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Numerous epidemiological studies link vascular disorders, such as hypertension, diabetes mellitus, and stroke, with Alzheimer's disease (AD). Hypertension, specifically, is an important modifiable risk factor for late-onset AD. To examine the link between midlife hypertension and the onset of AD later in life, we chemically induced chronic hypertension in the TgSwDI mouse model of AD in early adulthood. Hypertension accelerated cognitive deficits in the Barnes maze test (P<0.05 after 3 months of treatment; P<0.001 after 6 months), microvascular deposition of -amyloid (P<0.001 after 3 months of treatment; P<0.05 after 6 months), vascular inflammation (P<0.05 in the dentate gyrus and P<0.001 in the dorsal subiculum after 6 months of treatment), blood-brain barrier leakage (P<0.05 after 3 and 6 months of treatment), and pericyte loss (P<0.05 in the dentate gyrus and P<0.01 in the dorsal subiculum after 6 months of treatment) in these mice. In addition, hypertension induced hippocampal neurodegeneration at an early age in this mouse line (43% reduction in the dorsal subiculum; P<0.05), establishing this as a useful research model of AD with mixed vascular and amyloid pathologies.

Purpose of reviewPreexposure prophylaxis (PrEP) with daily Truvada has demonstrated clinical efficacy against HIV-1 acquisition that correlates with high adherence. Long-acting antiretroviral drugs offer an alternative to daily regimens and may improve PrEP adherence. This review summarizes the preclinical nonhuman primate studies for evaluating the efficacy of cabotegravir long-acting as PrEP and the ongoing phase 2a studies assessing safety, tolerability, and acceptability of cabotegravir long-acting.Recent findingsCabotegravir is an HIV-1 integrase strand transfer inhibitor with intrinsic properties that permit its formulation as a long-acting injectable suspension. In clinical evaluation, cabotegravir long-acting has a half-life that permits infrequent dosing, possibly once every 3 months. In validated macaque models, cabotegravir long-acting demonstrated high protection against both rectal and vaginal transmission at clinically achievable drug concentrations.SummaryPrEP, after approval of Truvada, continues to evolve to address adherence limitations of daily dosing. As a long-acting injectable antiretroviral drug, cabotegravir long-acting permits quarterly dosing and demonstrated high efficacy in macaque models supporting dose selection and clinical development. Clinical studies have confirmed dose selection in phase 2a trials with cabotegravir long-acting to ultimately lead to phase 2b/3 PrEP efficacy trials.

A major challenge in current exome sequencing in autosomal recessive (AR) families is the lack of an effective method to prioritize single-nucleotide variants (SNVs). AR families are generally too small for linkage analysis, and length of homozygous regions is unreliable for identification of causative variants. Various common filtering steps usually result in a list of candidate variants that cannot be narrowed down further or ranked. To prioritize shortlisted SNVs we consider each homozygous candidate variant together with a set of SNVs flanking it. We compare the resulting array of genotypes between an affected family member and a number of control individuals and argue that, in a family, differences between family member and controls should be larger for a pathogenic variant and SNVs flanking it than for a random variant. We assess differences between arrays in two individuals by the Hamming distance and develop a suitable test statistic, which is expected to be large for a causative variant and flanking SNVs. We prioritize candidate variants based on this statistic and applied our approach to six patients with known pathogenic variants and found these to be in the top 2 to 10 percentiles of ranks.

Results are reported of a general search for pair production of heavy resonances decaying to pairs of hadronic jets in events with at least four jets. The study is based on up to 19.4 fb(-1) of integrated luminosity from proton-proton collisions at a center-of-mass energy of 8 TeV, recorded with the CMS detector at the LHC. Limits are determined on the production of scalar top quarks (top squarks) in the framework of R-parity violating supersymmetry and on the production of color-octet vector bosons (colorons). First limits at the LHC are placed on top squark production for two scenarios. The first assumes decay to a bottom quark and a light-flavor quark and is excluded for masses between 200 and 385 GeV, and the second assumes decay to a pair of light-flavor quarks and is excluded for masses between 200 and 350 GeV at 95% confidence level. Previous limits on colorons decaying to light-flavor quarks are extended to exclude masses from 200 to 835 GeV. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license.

Fms-like tyrosine kinase-3 ligand (Flt3L) uniquely binds the Flt3 (CD135) receptor expressed on hematopoietic stem cells (HSCs), early progenitor cells, immature thymocytes and steady-state dendritic cells (DCs) and induces their proliferation, differentiation, development and mobilization in the bone marrow, peripheral blood and lymphoid organs. CDX-301 has an identical amino-acid sequence and comparable biological activity to the previously tested rhuFlt3L, which ceased clinical development over a decade ago. This Phase 1 trial assessed the safety, pharmacokinetic, pharmacodynamic and immunologic profile of CDX-301, explored alternate dosing regimens and examined the impact of rhuFlt3L on key immune cell subsets. Thirty healthy volunteers received CDX-301 (1-75 mu g/kg/day) over 5-10 days. One event of Grade 3 community-acquired pneumonia occurred. There were no other infections, dose-limiting toxicities or serious adverse events. CDX-301 resulted in effective peripheral expansion of monocytes, hematopoietic stem and progenitor cells and key subsets of myeloid DCs and plasmacytoid DCs, with no clear effect on regulatory T cells. These data from healthy volunteers support the potential for CDX-301, as monotherapy or in combination with other agents, in various indications including allogeneic HSC transplantation and immunotherapy, but the effects of CDX-301 will need to be investigated in each of these patient populations.

Dynamic remodelling of intersubunit bridge B2, a conserved RNA domain of the bacterial ribosome connecting helices 44 (h44) and 69 (H69) of the small and large subunit, respectively, impacts translation by controlling intersubunit rotation. Here we show that aminoglycosides chemically related to neomycin-paromomycin, ribostamycin and neamine-each bind to sites within h44 and H69 to perturb bridge B2 and affect subunit rotation. Neomycin and paromomycin, which only differ by their ring-I 6'-polar group, drive subunit rotation in opposite directions. This suggests that their distinct actions hinge on the 6'-substituent and the drug's net positive charge. By solving the crystal structure of the paromomycin-ribosome complex, we observe specific contacts between the apical tip of H69 and the 6'-hydroxyl on paromomycin from within the drug's canonical h44-binding site. These results indicate that aminoglycoside actions must be framed in the context of bridge B2 and their regulation of subunit rotation.

Deep dermatophytosis has been described in HIV and immunosuppressed patients. Recently, CARD9 (caspase recruitment domain-containing protein 9) deficiency has been reported in individuals with deep dermatophytosis previously classified as "immunocompetent". We report a 24-year-old Brazilian male patient with deep dermatophytosis born to an apparently non-consanguineous family. The symptoms started with oral candidiasis when he was 3 years old, persistent although treated. At 11 years old, well delimited, desquamative and pruriginous skin lesions appeared in the mandibular area; ketoconazole and itraconazole were introduced and maintained for 5 years. At 12 years of age, the lesions, which initially affected the face, started to spread to thoracic and back of the body (15 cm of diameter) and became ulcerative, secretive and painful. Terbinafine was introduced without any improvement. Trichophyton mentagrophytes was isolated from the skin lesions. A novel homozygous mutation in CARD9 (R101L) was identified in the patient, resulting in impaired neutrophil fungal killing. Both parents, one brother (with persistent superficial but not deep dermatophytosis) and one sister were heterozygous for this mutation, while another brother was found to be homozygous for the CARD9 wild-type allele. This is the first report of CARD9 deficiency in Latin America.

Large-scale sequencing of prokaryotic (meta) genomic DNA suggests that most bacterial natural product gene clusters are not expressed under common laboratory culture conditions. Silent gene clusters represent a promising resource for natural product discovery and the development of a new generation of therapeutics. Unfortunately, the characterization of molecules encoded by these clusters is hampered owing to our inability to express these gene clusters in the laboratory. To address this bottleneck, we have developed a promoter-engineering platform to transcriptionally activate silent gene clusters in a model heterologous host. Our approach uses yeast homologous recombination, an auxotrophy complementation-based yeast selection system and sequence orthogonal promoter cassettes to exchange all native promoters in silent gene clusters with constitutively active promoters. As part of this platform, we constructed and validated a set of bidirectional promoter cassettes consisting of orthogonal promoter sequences, Streptomyces ribosome binding sites, and yeast selectable marker genes. Using these tools we demonstrate the ability to simultaneously insert multiple promoter cassettes into a gene cluster, thereby expediting the reengineering process. We apply this method to model active and silent gene clusters (rebeccamycin and tetarimycin) and to the silent, cryptic pseudogene-containing, environmental DNA-derived Lzr gene cluster. Complete promoter refactoring and targeted gene exchange in this "dead" cluster led to the discovery of potent indolotryptoline antiproliferative agents, lazarimides A and B. This potentially scalable and cost-effective promoter reengineering platform should streamline the discovery of natural products from silent natural product biosynthetic gene clusters.

Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD.