage 1 were evaluated in an independent sample (stage 2) containing 4203 subjects (APOE ε4+: 1250 cases and 536 controls; APOE ε4-: 718 cases and 1699 controls). Among APOE ε4- subjects, novel genome-wide significant (GWS) association was observed with 17 SNPs (all between KANSL1 and LRRC37A on chromosome 17 near MAPT) in a meta-analysis of the stage 1 and stage 2 data sets (best SNP, rs2732703, P=5·8 × 10-9). Conditional analysis revealed that rs2732703 accounted for association signals in the entire 100-kilobase region that includes MAPT. Except for previously identified AD loci showing stronger association in APOE ε4+ subjects (CR1 and CLU) or APOE ε4- subjects (MS4A6A/MS4A4A/MS4A6E), no other SNPs were significantly associated with AD in a specific APOE genotype subgroup. In addition, the finding in the stage 1 sample that AD risk is significantly influenced by the interaction of APOE with rs1595014 in TMEM106B (P=1·6 × 10-7) is noteworthy, because TMEM106B variants have previously been associated with risk of frontotemporal dementia. Expression quantitative trait locus analysis revealed that rs113986870, one of the GWS SNPs near rs2732703, is significantly associated with four KANSL1 probes that target transcription of the first translated exon and an untranslated exon in hippocampus (P≤1.3 × 10-8), frontal cortex (P≤1.3 × 10-9) and temporal cortex (P≤1.2 × 10-11). Rs113986870 is also strongly associated with a MAPT probe that targets transcription of alternatively spliced exon 3 in frontal cortex (P=9.2 × 10-6) and temporal cortex (P=2.6 × 10-6). Our APOE-stratified GWAS is the first to show GWS association for AD with SNPs in the chromosome 17q21.31 region. Replication of this finding in independent samples is needed to verify that SNPs in this region have significantly stronger effects on AD risk in persons lacking APOE ε4 compared with persons carrying this allele, and if this is found to hold, further examination of this region and studies aimed at deciphering the mechanism(s) are warranted

Pharmacological studies on STb heat-stable enterotoxin in pig and rat jejunum

The effects of Eschericihia coli heat-stable enterotoxin, STb, on the jejunum of pigs (three to six weeks old) and rats (250 to 350 g) were examined. In vivo and in vitro techniques consisting of ligated loops, perfused segments and isolated enterocytes were employed in the study. STb induced secretion or decreased absorption of water, sodium, potassium and chloride in vivo. Soybean trypsin inhibitor significantly increased the STb induced secretion of water in the perfused rat intestine. This suggests that trypsin-like compounds present in the jejunum reduce the activity of STb. Neither the influx of calcium nor the influx or efflux of chloride was altered by STb in the isolated enterocytes;Clonidine reduced or reversed the effect of STb on water and electrolyte transport in the pig perfusion and ligated loop studies. Morphine displayed similar effects in the ligated loops of pigs. Neither drug had any effect in the ligated loops of rats. The muscarinic antagonist 4-Diphenylacetoxy-N-methyl piperidine (4-DAMP) reduced the effect of STb on water transport in rat intestine while pirenzepine, also a muscarinic antagonist, exhibited no effect;Leucine and methionine enkephalin and loperamide had no effect on the secretory effect of STb in rat ligated intestinal loops. Chloride absorption under the influence of STb was increased by the addition of hexamethonium and scopolamine in pig ligated loops.</p

Study to evaluate the acaricidal efficacy of a single topical treatment with a topical combination of fipronil/amitraz/(S)-methoprene against Dermacentor variabilis on dogs

The objective of the study was to confirm the acaricidal efficacy of a single topical treatment of the combination of fipronil/amitraz/(S)-methoprene (CERTIFECT®) against induced infestations of Dermacentor variabilis. Sixteen healthy mixed breed mongrels (8 males and 8 females), approximately 9.6 to 13.7 months of age on Day 0, and weighing 16.2 to 33.4 lbs, were selected from a group of 20 dogs based on Day -1 pre-treatment tick counts to be utilized in this randomized, blinded efficacy study. Eight dogs were randomly assigned to one of the two treatment groups: Group 1 - placebo (vehicle), Group 2 - fipronil/amitraz/(S)-methoprene (delivering at least 6.7mg fibronil/kg body weight (bw), 8.0 mg amitraz/kg bw, and 6.0 mg (S)-methoprene/kg bw). The vehicle or treatment was applied directly onto the skin at two separate spots on the neck of each dog, once on Day 0, per label dose and directions for use. All dogs were infested with 50 (±5) unfed adult D. variabilis on Day 1, then weekly on days 7, 14, 21, 28, and 35. Ticks were thumb counted at 24 (±3) hours following each tick infestation and subsequently were counted and removed from each dog at 48 (±3)hours after tick infestation. Thumb counts were performed on all dogs at 24 hours following each infestation. Efficacies on Days 2, 8, 15, 22, 29, and 36 were 98.6, 100, 99.7, 96.6, 86.6, and 90.1%, respectively. All dogs treated with the fipronil/amitraz/(S)-methoprene product had significantly (p<0.05) fewer ticks than placebo (vehicle-treated) control animals. Removal counts were performed at 48 hours after each infestation. Efficacies for Days 3, 9, 16, 23, 30, and 37 were 100, 100, 100, 100, 99.4, and 97.2%, respectively. Again, all dogs treated with the fipronil/amitraz/(S)-methoprene product had significantly (p<0.05) fewer ticks than placebo (vehicle-treated) control animals. No treatment related adverse events were observed during the study, including during four observations performed within 5 hours post-treatment. The results of this study confirm rapid and effective control of D. variabilis ticks on CERTIFECT-treated dogs

Cutaneous Balamuthia mandrillaris infection as a precursor to Balamuthia amoebic encephalitis (BAE) in a healthy 84-year-old Californian

Soil and freshwater-dwelling amoebae may opportunistically infect the skin and evoke a granulomatous dermatitis that camouflages their underlying morphology. Amoebic infestations are incredibly rare in the U.S., predominantly occurring in the young, elderly, and immunocompromised. Sadly, because diagnosis is difficult and unsuspected, most cases are diagnosed at autopsy. The following case is of a healthy 84-year-old man with a non-healing nodulo-ulcerative cutaneous lesion on his left forearm that appeared following a gardening injury. Lesional punch biopsies repeatedly showed non-specific granulomatous inflammation with no pathogens evident histologically or by culture. Histopathologic diagnosis was made five months after initial presentation via identification of amoebic trophozoite forms in tissue from a large excisional specimen. Anti-amoebic therapy was initiated immediately. The patient experienced mental status changes three days following lesion excision, with evidence of a cystic mass in the left medial parieto-occipital lobe by CT. Both intraoperative brain biopsies and cutaneous tissue samples tested positive for Balamuthia mandrillaris by indirect immunofluorescent antibody assay performed at the Centers for Disease Control. The patient achieved a full recovery on a triple antibiotic regimen. Clinical suspicion and thorough histopathologic analysis may determine the difference between survival and death for a patient presenting with a treatment-refractory localized granulomatous lesion