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An elderly gentleman self-presented to A+E with a 7-day history of significant and progressive left-sided neck pain, swelling and fevers, despite oral antibiotics from his general practitioner. Examination revealed a large left-sided neck mass involving levels 2-5 of the neck that was firm to palpate, with erythematous overlying skin.An urgent CT scan demonstrated a large collection throughout the length of the left sternocleidomastoid muscle (SCM), measuring 13×5.5×4 cm, with extensive adjacent inflammatory change. He was subsequently taken to theatre for washout and debridement, during which the collection was found to be loculated and isolated to the SCM, with surrounding structures spared.Postoperatively, he was managed with intravenous fluids and a total of 2 weeks of intravenous antibiotics. The wound partially dehisced during healing and the cavity was packed with flaminal and regularly dressed with input from the tissue viability team. This was then left to heal by secondary intention and the patient was followed up in clinic over the following weeks to ensure resolution., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Immunization of calves with Anaplasma centrale is used to prevent acute anaplasmosis caused by A. marginale . Natural and vaccine-acquired immunity is detected through serologic tests based primarily on A. marginale recombinant major surface protein 5 (MSP5m) because it has 91% identity with MSP5 from A. centrale (MSP5c). We developed a displacement, double-antigen, sandwich ELISA (ddasELISA) to detect antibodies against A. marginale or A. centrale. For ddasELISA validation, we analyzed serum samples positive for antibodies against Anaplasma spp. from cattle naturally infected with A. marginale ( n  = 300) or vaccinated with A. centrale ( n  = 255). Species-specific nested PCR (nPCR) assays were used to confirm infection. The optical density (OD) values obtained from antibodies directed at unique epitopes of A. marginale (OD Am ) or A. centrale (OD Ac ) were used in the formula OD Am /OD Ac . If the derived ratio was >0.38, the serum sample was considered positive for antibodies against A. marginale , with 98.9% sensitivity and 98.0% specificity. In a field evaluation, we analyzed 702 Anaplasma spp. antibody-positive serum samples from 34 herds by ddasELISA and nPCR; 571 were classified by ddasELISA as A. marginale -infected or A. centrale -vaccinated, with 84% agreement (κ = 0.70) between ddasELISA and nPCR. Our results indicate that ddasELISA could be used as a cost-effective alternative to molecular techniques to confirm infection with A. marginale in countries in which prevention is based on vaccination with A. centrale .

A nested polymerase chain reaction-restriction fragment length polymorphism (nPCR-RFLP) assay based on the amplification of the Anaplasma spp. highly conserved msp5 gene and posterior digestion with HindIII endonuclease was developed and evaluated in field samples. Results were compared using an nPCR specific for Anaplasma marginale (nPCR-Am) based on the msp1β gene and an nPCR specific for A. centrale (nPCR-Ac) based on the msp2 operon (msp2-o) gene. Amplicons dilutions of msp1β and msp5 of A. marginale and msp2-o and msp5 of A. centrale and dilutions of parasited erythrocytes (PE) with A. marginale and A. centrale were used to determine the detection limits. The results were 20 DNA copies/reaction and 30 PE for A. marginale and A. centrale by nPCR-RLFP and nPCR-Am/Ac. A mix of msp5-Am and msp5-Ac was used to evaluate the interference of msp5 from one species for the detection of the other. Co-amplification of the DNA from both species was observed up to a 1:7 ratio of one species to the other. Field samples positive for Anaplasma spp. antibodies (n = 260) from 32 herds were evaluated. Strength of agreement between results by nPCR-RFLP and nPCR-Am or nPCR-Ac was 78% (κ = 0.44) and 94% (κ = 0.85), respectively. Thirty-four samples were positive for A. marginale by nPCR-RFLP but negative by nPCR-Am. msp1β amplicons of 10 samples from 5 herds with discrepancies between nPCR-Am and nPCR-RFLP results were cloned and sequenced. The analysis of the msp1β sequence showed several mutations in the target region of the internal forward primer that would explain the failure in the amplification. Only 10 of the 20 coinfections identified by nPCR-Ac/nPCR-Am were detected by nPCR-RFLP. nPCR-RFLP is a sensitive, low-cost and accessible molecular method for low-complexity laboratories. More studies are needed to establish in which circumstances coinfections can be underestimated., (Copyright © 2022. Published by Elsevier GmbH.)

To investigate the presence of Theileria equi in an endemic area of equine piroplasmosis 42 horses (Equus caballus) from Corrientes City, Argentina were sampled. Eighty-one percent (34 blood samples) of the analyzed horses were tested positive to the presence of piroplasmid 18S rDNA. All these samples could be identified as T. equi by amplifying the specific EMA-1 (merozoite antigen 1) gene of this species. Phylogenetic analysis of an obtained 18S rDNA complete sequence from one strain resulted in the identification of this sample as T. equi sensu stricto (genotype A). This study presents the first molecular detection and characterization of T. equi by the complete 18S rDNA sequence in Argentina. Based on these results further studies should be carried out to investigate the distribution and heterogeneity of presented genotypes of T. equi in Argentina, which is essential for the diagnosis, prevention and treatment of equine piroplasmosis., (Copyright © 2021. Published by Elsevier GmbH.)

The aim of this study was to evaluate the influence of the long-acting oxytetracycline (OTC) treatment on A. marginale genotypes of the isolate S1P, by analyzing the msp1α genotype based on a microsatellite (ms) and tandem repeat sequences (TRS) located at the 5´ end of the gene. DNA samples were obtained from a longitudinal study of chemosterilization; 10 2-year-old steers were experimentally infected with blood from a splenectomized calf inoculated with the A. marginale isolate S1P. All the steers had received a first dose of 20 mg kg -1  OTC to treat acute disease, and once recovered all steers received a sterilizing treatment based on three doses of 20 mg kg -1  OTC 7 days apart. Blood from two steers not sterilized by the treatment was inoculated into two splenectomized calves (receptors) 104 days after treatment. DNA samples (S) used for msp1α amplification were obtained from i) the donor calf (S0), ii) 10 steers during acute disease (S1), after the first antibiotic treatment (S2), and after the chemosterilization procedure (S3 and S4), and iii) two receptor calves (S5). Thirty clones from the donor calf and at least 5 clones from the other DNA samples were analyzed. The genotype E/αββββГ msp1α identified in the donor calf and steers, before OTC treatment, was not detected either in steers that continued infected after the sterilizing treatment or in the receptor calves, in which only genotype C/EϕFF msp1α was observed. These results highlight the existence of A. marginale genotypes with different sensitivity to OTC and the importance of other variables to successfully sterilize the carriers., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

We describe the case of a 33-year-old female smoker who presented to the Accident and Emergency department with a 1-day history of rapidly evolving airway compromise. She had no preceding illness or other objective signs/symptoms on presentation, had a history of Chronic Obstructive Pulmonary Disease (COPD) and a previous opioid addiction. Following failed endotracheal intubation, the airway was secured with an emergency surgical tracheostomy. Subsequent direct laryngoscopy revealed a severely diseased glottis and supraglottic area, from which biopsy samples revealed a multiple drug-resistant strain of Candida albicans requiring specialist microbiology input and antifungal treatment. We describe the presentation, investigation, management and outcome of this rare case, along with a literature review of the subject., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Degeneration and death of motor neurons in Amyotrophic Lateral Sclerosis (ALS) are associated with increased lipid peroxidation. Lipid peroxidation is the driver of ferroptosis, an iron-dependent oxidative mode of cell death. However, the importance of ferroptosis in motor neuron degeneration of ALS remains unclear. Glutathione peroxidase 4 (Gpx4) is a key enzyme in suppressing ferroptosis by reducing phospholipid hydroperoxides in membranes. To assess the effect of increased protection against ferroptosis on motor neuron disease, we generated SOD1 G93A GPX4 double transgenic mice by cross-breeding GPX4 transgenic mice with SOD1 G93A mice, a widely used ALS mouse model. Compared with control SOD1 G93A mice, both male and female SOD1 G93A GPX4 mice had extended lifespans. SOD1 G93A GPX4 mice also showed delayed disease onset and increased motor function, which were correlated with ameliorated spinal motor neuron degeneration and reduced lipid peroxidation. Moreover, cell toxicity induced by SOD1 G93A was ameliorated by Gpx4 overexpression and by chemical inhibitors of ferroptosis in vitro. We further found that the anti-ferroptosis defense system in spinal cord tissues of symptomatic SOD1 G93A mice and sporadic ALS patients might be compromised due to deficiency of Gpx4. Thus, our results suggest that ferroptosis plays a key role in motor neuron degeneration of ALS.

Specimens of a Trypanosoma sp. were found in a haemolymph sample of Rhipicephalus microplus from Argentina. Polymerase chain reaction (PCR) was done targeting the SSU rRNA gene of Trypanosoma spp. and a fragment of 2300 base pairs (bp) was amplified, subsequently a phylogenetic analysis was conducted, based on an alignment of 905 bp, containing the sequence of the Argentina isolate and sequences of different Trypanosoma species retrieved from GenBank. Phylogenetic analysis revealed that this trypanosome is not related to Trypanosoma theileri as was previously thought, instead the strain of Trypanosoma detected in this study can be provisionally determined as belonging to the recently described organism Trypanosoma rhipicephalis. Furthermore, phylogenetic analysis performed in this work revealed that T. rhipicephalis belongs to a novel clade of tick-related trypanosomes, most with limited genetic data, for which essential aspects of both the vertebrate and invertebrate life cycles are lacking. The lack of basic information restricts the inferences that can be done from the present finding and, in addition, points out a clear knowledge gap in the biology of this group of trypanosomes., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Females, nymphs, and larvae of Ixodes silvanus n. sp. collected from birds and from the vegetation in northwestern Argentina (Yungas Phytogeographic Province) are described herein. The new species belongs to the subgenus Trichotoixodes (Acari: Ixodidae). The female is diagnosed by a combination of the following characters: scutum with setae moderately long and more numerous in central field, fewer and moderately long setae on lateral fields, and inconspicuous setae in anterior field; basis capituli subtriangular dorsally; porose areas large and irregular in shape, lacking distinct margins; auriculae with straight edges diverging posterolaterally and ending with small blunt processes; hypostome narrow and pointed with dental formula 4/4 in the anterior third, then 3/3 and 2/2 near the base; coxae I with two spurs, sub-equal in size, internal slightly slimmer than external. The nymph is diagnosed by notum with numerous and long setae, ventral surface covered by numerous whitish setae, scutum with short scapulae and few and shallow punctations, setae on scutum few, short and irregularly distributed, basis capituli sub-triangular dorsally with posterior margin straight, cornua large and directed postero-laterally, auriculae large and projected laterally, lateral margin of basis capituli above auriculae with a lateral and triangular projection, hypostome pointed with dental formula 3/3 in the anterior third and then 2/2, and coxa I with two short, sub-equal, triangular spurs. The diagnostic characters of the larva are: basis capituli dorsally sub-triangular with lateral angles acute and posterior margin straight, auriculae as large triangular lateral projections, hypostome with apex bluntly pointed and dental formula 3/3 in the anterior third and then 2/2, coxa I with two short, sub-equal, triangular spurs, and pattern of dorsal and ventral body setae. This new species is phylogenetically related to Ixodes brunneus, Ixodes turdus and Ixodes frontalis, and the principal hosts for all its parasitic stages are birds., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

An immunobiosensor assay was developed for multi-residue screening in bovine milk of the parent amphenicols, thiamphenicol and florfenicol, along with the metabolite florfenicol amine. A polyclonal antibody raised in a rabbit after immunisation with a florfenicol amine-protein conjugate was employed in the assay. Milk samples were subjected to acetonitrile extraction, reconstituted in buffer and diluted prior to biosensor analysis. Validation data obtained from the analysis of fortified samples has shown that the method has a detection capability of less than 0.25 µg kg -1 for florfenicol and less than 0.5 µg kg -1 for florfenicol amine and thiamphenicol. The cross-reactivity profile and validation data for the detection of these amphenicols is presented together with results obtained following the analysis of florfenicol incurred samples using the developed screening method along with a comparison of results obtained from the analysis of the same incurred samples using an MRM 3 UPLC-MS/MS confirmatory method. Results are also presented obtained from the analysis of samples from both treated and non-treated animals which were co-housed and which show the potential for cross-contamination.

We describe the case of a 12-year-old boy who reported unilateral hearing loss following laparoscopic appendicectomy for acute appendicitis under general anaesthesia. He was otherwise fit and well with no previous otological history. Formal audiological assessment by pure tone audiogram demonstrated a unilateral high-frequency sensorineural hearing loss (SNHL).In addition to describing his clinical course, a literature review of SNHL following non-otological surgery was performed. We recommend an awareness of this phenomenon, necessitating its prompt recognition, early audiological assessment and management as per sudden onset SNHL guidelines., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Characterization of photovoltaic (PV) module materials throughout different stages of service life is crucial to understanding and improving the durability of these materials. Currently the large-scale of PV modules (>1 m 2 ) is imbalanced with the small-scale of most materials characterization tools (≤1 cm 2 ). Furthermore, understanding degradation mechanisms often requires a combination of multiple characterization techniques. Here, we present adaptations of three standard materials characterization techniques to enable mapping characterization over moderate sample areas (≥25 cm 2 ). Contact angle, ellipsometry, and UV-vis spectroscopy are each adapted and demonstrated on two representative samples: a commercial multifunctional coating for PV glass and an oxide combinatorial sample library. Best practices are discussed for adapting characterization techniques for large-area mapping and combining mapping information from multiple techniques.

The goal of this study was to clarify the taxonomic status of the Ixodes ricinus complex in the Southern Cone of America, by using morphological characters and molecular markers (mitochondrial 16SrDNA and cox1 genes). The morphological analysis indicates that three different taxa of the I. ricinus complex occur in this region: Ixodes pararicinus, Ixodes aragaoi, and Ixodes sp. cf. I. affinis. The most prominent diagnostic character among them is the size of scutal punctations in both male and female ticks. In the males of Ixodes sp. cf. I. affinis, the punctations on the central field and along the median marginal groove of the scutum are clearly larger than in the males of I. aragaoi and I. pararicinus, while the punctations of I. aragaoi are larger but less numerous than in I. pararicinus. The punctations in Ixodes sp. cf. I. affinis females are larger and deeper than in females of I. aragaoi and I. pararicinus, and those of I. aragaoi are slightly larger than in I. pararicinus. The length of the lateral posterior denticles of the male hypostome is comparatively longer in I. aragaoi than in the other two species, and longer in Ixodes sp. cf. I. affinis than in I. pararicinus. In the 16S analysis, I. pararicinus and I. aragaoi are monophyletic (99% and 98% bootstrap support, respectively), while Ixodes cf. I. affinis does not represent a single lineage. In the cox1 analysis, both I. pararicinus and I. aragaoi are well-defined taxa, but the bootstrap support for Ixodes sp. cf. I. affinis is low (67%). In general, there are considerable 16SrRNA differences among lineages of Ixodes sp. cf. I. affinis from different geographical areas. These results may be indicative of the existence of different species. The populations morphologically compatible with I. affinis from Argentina, Colombia, Panama, Belize, and USA should be provisionally named as Ixodes sp. cf. I. affinis until an integrative taxonomic work with further evidence redefines whether or not this taxon actually represents a species complex.

Bovine anaplasmosis is a worldwide infectious disease caused by the intraerythrocytic bacterium Anaplasma marginale , which is transmitted by ticks and fomites. A. centrale is a less virulent subspecies used as a live vaccine in cohorts of 8- to 10-mo-old calves that did not naturally reach enzootic stability. We developed 3 variants of a double-antigen sandwich ELISA (dasELISA) using a recombinant major surface protein 5 (MSP5) from A. marginale (dasELISAm) or from A. centrale (dasELISAc) or using MSP5 from both organisms (dasELISAmc). Each dasELISA was tested for the detection of antibodies against A. marginale and A. centrale . The tests were validated using serum samples from cattle not infected with Anaplasma spp. ( n = 388), infected with A. marginale ( n = 436), and vaccinated with A. centrale ( n = 358), confirmed by nested PCR. A total of 462 samples were compared with a commercial competitive ELISA (cELISA). For dasELISAm, dasELISAc, and dasELISAmc, specificities were 98.7%, 98.7%, and 97.4%, and overall sensitivities were 92.6%, 85.7%, and 97.4%, respectively. For A. marginale -infected and A. centrale -vaccinated cattle, sensitivities were 97.7% and 86.3% for dasELISAm, and 77.7% and 95.5% for dasELISAc, respectively. Sensitivity of dasELISAmc was similar for both groups (>96%). The agreement rate between dasELISAmc and cELISA was 96.3% (κ = 0.92); the former test allowed earlier detection of seroconversion of vaccinated cattle than did cELISA. Based on these results, the test could be used to 1) determine the enzootic stability or instability of anaplasmosis in calves, 2) conduct epidemiologic studies, and 3) evaluate the immunogenicity of A. centrale live vaccine.

A 27-year-old elite-level professional cyclist presented to the emergency department with a 6-hour history of chest pain and vomiting after prematurely aborting a competitive event. ECG demonstrated anterior ST segment elevation myocardial infarction, and blood tests revealed a grossly elevated high-sensitivity troponin T. Emergent coronary angiography confirmed the presence of a thrombus in the mid-left anterior descending artery with possible spontaneous coronary artery dissection. The patient recovered well following balloon angioplasty and thrombus aspiration, despite delayed recognition, invasive investigation and intervention., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

The presence of Borrelia theileri in Argentina is confirmed after recording the spirochete from a bovine in northern Argentina. The analysis of sequences of the flagellin gene (fla) and length of Borrelia spp. specimens on thick blood films shows that the local isolate clusters within a well-supported clade with B. theileri isolates from different geographical origins, confirming the presence of B. theileri in Argentina. The mean length of 30 specimens of B. theileri was 12.89 μm (standard deviation 2.88 μm, range 9.35-20.16 μm). The only known vector of Borrelia theileri in northern Argentina is the cattle tick Rhipicephalus microplus, therefore Borrelia infection should be regarded as a potential complication of other cattle tick-borne diseases such as babesiosis, especially on cattle introduced from areas free of R. microplus. The possibility of serologic cross-reaction with B. theileri must not be minimized in studies of other spirochaetes in the R. microplus infested region of Argentina., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objectives: To compare soleus spinal reflex excitability, presynaptic inhibition and recurrent inhibition between chronic ankle instability (CAI), acute Lateral Ankle Sprain coper (LAS-coper) and healthy populations. The relationship between spinal reflex excitability and pain and perceived instability in people with CAI was also examined., Design: Cross-sectional laboratory experiment., Methods: Twelve individuals with CAI, twelve 'copers' and twelve healthy age, limb and gender-matched controls participated. Soleus H-reflex recruitment curves, pre-synaptic excitability and recurrent inhibition of the spinal-reflex pathway were examined during static double- and single-leg stance. Reporting of pain and perceived instability were used to perform a regression analysis on measures of soleus spinal excitability in people with CAI, LAS-coper and healthy controls., Results: Soleus spinal reflex excitability was greater during single-leg stance in CAI compared to healthy and coper individuals (p=<0.001). Pre-synaptic inhibition was three-times less in CAI participants compared to both healthy controls and copers (p=<0.001). There were no differences between healthy and coper participants in spinal-level measures of sensorimotor control. Reports of pain explained 15-16% of the variance in soleus spinal reflex excitability and presynaptic inhibition during single and double-leg stance, while perceived instability explained 20% of the variance in spinal reflex during single leg stance only., Conclusions: CAI participants presented with an inability to suppress soleus spinal reflexes during tasks with increased postural threat; likely due to disinhibition of pre-synaptic mechanisms. Pain and perceived instability may contribute to changes in spinal-level sensorimotor control in CAI., (Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.)

Background : Long-term potentiation (LTP) is recognised as a core neuronal process underlying long-term memory. However, a direct relationship between LTP and human memory performance is yet to be demonstrated. The first aim of the current study was thus to assess the relationship between LTP and human long-term memory performance. With this also comes an opportunity to explore factors thought to mediate the relationship between LTP and long-term memory. The second aim of the current study was to explore the relationship between LTP and memory in groups differing with respect to brain-derived neurotrophic factor (BDNF) Val 66 Met; a single-nucleotide polymorphism (SNP) implicated in memory function. Methods : Participants were split into three genotype groups (Val/Val, Val/Met, Met/Met) and were presented with both an EEG paradigm for inducing LTP- like enhancements of the visually-evoked response, and a test of visual memory. Results : The magnitude of LTP 40 min after induction was predictive of long-term memory performance. Additionally, the BDNF Met allele was associated with both reduced LTP and reduced memory performance. Conclusions : The current study not only presents the first evidence for a relationship between sensory LTP and human memory performance, but also demonstrates how targeting this relationship can provide insight into factors implicated in variation in human memory performance. It is anticipated that this will be of utility to future clinical studies of disrupted memory function.

Detection of antibodies to Anaplasma spp. using commercial competitive enzyme-linked immunosorbent assay (ccELISA) is based on the recombinant major surface protein 5 fused to maltose binding protein (MBP-MSP5) or glutathione S-transferase (GST-MSP5). To avoid false positive reactions due to the presence of antibodies against E. coli MBP in cattle, previous sera absorption is required. This study evaluated the replacement of MBP-MSP5 or GST-MSP5 antigens by the truncate MSP5 (residues 28-210) of A. marginale (tMSP5m), A. centrale (tMSP5c) and fusion protein MSP5 (tMSP5cm), expressed without N-terminus transmembrane helix in the ccELISA test. Immunoreactivity was evaluated by western blot using monoclonal antibodies against the tMSP5 and by in-house cELISA (hcELISA) with purified tMSP5m, tMSP5c or tMSP5cm using sera from cattle infected with A. marginale (n = 226) or vaccinated with A. centrale (n = 173) and uninfected cattle (n = 216). Results of hcELISA were compared with those of ccELISA. Recombinant protein was expressed highly soluble (> 95%) in E. coli without a molecular chaperone. Specificity of the hcELISA-tMSP5m, -MSP5c or -tMSP5cm was identical to (99.5%) and greater than that in ccELISA (96.3%). Sensitivity of hcELISA-tMSP5m and ccELISA was identical (95.5%), but lower than that of hcELISA-tMSP5cm (96.2%) and -tMSP5c (97.2%). The analysis of vaccinated cattle by hcELISA-tMSP5c showed sensitivity of 99.4%. In summary, the generation of fusion MSP5 A. marginale-A. centrale protein without transmembrane helix was a very effective method to express the recombinant protein highly soluble in the bacterial cytoplasm and contributed to an increased test performance for detecting antibodies in cattle naturally infected with A. marginale or vaccinated with A. centrale., Competing Interests: The authors have declared that no competing interests exist.

A 30-year-old woman presented to the accident and emergency department 3 days post-tonsillectomy with bleeding from the tonsillar fossa and left-sided facial swelling. The patient denied any dysphagia or breathing difficulties but experienced pain on neck movement. On examination, although the bleeding had stopped on reaching the emergency department, a small clot was noted in her left tonsillar fossa. A left facial/submandibular swelling was seen, which had been present since her operation and was slowly enlarging. Flexible nasendoscopy showed a mild left sided oropharyngeal swelling but was otherwise normal. She was treated initially with antibiotics and hydrogen peroxide gargles. After 24 hours of observation and a slight worsening of the swelling she underwent a CT of the neck. This showed widespread indurated subcutaneous surgical emphysema, originating from the left tonsillar bed. Following a period of observation and improvement in her symptoms, she was discharged home with safety netting., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Tau protein accumulation is the most common pathology among degenerative brain diseases, including Alzheimer's disease (AD), progressive supranuclear palsy (PSP), traumatic brain injury (TBI), and over twenty others. Tau-containing neurofibrillary tangle (NFT) accumulation is the closest correlate with cognitive decline and cell loss (Arriagada, Growdon, Hedley-Whyte, & Hyman, ), yet mechanisms mediating tau toxicity are poorly understood. NFT formation does not induce apoptosis (de Calignon, Spires-Jones, Pitstick, Carlson, & Hyman, 2009), which suggests that secondary mechanisms are driving toxicity. Transcriptomic analyses of NFT-containing neurons microdissected from postmortem AD brain revealed an expression profile consistent with cellular senescence. This complex stress response induces aberrant cell cycle activity, adaptations to maintain survival, cellular remodeling, and metabolic dysfunction. Using four AD transgenic mouse models, we found that NFTs, but not Aβ plaques, display a senescence-like phenotype. Cdkn2a transcript level, a hallmark measure of senescence, directly correlated with brain atrophy and NFT burden in mice. This relationship extended to postmortem brain tissue from humans with PSP to indicate a phenomenon common to tau toxicity. Tau transgenic mice with late-stage pathology were treated with senolytics to remove senescent cells. Despite the advanced age and disease progression, MRI brain imaging and histopathological analyses indicated a reduction in total NFT density, neuron loss, and ventricular enlargement. Collectively, these findings indicate a strong association between the presence of NFTs and cellular senescence in the brain, which contributes to neurodegeneration. Given the prevalence of tau protein deposition among neurodegenerative diseases, these findings have broad implications for understanding, and potentially treating, dozens of brain diseases., (© 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

The crab-eating raccoon (Procyon cancrivorus) is a carnivore widely distributed from southern Central America to all South American countries except Chile. In the Southern cone of America, P. cancrivorus has been found parasitized by several Amblyomma spp. Particularly, in Uruguay, A. aureolatum is the only tick found in this wild carnivore. Piroplasmid hemoparasites were found in Procyon lotor from North America and Japan. In this work, molecular evidence Babesia sp. DNA was found in blood and tissues from road-killed P. cancrivorus from different locations in Uruguay. PCRs targeting 18S rRNA gene were carried out. Subsequently, the obtained amplicons were sequenced and full-length sequences was assembled. A phylogenetic tree was constructed and revealed that the Babesia sp. found in this work clustered with other 18sRNA sequences of Babesia spp. obtained from P. lotor from Japan and USA, along with Babesia spp. of maned wolf and I. ovatus. This is the first report of molecular evidence of Babesia sp. parasitizing P. cancrivorus., (Copyright © 2018. Published by Elsevier B.V.)

The molecular basis for ultraviolet (UV) light-induced nonmelanoma and melanoma skin cancers centers on cumulative genomic instability caused by inefficient DNA repair of dipyrimidine photoproducts. Inefficient DNA repair and subsequent translesion replication past these DNA lesions generate distinct molecular signatures of tandem CC to TT and C to T transitions at dipyrimidine sites. Since previous efforts to develop experimental strategies to enhance the repair capacity of basal keratinocytes have been limited, we have engineered the N-terminally truncated form (Δ228) UV endonuclease (UVDE) from Schizosaccharomyces pombe to include a TAT cell-penetrating peptide sequence with or without a nuclear localization signal (NLS): UVDE-TAT and UVDE-NLS-TAT. Further, a NLS was engineered onto a pyrimidine dimer glycosylase from Paramecium bursaria chlorella virus-1 (cv-pdg-NLS). Purified enzymes were encapsulated into liposomes and topically delivered to the dorsal surface of SKH1 hairless mice in a UVB-induced carcinogenesis study. Total tumor burden was significantly reduced in mice receiving either UVDE-TAT or UVDE-NLS-TAT versus control empty liposomes and time to death was significantly reduced with the UVDE-NLS-TAT. These data suggest that efficient delivery of exogenous enzymes for the initiation of repair of UVB-induced DNA damage may protect from UVB induction of squamous and basal cell carcinomas.

An immunobiosensor assay was developed for the multi-residue screening of the parent amphenicols, thiamphenicol and florfenicol, along with the metabolite florfenicol amine, in bovine, ovine and porcine kidney. A polyclonal antiserum raised in a rabbit after inoculation with a florfenicol amine-protein conjugate was employed in the assay. Sample homogenates were extracted directly into acetonitrile, reconstituted in buffer and diluted prior to biosensor analysis. Validation data obtained from the analysis of fortified samples has shown that the method has a detection capability (CCβ) of less than 25µgkg -1 (1/2 MRL) for thiamphenicol in the kidney of all three species, less than 150µgkg -1 (1/2 MRL) for florfenicol and florfenicol amine and less than 250µgkg -1 (1/2 MRL) for florfenicol and florfenicol amine in bovine/ovine and porcine kidney respectively. Intra-assay variation (n=10) was calculated at 4.5% and 2.6% at concentrations of 10µgkg -1 and 150µgkg -1 respectively for bovine kidney while inter-assay variation (n=3) was determined to be 5.0% and 16.5% respectively at the same concentrations. The cross-reactivity profile and validation data for the detection of these amphenicols is presented together with the results obtained following the analysis of florfenicol incurred samples using the developed method., (Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.)

Cerebral small vessel disease (CSVD) is a pathological process leading to lacunar infarcts, leukoaraiosis and cerebral microbleeds. Dysfunction of the blood brain barrier (BBB) has been proposed as a mechanism in the progression cerebral small vessel disease. A rodent model commonly used to study some aspects of CSVD is bilateral common carotid artery occlusion (BCCAO) in the rat. In the present study it was determined that gait impairment, as determined by a tapered beam test, and BBB permeability increased following BCCAO. Cilostazol, a type III phosphodiesterase inhibitor, has been shown to have anti-apoptotic effects and prevent white matter vacuolation and rarefaction induced by BCCAO in rats. In this study the protective effect of cilostazol administration on the increase BBB permeability following BCCAO was determined as well as the effect on plasma levels of circulating microparticles (MPs), cerebral white matter rarefaction, glial activation and gait disturbance. The effect of cilostazol on in vitro endothelial barriers was also evaluated. Cilostazol treatment improved BBB permeability and reduced gait disturbance, visual impairment and microglial activation in optic tract following BCCAO in vivo. It also reduced the degree of cell death and the reduction in trans-endothelial electrical resistance (TEER) in artificial endothelial barriers in vitro induced by MP treatment of in vitro barriers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Impaired spinal-level neuromuscular control is suggested to contribute to instability and injury during dynamic landing tasks. Despite this suggestion, spinal-level neuromuscular control is yet to be examined during a horizontal jump-landing task. The aim of the current study was to assess changes in H-reflexes and its reliability at the short-latency response of landings from short and long distances. Eight healthy individuals (five male, three female; age, 22±1.2yrs; height, 178±8.1cm; weight, 72±15.7kg) participated in the study. H-reflexes were evoked at the SLR in the soleus and medial gastrocnemius muscles, during two landing conditions: 25% and 50% of maximal broad jump distance. H-reflexes were expressed relative to the background electromyography (EMG) and maximal M-wave responses (M-max). Soleus H-reflexes were inhibited when landing from shorter distance (25%, 13.9±7.6%; 50%, 8.3±6.5%; p<0.01). No change in H-reflex excitability was observed in medial gastrocnemius. Background EMG was unaltered across landing conditions. Inhibition of soleus H-reflex excitability from 25% to 50% landing condition indicates a reduced contribution of Ia-afferent feedback to the alpha-motor neuron during landings from greater distances, which may contribute to stiffness regulation at the ankle joint. Unaltered H-reflex excitability of medial gastrocnemius is most likely attributed to its functional role during the landing task., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Numbers of circulating microparticles (MPs) are elevated in a variety of cardiovascular disorders, and recent studies indicate that they are involved in inflammatory intercellular signaling. In the present study the signaling properties of MPs were assessed in an in vitro model of the blood brain barrier. MPs isolated from the plasma of rats exposed to chronic cerebral ischemia caused a significant reduction in the transendothelial electrical resistance (TEER) when applied to in vitro endothelial barriers, while MPs isolated from an equal volume of plasma from unoperated or sham operated rats did not. The reduction in TEER was attenuated by treating endothelial barriers prior to exposure to MPs with the caspase 3 inhibitor AC-DEVD-CHO, the TNF-α inhibitor SPD304, the tumor necrosis factor alpha-converting enzyme (TACE, ADAM 17) inhibitor TAPI-0-1 and the Rho kinase (ROCK) inhibitor Y-27632, and by treating the MPs themselves with these inhibitors prior to applying them to cultured cells. This observation indicates that MPs generated during cerebral ischemia contain pro-TNF-α, active TACE and active ROCK. ROCK and Ras homolog gene family member A (RhoA) were detected in MPs by western blot. The growth factor VEGF stimulated transcellular transport in endothelial barriers while exposure to MPs did not. We conclude that the increase in permeability of artificial barriers induced by MPs is primarily due to enhanced apoptosis induced by activation of the TNF-α pathway and activated caspase 3 and Rho kinases delivered to endothelial cells by MPs., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A growing body of literature has explored the influence of physical activity on brain structure and function. While the mechanisms of this relationship remain largely speculative, recent research suggests that one of the effects of physical exercise is an increase in synaptic long-term potentiation (LTP). This has not yet been explored directly in humans due to the difficulty of measuring LTP non-invasively. However, we have previously established that LTP-like changes in visual-evoked potentials (VEPs) can be measured in humans. Here, we investigated whether physical fitness status affects the degree of visual sensory LTP. Using a self-report measure of physical activity, participants were split into two groups: a high-activity group, and a low-activity group. LTP was measured and compared between the two groups using the previously established electroencephalography-LTP paradigm, which assesses the degree to which the N1b component of the VEP elicited by a sine grating is potentiated (enhanced) following a rapid "tetanic" presentation of that grating. Both groups demonstrated increased negativity in the amplitude of the N1b component of the VEP immediately after presentation of the visual "tetanus," indicating potentiation. However, after a 30-min rest period, the N1b for the high-activity group remained potentiated while the N1b for the low-activity group returned to baseline. This study presents the first evidence for the impact of self-reported levels of physical activity on LTP in humans, and sheds light on potential neurological mechanisms underlying the relationship between physical fitness and cognition.

Single nucleotide polymorphisms in the brain-derived neurotrophic factor (BDNF) gene and the catechol-O-methyltransferase (COMT) gene influence brain structure and function, as well as cognitive abilities. They are most influential in the hippocampus and prefrontal cortex (PFC), respectively. Recall and recognition are forms of memory proposed to have different neural substrates, with recall having a greater dependence on the PFC and hippocampus. This study aimed to determine whether the BDNF val(66)met or COMT val(158)met polymorphisms differentially affect recall and recognition, and whether these polymorphisms interact. A sample of 100 healthy adults was assessed on recall and familiarity-based recognition using the Faces and Family Pictures subscales of the Wechsler Memory Scale - Third Edition (WMS-III). COMT genotype did not affect performance on either task. The BDNF polymorphism (i.e., met carriers relative to val homozygotes) was associated with poorer recall ability, while not influencing recognition. Combining subscale scores in memory tests such as the WMS might obscure gene effects. Our results demonstrate the importance of distinguishing between recall and familiarity-based recognition in neurogenetics research.

Some people have much better memory than others, and there is compelling evidence that a considerable proportion of this variation in memory ability is genetically inherited. A form of synaptic plasticity known as long-term potentiation (LTP) is the principal candidate mechanism underlying memory formation in neural circuits, and it might be expected, therefore, that a genetic influence on the degree of LTP might in turn influence memory abilities. Of the genetic variations thought to significantly influence mnemonic ability in humans, the most likely to have its effect via LTP is a single nucleotide polymorphism affecting brain-derived neurotrophic factor [BDNF (Val66Met)]. However, although it is likely that BDNF influences memory via a modulation of acute plasticity (i.e., LTP), BDNF also has considerable influence on structural development of neural systems. Thus, the influence of BDNF (Val66Met) on mnemonic performance via influences of brain structure as well as function must also be considered. In this brief review, we will describe the phenomenon of LTP and its study in non-human animals. We will discuss the relatively recent attempts to translate this work to studies in humans. We will describe how this has enabled investigation of the effect of the BDNF polymorphism on LTP, on brain structure, and on memory performance., (© 2014 John Wiley & Sons, Ltd.)

Elevated reactive oxygen species (ROS) are linked to insulin resistance and islet dysfunction. Manganese superoxide dismutase (SOD2) is a primary defense against mitochondrial oxidative stress. To test the hypothesis that heterozygous SOD2 deletion impairs glucose-stimulated insulin secretion (GSIS) and insulin action, wild-type (sod2(+/+)) and heterozygous knockout mice (sod2(+/-)) were fed a chow or high-fat (HF) diet, which accelerates ROS production. Hyperglycemic (HG) and hyperinsulinemic-euglycemic (HI) clamps were performed to assess GSIS and insulin action in vivo. GSIS during HG clamps was equal in chow-fed sod2(+/-) and sod2(+/+) but was markedly decreased in HF-fed sod2(+/-). Remarkably, this impairment was not paralleled by reduced HG glucose infusion rate (GIR). Decreased GSIS in HF-fed sod2(+/-) was associated with increased ROS, such as superoxide ion. Surprisingly, insulin action determined by HI clamps did not differ between sod2(+/-) and sod2(+/+) of either diet. Since insulin action was unaffected, we hypothesized that the unchanged HG GIR in HF-fed sod2(+/-) was due to increased glucose effectiveness. Increased GLUT-1, hexokinase II, and phospho-AMPK protein in muscle of HF-fed sod2(+/-) support this hypothesis. We conclude that heterozygous SOD2 deletion in mice, a model that mimics SOD2 changes observed in diabetic humans, impairs GSIS in HF-fed mice without affecting insulin action., (© 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

This paper addresses the identification, cloning, expression, purification and functional characterization of thioredoxin reductase from Babesia bovis, the etiological agent of babesiosis. The work deals with in vitro steady state kinetic studies and other complementary analyses of the thioredoxin reductase found in the pathogenic protist. Thioredoxin reductase from B. bovis was characterized as a homodimeric flavoprotein that catalyzes the NADPH-dependent reduction of Trx with a high catalytic efficiency. Moreover, the enzyme exhibited a disulfide reductase activity using DTNB as substrate, being this activity highly sensitive to inhibition by Eosin B. The thioredoxin reductase/thioredoxin system can reduce oxidized glutathione and S-nitrosoglutathione. Our in vitro data suggest that antioxidant defense in B. bovis could be supported by this enzyme. We have performed an enzymatic characterization, searching for targets for rational design of inhibitors. This work contributes to the better understanding of the redox biochemistry occurring in the parasite., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Pancreatic islets are highly vascularized mini-organs, and vascular endothelial growth factor (VEGF)-A is a critical factor in the development of islet vascularization. To investigate the role of VEGF-A and endothelial cells (ECs) in adult islets, we used complementary genetic approaches to temporally inactivate VEGF-A in developing mouse pancreatic and islet progenitor cells or in adult β-cells. Inactivation of VEGF-A early in development dramatically reduced pancreatic and islet vascularization, leading to reduced β-cell proliferation in both developing and adult islets and, ultimately, reduced β-cell mass and impaired glucose clearance. When VEGF-A was inactivated in adult β-cells, islet vascularization was reduced twofold. Surprisingly, even after 3 months of reduced islet vascularization, islet architecture and β-cell gene expression, mass, and function were preserved with only a minimal abnormality in glucose clearance. These data show that normal pancreatic VEGF-A expression is critical for the recruitment of ECs and the subsequent stimulation of endocrine cell proliferation during islet development. In contrast, although VEGF-A is required for maintaining the specialized vasculature observed in normal adult islets, adult β-cells can adapt and survive long-term reductions in islet vascularity. These results indicate that VEGF-A and islet vascularization have a lesser role in adult islet function and β-cell mass.

The importance of nitric oxide (NO) in vascular physiology is irrefutable; it stimulates the intracellular production of cyclic guanosine monophosphate (cGMP), initiating vascular smooth muscle relaxation. This biochemical process increases the diameter of small arteries, regulating blood flow distribution between arterioles and the microvasculature. The kidney is no exception, since NO predominantly dilates the glomerular afferent arterioles. It is now evident that the vascular production of cGMP can be augmented by inhibitors of phosphodiesterase type 5 (PDE 5), the enzyme which breakdowns this cyclic nucleotide. This has clinical relevance, since diabetic nephropathy (DN) a major microvascular complication of diabetes mellitus and the most common cause of end-stage renal disease, increases intraglomerular capillary pressure, leading to glomerular hypertension. PDE 5 inhibitors may have, therefore, the potential to reduce glomerular hypertension. This review describes the use of PDE 5 inhibitors to improve the metabolic, haemodynamic and inflammatory pathways/responses, all of which are dysfunctional in DN.

Introduction: We investigated the effect angiotensin II (Ang II), a corpus cavernosal smooth muscle (CCSM) constrictor peptide, has on tissue taken from rabbits following chronic partial bladder outlet obstruction (PBOO), as this model is characterized by an increase in corpus cavernosal collagen deposition and a marked reduction and impaired relaxation of CCSM cells., Aim: To determine the interaction between Ang II and nitric oxide (NO) and the development of oxidative stress (OS) in a rabbit model of chronic PBOO., Methods: Corpus cavernosal tissue was obtained from 12 sham-operated and 20 PBOO rabbits. Organ bath studies determined Ang II/NO interaction on CCSM function using losartan (AT1 receptor antagonist), sodium nitroprusside (SNP, NO donor), electrical field stimulation (EFS), and vardenafil (phosphodiesterase type 5 inhibitor). The role of OS in the Ang II response was also determined using diphenylene iodonium chloride (DPI), the nicotinamide adenine dinucleotide phosphate oxidase inhibitor, which inhibits superoxide production and superoxide dismutase (SOD, the enzyme that accelerates the breakdown of superoxide)., Main Outcome Measure: Action of Ang II and AT1 receptor antagonist, as well as SOD and DPI on CCSM function., Results: Ang II caused a dose-dependent contraction of CCSM strips that was enhanced in PBOO rabbits and inhibited by losartan, DPI, and SOD. CCSM relaxation induced by SNP/EFS was impaired in this model and improved by vardenafil and losartan., Conclusions: These findings imply that the increased Ang II contractile response is a pathological consequence of PBOO and that AT1 receptor inhibition may be a therapeutic approach to treat ED associated with PBOO., (© 2012 International Society for Sexual Medicine.)

Membrane microparticles are submicron fragments of membrane shed into extracellular space from cells under conditions of stress/injury. They may be distinguished from other classes of extracellular vesicles (i.e. exosomes) on the basis of size, content and mechanism of formation. Microparticles are found in plasma and other biological fluids from healthy individuals and their levels are altered in various diseases, including diabetes, chronic kidney disease, pre-eclampsia and hypertension among others. Accordingly, they have been considered biomarkers of vascular injury and pro-thrombotic or pro-inflammatory conditions. In addition to this, emerging evidence suggests that microparticles are not simply a consequence of disease, but that they themselves may contribute to pathological processes. Thus microparticles appear to serve as both markers and mediators of pathology. The present review examines the evidence for microparticles as both biomarkers of, and contributors to, the progression of disease. Approaches for the detection of microparticles are summarized and novel concepts relating to the formation of microparticles and their biological effects are examined.

We present a simple and inexpensive technique for bonding PDMS microfluidic devices. The technique uses only adhesive tape and an oven; plasma bonders and cleanroom facilities are not required. It also produces channels that are immediately hydrophobic, allowing formation of aqueous-in-oil emulsions.

Nitroxynil is an anthelmintic drug mainly used for the control of liver fluke in sheep and cattle. The European Commission has established maximum residue limits in bovine and ovine muscle (400 µg kg(-1)), fat (200 µg kg(-1)), liver (20 µg kg(-1)) and kidney (400 µg kg(-1)), and more recently in bovine and ovine milk (20 µg kg(-1)). To ensure that these limits are not exceeded through incorrect use of the drug, it is necessary to monitor samples using robust and reliable methods capable of low-level detection. An inexpensive and rapid immunobiosensor-based screening procedure, capable of high sample throughput, was developed that is capable of detecting nitroxynil at <10 µg kg(-1) in bovine milk, at <10 µg kg(-1) in bovine liver, and at <200 µg kg(-1) in bovine and ovine muscle. The methods were fully validated and the milk assay was utilised in a comparison study of nitroxynil-incurred samples.

Imidocarb (IMD) is a veterinary drug that has been used for more than 30 years to treat and prevent parasitic diseases. Pharmacokinetic studies have shown that substantial levels of IMD residues are retained in the edible tissues and milk of cattle and sheep for up to 6 months after administration. This has led to concern regarding the potential adverse effects posed through human consumption of edible tissue or milk from treated animals if the recommended withdrawal periods for the drug are not properly implemented. While MRLs have been established by the European Union, it is important that analytical methods are available to monitor food samples for potentially violative levels of IMD residues. A qualitative biosensor-based immunoassay was developed to allow the detection of IMD at less than the European Union MRLs of 50 μg kg(-1) for milk and 2 mg kg(-1) for bovine and ovine liver. Validation of the developed methods provided a detection capability of <25 μg kg(-1) in milk and <0.75 mg kg(-1) in liver. A comparison study was undertaken, with IMD incurred milk and ovine liver samples analysed by the newly developed procedures and results compared with those obtained by LC-MS/MS. The newly developed screening method was applied to both incurred milk and liver samples. This faster, cheaper and reliable screening method has potential use in sample analysis to ensure compliance with legislative requirements.

Background: Chronic disease accelerates endothelial dysfunction in aging, a process associated with cell senescence. However, the mechanisms underlying this process are unclear. We examined whether endothelial cell (EC)-derived microparticles (MPs) facilitate EC senescence and questioned the role of reactive oxygen species in this process., Methods and Results: Senescence was induced by sequential passaging of primary mouse ECs. Cells retained phenotypic characteristics of ECs from passage 4 through passage 21. Passage 21 ECs exhibited features of senescence, including increased staining of senescence-associated β-galactosidase (SA-βgal), a greater percentage of cells in G(1)/G(0) phase of the cell cycle, and increased phosphorylation of p66(Shc) (P<0.05). Microparticle formation from passage 21 ECs was increased versus passage 4 ECs (∼2.2-fold increase versus passage 4, P<0.05), and the Rho kinase inhibitor fasudil blocked this increase. Exposure of passage 4 ECs to MPs shifted cells from a proliferating to a nonproliferating phenotype, as indicated by cell cycle analysis and increased senescence-associated β-galactosidase staining. MPs increased EC generation of O(2) (•-) (∼2.7-fold) and H(2)O(2) (∼2.6-fold), effects blocked by apocynin (nicotinamide adenine dinucleotide phosphate oxidase inhibitor) and rotenone (mitochondrial oxidase inhibitor) but not by allopurinol (xanthine oxidase inhibitor). MPs increased expression of cell cycle proteins p 21 cip1 and p16ink4a and stimulated phosphorylation of p66(Shc) in ECs (P<0.05 versus untreated ECs). Pretreatment with the reactive oxygen species scavenger sodium 4,5-dihydroxybenzene-1,3-disulfonate (tiron) abrogated the prosenescent effects of MPs., Conclusions: MPs promote EC senescence through nicotinamide adenine dinucleotide phosphate oxidase- and mitochondrial-derived reactive oxygen species. Such redox-sensitive processes may be important in vascular dysfunction in aging. (J Am Heart Assoc. 2012;1:e001842 doi: 10.1161/JAHA.112.001842.).

There is a paucity of data regarding the safety of administering solid gold nanoparticles (AuNPs) in large animal tumor models. We assessed the acute toxicity and biodistribution of 5 nm and 25 nm solid AuNPs in New Zealand White rabbits (n = 6 in each) with implanted liver Vx2 tumors 24 h after intravenous injection. Gold concentration was determined by inductively coupled plasma atomic emission spectrometry (ICP) and imaged with transmission electron microscopy (TEM). There was no clinico-pathologic evidence of renal, hepatic, pulmonary, or other organ dysfunction. After 25 nm AuNP administration, the concentration of white blood cells increased after treatment (p = 0.001). Most other blood studies were unchanged. AuNPs were distributed to the spleen, liver, and Vx2 tumors, but not to other tissues. The urinary excretion of AuNPs was bimodal as measured by ICP. 25 nm AuNPs were more evenly distributed throughout tissues and may be better tools for medical therapy.