567 research outputs found
The extraordinary evolutionary history of the reticuloendotheliosis viruses
The reticuloendotheliosis viruses (REVs) comprise several closely related amphotropic retroviruses isolated from birds. These viruses exhibit several highly unusual characteristics that have not so far been adequately explained, including their extremely close relationship to mammalian retroviruses, and their presence as endogenous sequences within the genomes of certain large DNA viruses. We present evidence for an iatrogenic origin of REVs that accounts for these phenomena. Firstly, we identify endogenous retroviral fossils in mammalian genomes that share a unique recombinant structure with REVs—unequivocally demonstrating that REVs derive directly from mammalian retroviruses. Secondly, through sequencing of archived REV isolates, we confirm that contaminated Plasmodium lophurae stocks have been the source of multiple REV outbreaks in experimentally infected birds. Finally, we show that both phylogenetic and historical evidence support a scenario wherein REVs originated as mammalian retroviruses that were accidentally introduced into avian hosts in the late 1930s, during experimental studies of P. lophurae, and subsequently integrated into the fowlpox virus (FWPV) and gallid herpesvirus type 2 (GHV-2) genomes, generating recombinant DNA viruses that now circulate in wild birds and poultry. Our findings provide a novel perspective on the origin and evolution of REV, and indicate that horizontal gene transfer between virus families can expand the impact of iatrogenic transmission events
SuperCLASS - II. Photometric redshifts and characteristics of spatially resolved mu Jy radio sources
We present optical and near-infrared imaging covering a ∼1.53 deg2 region in the Super-Cluster Assisted Shear Survey (SuperCLASS) field, which aims to make the first robust weak lensing measurement at radio wavelengths. We derive photometric redshifts for ≈176 000 sources down to i′AB∼24 and present photometric redshifts for 1.4 GHz expanded Multi-Element Radio Linked Interferometer Network (e-MERLIN) and Karl G. Jansky Very Large Array (VLA) detected radio sources found in the central 0.26 deg2. We compile an initial catalogue of 149 radio sources brighter than S1.4 > 75 μJy and find their photometric redshifts span 0 7σ in the density map and we confirm the photometric redshifts are consistent with previously measured spectra from a few galaxies at the cluster centres
TbPIF5 Is a Trypanosoma brucei Mitochondrial DNA Helicase Involved in Processing of Minicircle Okazaki Fragments
Trypanosoma brucei's mitochondrial genome, kinetoplast DNA (kDNA), is a giant network of catenated DNA rings. The network consists of a few thousand 1 kb minicircles and several dozen 23 kb maxicircles. Here we report that TbPIF5, one of T. brucei's six mitochondrial proteins related to Saccharomyces cerevisiae mitochondrial DNA helicase ScPIF1, is involved in minicircle lagging strand synthesis. Like its yeast homolog, TbPIF5 is a 5′ to 3′ DNA helicase. Together with other enzymes thought to be involved in Okazaki fragment processing, TbPIF5 localizes in vivo to the antipodal sites flanking the kDNA. Minicircles in wild type cells replicate unidirectionally as theta-structures and are unusual in that Okazaki fragments are not joined until after the progeny minicircles have segregated. We now report that overexpression of TbPIF5 causes premature removal of RNA primers and joining of Okazaki fragments on theta structures. Further elongation of the lagging strand is blocked, but the leading strand is completed and the minicircle progeny, one with a truncated H strand (ranging from 0.1 to 1 kb), are segregated. The minicircles with a truncated H strand electrophorese on an agarose gel as a smear. This replication defect is associated with kinetoplast shrinkage and eventual slowing of cell growth. We propose that TbPIF5 unwinds RNA primers after lagging strand synthesis, thus facilitating processing of Okazaki fragments
Tisotumab Vedotin in Previously Treated Recurrent or Metastatic Cervical Cancer
\ua92019 American Association for Cancer Research.PURPOSE: Tissue factor (TF) is a potential target in cervical cancer, as it is frequently highly expressed and associated with poor prognosis. Tisotumab vedotin, a first-in-class investigational antibody-drug conjugate targeting TF, has demonstrated encouraging activity in solid tumors. Here we report data from the cervical cancer cohort of innovaTV 201 phase I/II study (NCT02001623). PATIENTS AND METHODS: Patients with recurrent or metastatic cervical cancer received tisotumab vedotin 2.0 mg/kg every 3 weeks until progressive disease, unacceptable toxicity, or consent withdrawal. The primary objective was safety and tolerability. Secondary objectives included antitumor activity. RESULTS: Of the 55 patients, 51% had received ≥2 prior lines of treatment in the recurrent or metastatic setting; 67% had prior bevacizumab + doublet chemotherapy. Fifty-one percent of patients had squamous cell carcinoma. The most common grade 3/4 treatment-emergent adverse events (AEs) were anemia (11%), fatigue (9%), and vomiting (7%). No grade 5 treatment-related AEs occurred. Investigator-assessed confirmed objective response rate (ORR) was 24% [95% confidence interval (CI): 13%-37%]. Median duration of response (DOR) was 4.2 months (range: 1.0+-9.7); four patients responded for >8 months. The 6-month progression-free survival (PFS) rate was 29% (95% CI: 17%-43%). Independent review outcomes were comparable, with confirmed ORR of 22% (95% CI: 12%-35%), median DOR of 6.0 months (range: 1.0+-9.7), and 6-month PFS rate of 40% (95% CI: 24%-55%). Tissue factor expression was confirmed in most patients; no significant association with response was observed. CONCLUSIONS: Tisotumab vedotin demonstrated a manageable safety profile and encouraging antitumor activity in patients with previously treated recurrent or metastatic cervical cancer
Tisotumab Vedotin in Previously Treated Recurrent or Metastatic Cervical Cancer
PURPOSE: Tissue factor (TF) is a potential target in cervical cancer, as it is frequently highly expressed and associated with poor prognosis. Tisotumab vedotin, a first-in-class investigational antibody-drug conjugate targeting TF, has demonstrated encouraging activity in solid tumors. Here we report data from the cervical cancer cohort of innovaTV 201 phase I/II study (NCT02001623). PATIENTS AND METHODS: Patients with recurrent or metastatic cervical cancer received tisotumab vedotin 2.0 mg/kg every 3 weeks until progressive disease, unacceptable toxicity, or consent withdrawal. The primary objective was safety and tolerability. Secondary objectives included antitumor activity. RESULTS: Of the 55 patients, 51% had received ≥2 prior lines of treatment in the recurrent or metastatic setting; 67% had prior bevacizumab + doublet chemotherapy. Fifty-one percent of patients had squamous cell carcinoma. The most common grade 3/4 treatment-emergent adverse events (AEs) were anemia (11%), fatigue (9%), and vomiting (7%). No grade 5 treatment-related AEs occurred. Investigator-assessed confirmed objective response rate (ORR) was 24% [95% confidence interval (CI): 13%-37%]. Median duration of response (DOR) was 4.2 months (range: 1.0+ -9.7); four patients responded for >8 months. The 6-month progression-free survival (PFS) rate was 29% (95% CI: 17%-43%). Independent review outcomes were comparable, with confirmed ORR of 22% (95% CI: 12%-35%), median DOR of 6.0 months (range: 1.0+ -9.7), and 6-month PFS rate of 40% (95% CI: 24%-55%). Tissue factor expression was confirmed in most patients; no significant association with response was observed. CONCLUSIONS: Tisotumab vedotin demonstrated a manageable safety profile and encouraging antitumor activity in patients with previously treated recurrent or metastatic cervical cancer
Randomized Controlled Caregiver Mediated Joint Engagement Intervention for Toddlers with Autism
This study aimed to determine if a joint attention intervention would result in greater joint engagement between caregivers and toddlers with autism. The intervention consisted of 24 caregiver-mediated sessions with follow-up 1 year later. Compared to caregivers and toddlers randomized to the waitlist control group the immediate treatment (IT) group made significant improvements in targeted areas of joint engagement. The IT group demonstrated significant improvements with medium to large effect sizes in their responsiveness to joint attention and their diversity of functional play acts after the intervention with maintenance of these skills 1 year post-intervention. These are among the first randomized controlled data to suggest that short-term parent-mediated interventions can have important effects on core impairments in toddlers with autism. Clinical Trials #: NCT00065910
Spatial Frequency-Based Analysis of Mean Red Blood Cell Speed in Single Microvessels: Investigation of Microvascular Perfusion in Rat Cerebral Cortex
BACKGROUND: Our previous study has shown that prenatal exposure to X-ray irradiation causes cerebral hypo-perfusion during the postnatal development of central nervous system (CNS). However, the source of the hypo-perfusion and its impact on the CNS development remains unclear. The present study developed an automatic analysis method to determine the mean red blood cell (RBC) speed through single microvessels imaged with two-photon microscopy in the cerebral cortex of rats prenatally exposed to X-ray irradiation (1.5 Gy). METHODOLOGY/PRINCIPAL FINDINGS: We obtained a mean RBC speed (0.9±0.6 mm/sec) that ranged from 0.2 to 4.4 mm/sec from 121 vessels in the radiation-exposed rats, which was about 40% lower than that of normal rats that were not exposed. These results were then compared with the conventional method for monitoring microvascular perfusion using the arteriovenous transit time (AVTT) determined by tracking fluorescent markers. A significant increase in the AVTT was observed in the exposed rats (1.9±0.6 sec) as compared to the age-matched non-exposed rats (1.2±0.3 sec). The results indicate that parenchyma capillary blood velocity in the exposed rats was approximately 37% lower than in non-exposed rats. CONCLUSIONS/SIGNIFICANCE: The algorithm presented is simple and robust relative to monitoring individual RBC speeds, which is superior in terms of noise tolerance and computation time. The demonstrative results show that the method developed in this study for determining the mean RBC speed in the spatial frequency domain was consistent with the conventional transit time method
Prevalence of HIV, syphilis, hepatitis B and C among adults with mental illness: a multicenter study in Brazil
Cryptic Diversity in Indo-Pacific Coral-Reef Fishes Revealed by DNA-Barcoding Provides New Support to the Centre-of-Overlap Hypothesis
Diversity in coral reef fishes is not evenly distributed and tends to accumulate in the Indo-Malay-Philippines Archipelago (IMPA). The comprehension of the mechanisms that initiated this pattern is in its infancy despite its importance for the conservation of coral reefs. Considering the IMPA either as an area of overlap or a cradle of marine biodiversity, the hypotheses proposed to account for this pattern rely on extant knowledge about taxonomy and species range distribution. The recent large-scale use of standard molecular data (DNA barcoding), however, has revealed the importance of taking into account cryptic diversity when assessing tropical biodiversity. We DNA barcoded 2276 specimens belonging to 668 coral reef fish species through a collaborative effort conducted concomitantly in both Indian and Pacific oceans to appraise the importance of cryptic diversity in species with an Indo-Pacific distribution range. Of the 141 species sampled on each side of the IMPA, 62 presented no spatial structure whereas 67 exhibited divergent lineages on each side of the IMPA with K2P distances ranging between 1% and 12%, and 12 presented several lineages with K2P distances ranging between 3% and 22%. Thus, from this initial pool of 141 nominal species with Indo-Pacific distribution, 79 dissolved into 165 biological units among which 162 were found in a single ocean. This result is consistent with the view that the IMPA accumulates diversity as a consequence of its geological history, its location on the junction between the two main tropical oceans and the presence of a land bridge during glacial times in the IMPA that fostered allopatric divergence and secondary contacts between the Indian and Pacific oceans
Worm Grunting, Fiddling, and Charming—Humans Unknowingly Mimic a Predator to Harvest Bait
Background: For generations many families in and around Florida’s Apalachicola National Forest have supported themselves by collecting the large endemic earthworms (Diplocardia mississippiensis). This is accomplished by vibrating a wooden stake driven into the soil, a practice called ‘‘worm grunting’’. In response to the vibrations, worms emerge to the surface where thousands can be gathered in a few hours. Why do these earthworms suddenly exit their burrows in response to vibrations, exposing themselves to predation? Principal Findings: Here it is shown that a population of eastern American moles (Scalopus aquaticus) inhabits the area where worms are collected and that earthworms have a pronounced escape response from moles consisting of rapidly exiting their burrows to flee across the soil surface. Recordings of vibrations generated by bait collectors and moles suggest that ‘‘worm grunters’ ’ unknowingly mimic digging moles. An alternative possibility, that worms interpret vibrations as rain and surface to avoid drowning is not supported. Conclusions: Previous investigations have revealed that both wood turtles and herring gulls vibrate the ground to elicit earthworm escapes, indicating that a range of predators may exploit the predator-prey relationship between earthworms and moles. In addition to revealing a novel escape response that may be widespread among soil fauna, the results sho
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