504 research outputs found
Nodular eruptions as a rare complication of botulinum neurotoxin type-A : case series and review of literature
Nodular eruption after botulinum neurotoxin type-A (BoNT-A) treatment is exceedingly rare, and the pathogenesis is poorly understood. This case series reports three patients that developed nodular eruptions following administration of Botox® (onabotulinum neurotoxin type A (ONA) injections). These patients had undergone multiple treatments before and after development of the eruptions which were uneventful. In addition to this, we have reviewed the published literature regarding this condition and have compared and contrasted the similarities and differences with regards to the clinical presentation and treatment with our patient cohort. This case series aims to raise awareness of this rare condition, its importance in relation to patient consent and provides a simplified management approach based on our experience. Further evaluation is needed to determine treatment consensus but conducting such research may prove to be challenging due to this condition being an infrequent encounter
Mouse hepatitis virus neurovirulence: evidence of a linkage between S glycoprotein expression and immunopathology.
Differences in disease outcome between the highly neurovirulent MHV-JHM and mildly neurovirulent MHV-A59 have been attributed to variations within the spike (S) glycoprotein. Previously, we found that MHV-JHM neurovirulence was marked by diminished expression of interferon-gamma (IFN-gamma) mRNA and a reduced presence of CD8 T cells in the CNS concomitant with heightened macrophage inflammatory protein (MIP)-1 transcript levels and greater macrophage infiltration relative to MHV-A59 infection. Here, the ability of the S and non-spike genes to regulate these immune responses was evaluated using chimeric viruses. Chimeric viruses WTR13 and S4R22 were made on MHV-A59 variant backgrounds and, respectively, contained the S gene of MHV-A59 and MHV-JHM. Unexpectedly, genes other than S appeared to modulate events critical to viral replication and survival. Unlike unresolving MHV-JHM infections, the clearance of WTR13 and S4R22 infections coincided with strong IFN-gamma transcription and an increase in the number of CD8 T cells infiltrating into the CNS. However, despite the absence of detectable viral titers, approximately 40% of S4R22-infected mice succumbed within 3 weeks, indicating that the enhanced mortality following S4R22 infection was not associated with high viral titers. Instead, similar to the MHV-JHM infection, reduced survival following S4R22 infection was observed in the presence of elevated MIP-1alpha and MIP-1beta mRNA accumulation and enhanced macrophage numbers within infected brains. These observations suggest that the S protein of MHV-JHM influences neurovirulence through the induction of MIP-1alpha- and MIP-1beta-driven macrophage immunopathology
Population characteristics of Shovelnose Sturgeon during low- and high-water conditions in the lower Platte River, Nebraska
Cycles of low- and high-water periods (i.e., years) in river systems are natural occurrences, but understanding how cyclical climatological patterns affect fishes, especially long-lived species, is unclear. We assessed Shovelnose Sturgeon population dynamics between a period of low- (2001-2004) and high- (2009-2012) water years in the lower Platte River, Nebraska. Low-flow periods in the lower Platte River can cause disconnection(s) between upstream and downstream reaches resulting in isolated pools and elevated water temperatures leading to stressful situations for aquatic life and possible mortality. Our data show no measurable differences between key population indices between flow condition periods which is consistent with current paradigms for long-lived fish species. Shovelnose Sturgeon relative weights were generally \u3e 80 during both low- and high-water periods and the size structure did not differ between the two periods. Shovelnose Sturgeon abundances, however, were greater during high-water conditions compared to low-water conditions (Kruskal-Wallis: χ2 = 6.15, d.f. = 1, P = 0.01). Shovelnose Sturgeon may have migrated to more suitable habitats during low-water periods to seek refuge allowing these individuals to return during more suitable conditions. Shovelnose Sturgeon and other riverine fish have evolved in a variable environment and have been able to endure relatively minor anthropogenic changes within the lower Platte River. Rivers like the lower Platte River that have retained much of their original physical features and flow regimes are likely key components for the resistance and resilience of riverine species. However, as alterations to landscapes continue and uncertainty exists surrounding future climate predictions, it is unknown how these riverine species will be able to adapt to future changes. The reduction in anthropogenic changes that disrupt flow regimes and increasing connectivity among river systems could provide more fish refuge during stressful conditions helping to protect these riverine species
The Weddelll Sea and Dronning Maud Land (WSDML) Regional Working Group Virtual Science Workshop, 20-23 October, 2020.
Workshop report from the Weddell Sea and Dronning Maud Land (WSDML) Regional Working Group virtual science workshop, held 20-23 October 2020
Novel roles for well-known players: from tobacco mosaic virus pests to enzymatically active assemblies
The rod-shaped nanoparticles of the widespread plant pathogen tobacco mosaic virus (TMV) have been a matter of intense debates and cutting-edge research for more than a hundred years. During the late 19th century, their behavior in filtration tests applied to the agent causing the \u27plant mosaic disease\u27 eventually led to the discrimination of viruses from bacteria. Thereafter, they promoted the development of biophysical cornerstone techniques such as electron microscopy and ultracentrifugation. Since the 1950s, the robust, helically arranged nucleoprotein complexes consisting of a single RNA and more than 2100 identical coat protein subunits have enabled molecular studies which have pioneered the understanding of viral replication and self-assembly, and elucidated major aspects of virus–host interplay, which can lead to agronomically relevant diseases. However, during the last decades, TMV has acquired a new reputation as a well-defined high-yield nanotemplate with multivalent protein surfaces, allowing for an ordered high-density presentation of multiple active molecules or synthetic compounds. Amino acid side chains exposed on the viral coat may be tailored genetically or biochemically to meet the demands for selective conjugation reactions, or to directly engineer novel functionality on TMV-derived nanosticks. The natural TMV size (length: 300 nm) in combination with functional ligands such as peptides, enzymes, dyes, drugs or inorganic materials is advantageous for applications ranging from biomedical imaging and therapy approaches over surface enlargement of battery electrodes to the immobilization of enzymes. TMV building blocks are also amenable to external control of in vitro assembly and re-organization into technically expedient new shapes or arrays, which bears a unique potential for the development of \u27smart\u27 functional 3D structures. Among those, materials designed for enzyme-based biodetection layouts, which are routinely applied, e.g., for monitoring blood sugar concentrations, might profit particularly from the presence of TMV rods: Their surfaces were recently shown to stabilize enzymatic activities upon repeated consecutive uses and over several weeks. This review gives the reader a ride through strikingly diverse achievements obtained with TMV-based particles, compares them to the progress with related viruses, and focuses on latest results revealing special advantages for enzyme-based biosensing formats, which might be of high interest for diagnostics employing \u27systems-on-a-chip\u27
Cube law, condition factor and weight-length relationships: history, meta-analysis and recommendations
This study presents a historical review, a meta-analysis, and recommendations for users about weight–length relationships, condition factors and relative weight equations. The historical review traces the developments of the respective concepts. The meta-analysis explores 3929 weight–length relationships of the type W = aLb for 1773 species of fishes. It shows that 82% of the variance in a plot of log a over b can be explained by allometric versus isometric growth patterns and by different body shapes of the respective species. Across species median b = 3.03 is significantly larger than 3.0, thus indicating a tendency towards slightly positive-allometric growth (increase in relative body thickness or plumpness) in most fishes. The expected range of 2.5 < b < 3.5 is confirmed. Mean estimates of b outside this range are often based on only one or two weight–length relationships per species. However, true cases of strong allometric growth do exist and three examples are given. Within species, a plot of log a vs b can be used to detect outliers in weight–length relationships. An equation to calculate mean condition factors from weight–length relationships is given as Kmean = 100aLb−3. Relative weight Wrm = 100W/(amLbm) can be used for comparing the condition of individuals across populations, where am is the geometric mean of a and bm is the mean of b across all available weight–length relationships for a given species. Twelve recommendations for proper use and presentation of weight–length relationships, condition factors and relative weight are given
Intrarectal transmission, systemic infection, and CD4+ T cell depletion in humanized mice infected with HIV-1
Intrarectal infection between men who have sex with men represents a predominant form of human immunodeficiency virus (HIV) transmission in developed countries. Currently there are no adequate small animal models that recapitulate intrarectal HIV transmission. Here we demonstrate that human lymphocytes generated in situ from hematopoietic stem cells reconstitute the gastrointestinal tract of humanized mice with human CD4+ T cells rendering them susceptible to intrarectal HIV transmission. HIV infection after a single intrarectal inoculation results in systemic infection with depletion of CD4+ T cells in gut-associated lymphoid tissue and other pathologic sequela that closely mimics those observed in HIV infected humans. This novel model provides the basis for the development and evaluation of novel approaches aimed at immune reconstitution of human gut-associated lymphoid tissue and for the development, testing, and implementation of microbicides to prevent intrarectal HIV-1 transmission
A single nucleotide substitution in TaHKT1;5-D controls shoot Na+ accumulation in bread wheat
Improving salinity tolerance in the most widely cultivated cereal, bread wheat (Triticum aestivum L.), is essential to increase grain yields on saline agricultural lands. A Portuguese landrace, Mocho de Espiga Branca accumulates up to sixfold greater leaf and sheath sodium (Na+) than two Australian cultivars, Gladius and Scout, under salt stress in hydroponics. Despite high leaf and sheath Na+ concentrations, Mocho de Espiga Branca maintained similar salinity tolerance compared to Gladius and Scout. A naturally occurring single nucleotide substitution was identified in the gene encoding a major Na+ transporter TaHKT1;5-D in Mocho de Espiga Branca, which resulted in a L190P amino acid residue variation. This variant prevents Mocho de Espiga Branca from retrieving Na+ from the root xylem leading to a high shoot Na+ concentration. The identification of the tissue-tolerant Mocho de Espiga Branca will accelerate the development of more elite salt-tolerant bread wheat cultivars
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