Direct bone marrow (BM) injection has been proposed as a strategy to bypass homing inefficiencies associated with intravenous (IV) hematopoietic stem cell (HSC) transplantation. Despite physical ...delivery into the BM cavity, many donor cells are rapidly redistributed by vascular perfusion, perhaps compromising efficacy. Anchoring donor cells to 3-dimensional (3D) multicellular spheroids, formed from mesenchymal stem/stromal cells (MSC) might improve direct BM transplantation. To test this hypothesis, relevant combinations of human umbilical cord blood-derived CD34(+) cells and BM-derived MSC were transplanted into NOD/SCID gamma (NSG) mice using either IV or intrafemoral (IF) routes. IF transplantation resulted in higher human CD45(+) and CD34(+) cell engraftment within injected femurs relative to distal femurs regardless of cell combination, but did not improve overall CD45(+) engraftment at 8 weeks. Analysis within individual mice revealed that despite engraftment reaching near saturation within the injected femur, engraftment at distal hematopoietic sites including peripheral blood, spleen and non-injected femur, could be poor. Our data suggest that the retention of human HSC within the BM following direct BM injection enhances local chimerism at the expense of systemic chimerism in this xenogeneic model.
Neuro-ophthalmologists have expertise in rare and complex disorders, but the ability of patients to access neuro-ophthalmic care has not been examined at a nationwide level.
Using the 2020 directory ...of all 502 members of the North American Neuro-Ophthalmology Society as a reference, we found the practice locations of 461 confirmed practicing members and converted each street address to latitude and longitude coordinates. We calculated the travel distance and time from each census tract to the nearest practice location and calculated population-weighted averages by state, region, and other prespecified factors. Choropleth maps were used to visualize the distribution of travel distances and times across the United States.
California had the most practicing neuro-ophthalmologists out of any state (50), whereas 4 states (DE, MT, SD, and WY) had none. Washington, DC and MA had the most neuro-ophthalmologists per capita. The average travel distance and time to the nearest neuro-ophthalmologists were found to be 40.90 miles and 46.50 minutes, respectively, although a large portion of western plains and mountain regions had travel times of over 120 minutes. Patients in rural areas had longer travel times than those in urban areas, and Native American patients had the longest travel times of any racial or ethnic group.
The travel time to see a neuro-ophthalmologist varies widely by state, region, and rurality, with Native American patients and rural patients being disproportionately affected. By identifying the areas with the greatest travel burdens, future policies can work to alleviate these potential barriers to care.
Background:
Postoperative multiple sclerosis (MS) relapses are a concern among patients and providers.
Objective:
To determine whether MS relapse risk is higher postoperatively.
Methods:
Data were ...extracted from medical records of MS patients undergoing surgery at a tertiary center (2000–2016). Conditional logistic regression estimated within-patient unadjusted and age-adjusted odds of postoperative versus preoperative relapse.
Results:
Among 281 patients and 609 surgeries, 12 postoperative relapses were identified. The odds of postoperative versus preoperative relapse in unadjusted (odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.18–1.79; p = 0.33) or age-adjusted models (OR = 0.66, 95% CI = 0.20–2.16; p = 0.49) were not increased.
Conclusions:
Surgery/anesthesia exposure did not increase postoperative relapse risk. These findings require confirmation in larger studies.
Infectious cDNA clones of RNA viruses are important research tools, but flavivirus cDNA clones have proven difficult to assemble and propagate in bacteria. This has been attributed to genetic ...instability and/or host cell toxicity, however the mechanism leading to these difficulties has not been fully elucidated. Here we identify and characterize an efficient cryptic bacterial promoter in the cDNA encoding the dengue virus (DENV) 5' UTR. Following cryptic transcription in E. coli, protein expression initiated at a conserved in-frame AUG that is downstream from the authentic DENV initiation codon, yielding a DENV polyprotein fragment that was truncated at the N-terminus. A more complete understanding of constitutive viral protein expression in E. coli might help explain the cloning and propagation difficulties generally observed with flavivirus cDNA.
Nonarteritic anterior ischemic optic neuropathy (NAION) is a devastating ocular condition causing permanent vision loss. Little is known about risk factors for developing this disease. We assessed ...demographic, systemic, and ocular factors associated with NAION.
Retrospective longitudinal cohort study.
Beneficiaries between 40 and 75 years old without NAION at baseline enrolled in a large U.S. managed care network.
Enrollees were monitored continuously for ≥2 years between 2001 and 2014 to identify those newly diagnosed with NAION (International Classification of Diseases, 9th Revision, Clinical Modification ICD-9-CM code 377.41). All persons were under ophthalmic surveillance and all cases had ≥1 confirmatory ICD-9-CM code for NAION during follow-up.
Multivariable Cox regression modeling was used to generate hazard ratios (HRs) with 95% confidence intervals (CIs) to describe the statistical relationship between selected demographic characteristics, systemic and ocular conditions, and the hazard of developing NAION.
Of 1 381 477 eligible enrollees, 977 (0.1%) developed NAION during a mean ± standard deviation (SD) follow-up of 7.8±3.1 years. The mean ± SD age for NAION cases at the index date was 64.0±9.2 years vs. 58.4±9.4 years for the remainder of the beneficiaries. After adjustment for confounding factors, each additional year older was associated with a 2% increased hazard of NAION (HR = 1.02; 95% CI: 1.01-1.03). Female subjects had a 36% decreased hazard of developing NAION (HR = 0.64; 95% CI: 0.55-0.74) compared with male subjects. Compared with whites, Latinos had a 46% decreased hazard of developing NAION (HR = 0.54; 95% CI: 0.36-0.82), whereas African ancestry was not significantly associated with NAION (HR = 0.91; 95% CI: 0.72-1.15). Systemic diseases associated with NAION included hypertension (HR = 1.62; 95% CI: 1.26-2.07) and hypercoagulable states (HR = 2.46; 95% CI: 1.51-4.00). Although diabetes mellitus (DM) was not significantly associated with NAION compared with those without DM (P = 0.45), patients with end-organ involvement from DM had a 27% increased hazard of NAION relative to those with uncomplicated DM (HR = 1.27; 95% CI: 1.01-1.59). Ocular diseases associated with NAION were age-related macular degeneration (HR = 1.29; 95% CI: 1.08-1.54) and retinal vein occlusion (HR = 3.94; 95% CI: 3.11-4.99).
Our study identified several modifiable risk factors that may be associated with NAION. Should future studies confirm these findings, they may offer opportunities to prevent or treat this debilitating condition.
Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system ...will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs.
Highlights • Pregnant Long–Evans rats showed distinct anxiety-like behavior in the EPM. • High anxiety in dams was correlated with maternal care after maternal deprivation. • Adult males that ...received more licking/grooming showed low anxiety-like behavior. • Amygdala brain-derived neurotrophin factor was associated with offspring anxiety.
In 2012 Markarian 421 underwent the largest flare ever observed in this blazar at radio frequencies. In the present study, we start exploring this unique event and compare it to a less extreme event ...in 2013. We use 15 GHz radio data obtained with the Owens Valley Radio Observatory 40-m telescope, 95 GHz millimetre data from the Combined Array for Research in Millimeter-Wave Astronomy, and GeV γ-ray data from the Fermi Gamma-ray Space Telescope. The radio light curves during the flaring periods in 2012 and 2013 have very different appearances, in both shape and peak flux density. Assuming that the radio and γ-ray flares are physically connected, we attempt to model the most prominent sub-flares of the 2012 and 2013 activity periods by using the simplest possible theoretical framework. We first fit a one-zone synchrotron self-Compton (SSC) model to the less extreme 2013 flare and estimate parameters describing the emission region. We then model the major γ-ray and radio flares of 2012 using the same framework. The 2012 γ-ray flare shows two distinct spikes of similar amplitude, so we examine scenarios associating the radio flare with each spike in turn. In the first scenario, we cannot explain the sharp radio flare with a simple SSC model, but we can accommodate this by adding plausible time variations to the Doppler beaming factor. In the second scenario, a varying Doppler factor is not needed, but the SSC model parameters require fine-tuning. Both alternatives indicate that the sharp radio flare, if physically connected to the preceding γ-ray flares, can be reproduced only for a very specific choice of parameters.
We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many ...cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions < 10 μm diameter; we termed this microscopic donor matrix "cartilage dust (CD)". Using a microwell platform, we show that ~0.83 μg CD can be rapidly and efficiently incorporated into single multicellular aggregates formed from 180 bone marrow mesenchymal stem/stromal cells (MSC) each. The microwell platform enabled the rapid manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage tissues; the incorporation of CD enhanced tissue size and matrix content, but did not enhance chondrogenic gene expression.
Genetically diverse RNA viruses like dengue viruses (DENVs) segregate into multiple, genetically distinct, lineages that temporally arise and disappear on a regular basis. Lineage turnover may occur ...through multiple processes such as, stochastic or due to variations in fitness. To determine the variation of fitness, we measured the distribution of fitness within DENV populations and correlated it with lineage extinction and replacement. The fitness of most members within a population proved lower than the aggregate fitness of populations from which they were drawn, but lineage replacement events were not associated with changes in the distribution of fitness. These data provide insights into variations in fitness of DENV populations, extending our understanding of the complexity between members of individual populations.
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