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1.
Water Res ; 259: 121833, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38865913

ABSTRACT

Antibiotic resistance is a serious global health issue, resulting in at least 1.2 million deaths in 2019. The environment is a potentially important reservoir of antibiotic resistance; however, the fate of Antibiotic Resistance Genes (ARGs) in the environment remains poorly characterized. One important environmental source of ARGs is manure used as a soil amendment. ARGs from manure may then enter nearby flowing waterbodies, where the factors governing their downstream transport remain unknown. To address this, we conducted experiments by spiking cattle manure in an artificial stream to estimate removal rates (k; m-1) for three ARGs (mefA, tetQ, and tetW) and a ruminant fecal marker (bacR). We then used a Stochastic Mobile-Immobile Model (SMIM) to separate the overall removal into two components, rs, and rh, corresponding to immobilizations in the surface (i.e., water column) and subsurface (i.e., streambed), respectively. Finally, we applied the SMIM across four model streams to predict the downstream travel distance of ARGs and bacR. Our results showed measurable removal for all targets in all experimental replicates (n = 3) and no differences were found in the removal rates among replicates for any target (ANCOVA; p > 0.05). We found that the removal of bacR was significantly lower than tetW (p < 0.05) and slightly lower than mefA (p = 0.088), while tetQ removal was slightly different from tetW's (p = 0.072). We also found that rh values were orders of magnitude larger than rs for ARGs and bacR (t-test; p < 0.05). These findings suggest that ARGs and bacR are being removed from the water column through immobilization reactions occurring in the streambed. Additionally, we predicted that the 90 % removal (or D90) of targets occurs within the first 500 m in all model streams except in a slow-flow pastoral stream, which required 1400 m of downstream transport for 90 % removal. Our findings and model stand out as promising tools to predict the fate of ARGs in streams and will contribute to improving and managing agricultural practices that employ animal manure.

2.
Sci Total Environ ; 905: 167132, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37730047

ABSTRACT

Lead (Pb) exposures from soil and dust ingestion contribute to children's blood lead levels (BLLs) in the United States. The U.S. Environmental Protection Agency (EPA)'s Strategy to Reduce Lead Exposures and Disparities in U.S. Communities and the Federal Action Plan to Reduce Childhood Lead Exposure describe multi-pronged collaborative approaches. These include reducing multi-media lead exposures nationally using analytical tools such as EPA's Stochastic Human Exposure and Dose Simulation model for lead [SHEDS-Pb; formerly known as SHEDS-IEUBK (Integrated Exposure Uptake Biokinetic model)], which was initially developed and applied with a focus on children's drinking water exposures. In this study we applied SHEDS-Pb to determine what residential soil Pb and dust Pb concentrations (individually and their sum) can keep BLLs of potentially exposed young children in the general U.S. population below specified values, considering aggregate exposures from water, soil, dust, food, and air. We considered two age groups (1 to <2 years and 2 to <6 years), two BLL values (5 µg/dL and 3.5 µg/dL), and two population percentiles (95th and 97.5th). Sensitivity analyses were conducted using several alternative model inputs and data sets, yielding 15 scenarios summarized in the paper. Of those scenarios, we focused on ones with the most recent science and available data. Modeled soil Pb concentrations by age group, population percentile and reference BLL scenarios for the focus scenarios ranged from 70 ppm to 220 ppm; and modeled dust Pb concentrations ranged from 110 ppm to 240 ppm. These results are consistent with current soil and dust Pb concentrations in the U.S. general population and are lower than most of the current U.S. Federal standards. Estimated BLLs compared well with measured BLLs from CDC's NHANES 2009-2016 (0-27 % relative error for focus scenarios). This analysis can be used to inform EPA and other federal Pb efforts.


Subject(s)
Drinking Water , Lead , Child , Humans , United States , Child, Preschool , Lead/analysis , Environmental Exposure/analysis , Dust/analysis , Soil , Nutrition Surveys , Drinking Water/analysis
3.
Osteoarthritis Cartilage ; 28(4): 446-452, 2020 04.
Article in English | MEDLINE | ID: mdl-32084589

ABSTRACT

OBJECTIVE: To describe the incidence and progression of radiographic and symptomatic hand osteoarthritis (rHOA and sxHOA) in a large community-based cohort. DESIGN: Data were from the Johnston County OA Project (1999-2015, 12 ± 1.2 years follow-up, age 45+). Participants had bilateral hand radiographs each visit, read for Kellgren-Lawrence grade (KLG) at 30 joints. We defined rHOA as KLG ≥2 in ≥1 joint. SxHOA was defined in a hand/joint with rHOA and self-reported symptoms or tenderness on exam. Incidence was assessed in those without, while progression was assessed in those with, baseline rHOA. Proportions or medians are reported; differences by sex and race were assessed using models appropriate for dichotomous or continuous definitions, additionally adjusted for age, education, body mass index (BMI), and weight change. RESULTS: Of 800 participants (68% women, 32% African American, mean age 60 years), 327 had baseline rHOA and were older, more often white and female, than those without rHOA (n = 473). The incidence of HOA was high, for rHOA (60%) and for sxHOA (13%). Women were more likely than men to have incident HOA, particularly for distal interphalangeal joint radiographic osteoarthritis (DIP rOA) (adjusted odds ratios (aOR) 1.60 95% confidence intervals (95% CI) [1.03, 2.49]) and sxHOA (aOR 2.98 [1.50, 5.91]). Progressive HOA was more similar by sex, although thumb base rOA progressed more frequently in women than in men (aOR 2.56 [1.44, 4.55]). Particularly HOA incidence, but also progression, was more frequent among whites compared with African Americans. CONCLUSION: This study provides much needed information about the natural history of HOA, a common and frequently debilitating condition, in the general population.


Subject(s)
Hand Joints/diagnostic imaging , Osteoarthritis/epidemiology , Black or African American , Aged , Carpometacarpal Joints/diagnostic imaging , Carpometacarpal Joints/physiopathology , Cohort Studies , Disease Progression , Female , Finger Joint/diagnostic imaging , Finger Joint/physiopathology , Hand Joints/physiopathology , Humans , Incidence , Male , Metacarpophalangeal Joint/diagnostic imaging , Metacarpophalangeal Joint/physiopathology , Middle Aged , North Carolina/epidemiology , Osteoarthritis/diagnostic imaging , Osteoarthritis/ethnology , Osteoarthritis/physiopathology , Radiography , White People
4.
J Anim Sci ; 95(3): 1124-1131, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28380515

ABSTRACT

Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in North American beef cattle. () is the bacterial pathogen most frequently isolated from cattle with BRD and the prevalence of antimicrobial resistance in this pathogen has been increasing. Administration of antimicrobials to prevent BRD is commonplace in stocker cattle, but the impact of this practice on emergence of resistance in is unknown. High risk, sale barn origin bull and steer calves ( = 169) were transported to a stocker facility in central Georgia and sampled via deep nasopharyngeal swab (NPS) at arrival processing. All calves received the macrolide antimicrobial tulathromycin (2.5 mg/kg subcutaneously) at arrival processing. A second NPS was collected from each calf 10 to 14 d after arrival. The occasional calves diagnosed and treated for BRD prior to 10 to 14 d were swabbed and cultured prior to treatment. Swabs were submitted for culture and antimicrobial susceptibility testing using the Kirby-Bauer disk diffusion method. Of the 169 cattle enrolled, 27 (16.0%) were culture positive for at arrival processing and of these, a multi-drug resistant (MDR) strain of was detected in 1 (3.7%). In contrast, 123 (72.8%) cattle were culture positive for at second sampling and of these, a MDR strain of was detected in 122 (99.2%). The proportions of cattle culture positive for and positive for MDR at arrival processing and at second sampling were significantly different ( < 0.001). At the level of the individual bacterial isolate, 366 individual isolates were collected from the calves at the time of the second sampling. Of these isolates, 361 (98.6%) were intermediate or resistant to all macrolides tested (tilmicosin, gamithromycin, tulathromycin) and the fluoroquinolone enrofloxacin. In addition, 254 isolates (69.4%) were intermediate or resistant to florfenicol and 4 (1.1%) were intermediate or resistant to ceftiofur. There was a significant difference in the proportion of isolates resistant to all of the drug classes except cephalosporins at arrival processing versus second sampling ( < 0.001). Our results show that there was an increase in the proportion of calves positive for from arrival processing to second sampling, and that there was an increase in the proportion of calves that had MDR strains of detected from arrival processing to second sampling. More research is needed to understand the role of metaphylaxis on MDR in and the impact of MDR on morbidity and mortality in stocker cattle.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cattle Diseases/microbiology , Drug Resistance, Multiple, Bacterial , Mannheimia haemolytica/drug effects , Pasteurellaceae Infections/veterinary , Animals , Cattle , Male , Pasteurellaceae Infections/microbiology
5.
J Synchrotron Radiat ; 21(Pt 1): 66-75, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24365918

ABSTRACT

Hard X-ray fluorescence microscopy is one of the most sensitive techniques for performing trace elemental analysis of biological samples such as whole cells and tissues. Conventional sample preparation methods usually involve dehydration, which removes cellular water and may consequently cause structural collapse, or invasive processes such as embedding. Radiation-induced artifacts may also become an issue, particularly as the spatial resolution increases beyond the sub-micrometer scale. To allow imaging under hydrated conditions, close to the `natural state', as well as to reduce structural radiation damage, the Bionanoprobe (BNP) has been developed, a hard X-ray fluorescence nanoprobe with cryogenic sample environment and cryo transfer capabilities, dedicated to studying trace elements in frozen-hydrated biological systems. The BNP is installed at an undulator beamline at sector 21 of the Advanced Photon Source. It provides a spatial resolution of 30 nm for two-dimensional fluorescence imaging. In this first demonstration the instrument design and motion control principles are described, the instrument performance is quantified, and the first results obtained with the BNP on frozen-hydrated whole cells are reported.


Subject(s)
Biosensing Techniques , Cold Temperature , Fluorescent Dyes , Freezing , Microscopy, Fluorescence
6.
J Am Med Dir Assoc ; 14(2): 114-8, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23273855

ABSTRACT

OBJECTIVES: In advanced dementia, feeding problems are nearly universal, and families face difficult decisions about feeding options. Initial interviews for a randomized trial were used to describe surrogates' perceptions of feeding options, and to determine whether a decision aid on feeding options in advanced dementia would improve knowledge, reduce expectation of benefit from tube feeding, and reduce conflict over treatment choices for persons with advanced dementia. DESIGN: Semistructured interview with prestudy and poststudy design for surrogates in the intervention group. SETTING: Twenty-four skilled nursing facilities across North Carolina participating in a cluster randomized trial. PARTICIPANTS: Two hundred and fifty-five surrogate decision makers for nursing home residents with advanced dementia and feeding problems, in control (n = 129) and intervention (n = 126) groups. INTERVENTION: For intervention surrogates only, an audiovisual-print decision aid provided information on dementia, feeding problems in dementia, advantages and disadvantages of feeding tubes or assisted oral feeding options, and the role of surrogates in making these decisions. MEASUREMENTS: The interview included open-ended items asking surrogates to report advantages and disadvantages of tube feeding and assisted oral feeding. Knowledge of feeding options was measured with 19 true/false items and items measuring expectation of benefit from tube feeding. Surrogates reported which of these two feeding options they preferred for the person with dementia, and how confident they were in this choice; their level of conflict about the choice was measured using the decisional conflict scale. RESULTS: Before the decision aid, surrogates described advantages and disadvantages of assisted oral feeding and tube feeding in practical, ethical, and medical terms. After review of the decision aid, intervention surrogates had improved knowledge scores (15.5 vs 16.8; P < .001), decreased expectation of benefits from tube feeding (2.73 vs 2.32; P = .001), and reduced decisional conflict (2.24 vs 1.91; P < .001). Surrogates preferred assisted oral feeding initially and reported more certainty about this choice after the decision aid. CONCLUSIONS: A structured decision aid can be used to improve decision making about feeding options in dementia care.


Subject(s)
Decision Support Techniques , Dementia/physiopathology , Feeding and Eating Disorders/prevention & control , Feeding and Eating Disorders/physiopathology , Third-Party Consent , Decision Making , Female , Humans , Interviews as Topic , Male , Middle Aged , North Carolina
8.
Neurochem Res ; 37(6): 1335-43, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22367451

ABSTRACT

Sandhoff Disease (SD) involves the CNS accumulation of ganglioside GM2 and asialo-GM2 (GA2) due to inherited defects in the ß-subunit gene of ß-hexosaminidase A and B (Hexb gene). Substrate reduction therapy, utilizing imino sugar N-butyldeoxygalactonojirimycin (NB-DGJ), reduces ganglioside biosynthesis and levels of stored GM2 in SD mice. Intracranial transplantation of Neural Stem Cells (NSCs) can provide enzymatic cross correction, to help reduce ganglioside storage and extend life. Here we tested the effect of NSCs and NB-DGJ, alone and together, on brain ß-hexosaminidase activity, GM2, and GA2 content in juvenile SD mice. The SD mice received either cerebral NSC transplantation at post-natal day 0 (p-0), intraperitoneal injection of NB-DGJ (500 mg/kg/day) from p-9 to p-15, or received dual treatments. The brains were analyzed at p-15. ß-galactosidase staining confirmed engraftment of lacZ-expressing NSCs in the cerebral cortex. Compared to untreated and sham-treated SD controls, NSC treatment alone provided a slight increase in Hex activity and significantly decreased GA2 content. However, NSCs had no effect on GM2 content when analyzed at p-15. NB-DGJ alone had no effect on Hex activity, but significantly reduced GM2 and GA2 content. Hex activity was slightly elevated in the NSC + drug-treated mice. GM2 and GA2 content in the dual treated mice were similar to that of the NB-DGJ treated mice. These data indicate that NB-DGJ alone was more effective in targeting storage in juvenile SD mice than were NSCs alone. No additive or synergistic effect between NSC and drug was found in these juvenile SD mice.


Subject(s)
1-Deoxynojirimycin/analogs & derivatives , Neural Stem Cells/transplantation , Sandhoff Disease/therapy , 1-Deoxynojirimycin/therapeutic use , Animals , G(M2) Ganglioside , Hexosaminidase B/metabolism , Mice , Sandhoff Disease/drug therapy , beta-N-Acetylhexosaminidases/genetics
9.
Regen Med ; 5(3): 345-63, 2010 May.
Article in English | MEDLINE | ID: mdl-20230312

ABSTRACT

AIM: To determine whether transcriptional reprogramming is capable of reversing the developmental aging of normal human somatic cells to an embryonic state. MATERIALS & METHODS: An isogenic system was utilized to facilitate an accurate assessment of the reprogramming of telomere restriction fragment (TRF) length of aged differentiated cells to that of the human embryonic stem (hES) cell line from which they were originally derived. An hES-derived mortal clonal cell strain EN13 was reprogrammed by SOX2, OCT4 and KLF4. The six resulting induced pluripotent stem (iPS) cell lines were surveyed for telomere length, telomerase activity and telomere-related gene expression. In addition, we measured all these parameters in widely-used hES and iPS cell lines and compared the results to those obtained in the six new isogenic iPS cell lines. RESULTS: We observed variable but relatively long TRF lengths in three widely studied hES cell lines (16.09-21.1 kb) but markedly shorter TRF lengths (6.4-12.6 kb) in five similarly widely studied iPS cell lines. Transcriptome analysis comparing these hES and iPS cell lines showed modest variation in a small subset of genes implicated in telomere length regulation. However, iPS cell lines consistently showed reduced levels of telomerase activity compared with hES cell lines. In order to verify these results in an isogenic background, we generated six iPS cell clones from the hES-derived cell line EN13. These iPS cell clones showed initial telomere lengths comparable to the parental EN13 cells, had telomerase activity, expressed embryonic stem cell markers and had a telomere-related transcriptome similar to hES cells. Subsequent culture of five out of six lines generally showed telomere shortening to lengths similar to that observed in the widely distributed iPS lines. However, the clone EH3, with relatively high levels of telomerase activity, progressively increased TRF length over 60 days of serial culture back to that of the parental hES cell line. CONCLUSION: Prematurely aged (shortened) telomeres appears to be a common feature of iPS cells created by current pluripotency protocols. However, the spontaneous appearance of lines that express sufficient telomerase activity to extend telomere length may allow the reversal of developmental aging in human cells for use in regenerative medicine.


Subject(s)
Aging , Pluripotent Stem Cells/transplantation , Regenerative Medicine/methods , Regenerative Medicine/trends , Cell Differentiation , Cellular Senescence , Embryonic Stem Cells/cytology , Gene Expression Profiling , HeLa Cells , Humans , Karyotyping , Kruppel-Like Factor 4 , Microscopy, Phase-Contrast/methods , Pluripotent Stem Cells/cytology , Polymorphism, Single Nucleotide , Telomere/ultrastructure , Time Factors , Transcription, Genetic
11.
Nucleic Acids Res ; 35(12): 3953-62, 2007.
Article in English | MEDLINE | ID: mdl-17553834

ABSTRACT

We present a bacterial genome computational analysis pipeline, called GenVar. The pipeline, based on the program GeneWise, is designed to analyze an annotated genome and automatically identify missed gene calls and sequence variants such as genes with disrupted reading frames (split genes) and those with insertions and deletions (indels). For a given genome to be analyzed, GenVar relies on a database containing closely related genomes (such as other species or strains) as well as a few additional reference genomes. GenVar also helps identify gene disruptions probably caused by sequencing errors. We exemplify GenVar's capabilities by presenting results from the analysis of four Brucella genomes. Brucella is an important human pathogen and zoonotic agent. The analysis revealed hundreds of missed gene calls, new split genes and indels, several of which are species specific and hence provide valuable clues to the understanding of the genome basis of Brucella pathogenicity and host specificity.


Subject(s)
Brucella/genetics , Computational Biology/methods , Genetic Variation , Genome, Bacterial , Genomics/methods , Amino Acid Sequence , Bacterial Proteins/genetics , Base Sequence , Brucella/pathogenicity , DNA, Intergenic/chemistry , Genes, Bacterial , Molecular Sequence Data , Polymorphism, Genetic , Software , Virulence Factors/genetics
12.
Nucleic Acids Res ; 35(Database issue): D401-6, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17142235

ABSTRACT

The PathoSystems Resource Integration Center (PATRIC) is one of eight Bioinformatics Resource Centers (BRCs) funded by the National Institute of Allergy and Infection Diseases (NIAID) to create a data and analysis resource for selected NIAID priority pathogens, specifically proteobacteria of the genera Brucella, Rickettsia and Coxiella, and corona-, calici- and lyssaviruses and viruses associated with hepatitis A and E. The goal of the project is to provide a comprehensive bioinformatics resource for these pathogens, including consistently annotated genome, proteome and metabolic pathway data to facilitate research into counter-measures, including drugs, vaccines and diagnostics. The project's curation strategy has three prongs: 'breadth first' beginning with whole-genome and proteome curation using standardized protocols, a 'targeted' approach addressing the specific needs of researchers and an integrative strategy to leverage high-throughput experimental data (e.g. microarrays, proteomics) and literature. The PATRIC infrastructure consists of a relational database, analytical pipelines and a website which supports browsing, querying, data visualization and the ability to download raw and curated data in standard formats. At present, the site warehouses complete sequences for 17 bacterial and 332 viral genomes. The PATRIC website (https://patric.vbi.vt.edu) will continually grow with the addition of data, analysis and functionality over the course of the project.


Subject(s)
Bioterrorism , Databases, Genetic , Proteobacteria/genetics , RNA Viruses/genetics , Genomics , Internet , Proteobacteria/metabolism , Proteobacteria/pathogenicity , Proteomics , RNA Viruses/metabolism , RNA Viruses/pathogenicity , Systems Integration , User-Computer Interface
13.
J Mater Sci Mater Med ; 17(12): 1227-36, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17143753

ABSTRACT

The use of polymer based drug delivery systems in dentistry is a relatively new area of research with the exception of the inhibition of secondary caries by the release of fluoride ions from polyalkenoate cements and their predecessors silicate cements. The present study was to test on orally biocompatible material, ethylene vinyl acetate copolymer (EVA), for release of antiviral drugs at oral therapeutic levels over extended periods of time. We also determined their stability during film casting and release. Materials studied include gancyclovir (GCY), acyclovir (ACY), dichloromethane (DCM), and ethylene vinyl acetate (EVA). The square films (3 x 3 x 0.1 cm) were prepared from the dry sheet obtained by solvent evaporation of polymer casting solutions. These solutions were made of EVA and the drug (40:1) in 70 ml of dichloromethane at 38 degrees C. Then drug release characteristics from the drug loaded films were examined at 37 degrees C for a minimum of 14 days in 10 ml medium (ddwater) replaced daily. Kinetics of drug release were followed by spectral measurements using previously determined lambda(max) values (GCY = 250 nm; ACY = 253 nm). A minimum of three samples was tested and reproducible results were obtained. Drug stability (ACY) during film casting and its release was determined using 1H NMR spectrometer (Bruker DRX-500 and 400). Rate of drug release was determined from the part of the curve (rate vs. time) after the onset of the "burst." Although GCY has a larger molecular weight (255) than ACY (225), GCY exhibited about three times higher rate of release than ACY. This difference in rate values may be explained due to its relatively greater solubility in EVA, facilitating faster diffusion of the molecules through the channels present in EVA. This is consistent with the observation that the rate at which drug molecules diffuse through the channels of the polymer, can be increased by decreasing the molecular weight. In the case of ACY, the molecules may be undergoing molecular associations, perhaps dimerization or trimerization in addition to its lower solubility in EVA. The diffusion of ACY tends to be slower under these circumstances compared to GCY resulting in lower rate value than in the case of GCY. Biological studies revealed that ACY exhibited a remarkable decrease in a number of viral organisms present in virus infected cell culture system using real-time polymerase chain reaction (RT-PCR). NMR analysis indicates that the chemical structure of the drug remains stable during film casting process and release.


Subject(s)
Acyclovir/pharmacokinetics , Antiviral Agents/pharmacokinetics , Drug Delivery Systems , Polyethylene/pharmacokinetics , Polyvinyls/pharmacokinetics , Vinyl Compounds/pharmacokinetics , Biocompatible Materials/pharmacokinetics , Cell Line, Transformed , Drug Stability , Humans , Methylene Chloride/pharmacokinetics , Nuclear Magnetic Resonance, Biomolecular
14.
Best Pract Res Clin Haematol ; 19(1): 205-42, 2006.
Article in English | MEDLINE | ID: mdl-16377551

ABSTRACT

The desire to rid the blood supply of pathogens of all types has led to the development of many technologies aimed at the same goal--eradication of the pathogen(s) without harming the blood cells or generating toxic chemical agents. This is a very ambitious goal, and one that has yet to be achieved. One approach is to shun the 'one size fits all' concept and to target pathogen-reduction agents at the Individual component types. This permits the development of technologies that might be compatible with, for example, plasma products but that would be cytocidal and thus incompatible with platelet concentrates or red blood cell units. The technologies to be discussed include solvent detergent and methylene blue treatments--designed to inactivate plasma components and derivatives; psoralens (S-59--amotosalen) designed to pathogen-reduce units of platelets; and two products aimed at red blood cells, S-303 (a Frale--frangible anchor-linker effector compound) and Inactine (a binary ethyleneimine). A final pathogen-reduction material that might actually allow one material to inactivate all three blood components--riboflavin (vitamin B2)--is also under development. The sites of action of the amotosalen (S-59), the S-303 Frale, Inactine, and riboflavin are all localized in the nucleic acid part of the pathogen. Solvent detergent materials act by dissolving the plasma envelope, thus compromising the integrity of the pathogen membrane and rendering it non-infectious. By disrupting the pathogen's ability to replicate or survive, its infectivity is removed. The degree to which bacteria and viruses are affected by a particular pathogen-reducing technology relates to its Gram-positive or Gram-negative status, to the sporulation characteristics for bacteria, and the presence of lipid or protein envelopes for viruses. Concerns related to photoproducts and other breakdown products of these technologies remain, and the toxicology of pathogen-reduction treatments is a major ongoing area of investigation. Clearly, regulatory agencies have a major role to play in the evaluation of these new technologies. This chapter will cover the several types of pathogen-reduction systems, mechanisms of action, the inactivation efficacy for specific types of pathogens, toxicology of the various systems and the published research and clinical trial data supporting their potential usefulness. Due to the nature of the field, pathogen reduction is a work in progress and this review should be considered as a snapshot in time rather than a clear picture of what the future will bring.


Subject(s)
Anti-Infective Agents/therapeutic use , Blood-Borne Pathogens , Blood/drug effects , Blood/microbiology , Anti-Infective Agents/pharmacology , Blood-Borne Pathogens/radiation effects , Detergents/pharmacology , Detergents/therapeutic use , Graft vs Host Disease/drug therapy , Graft vs Host Disease/microbiology , Graft vs Host Disease/prevention & control , Humans , Methylene Blue/pharmacology , Methylene Blue/therapeutic use , Riboflavin/pharmacology , Riboflavin/therapeutic use , Transfusion Reaction
15.
Article in English | MEDLINE | ID: mdl-16315610

ABSTRACT

Neural stem and progenitor cells express a variety of receptors that enable them to sense and react to signals emanating from physiological and pathophysiological conditions in the brain as well as elsewhere in the body. Many of these receptors and were first described in investigations of the immune system, particularly with respect to hematopoietic stem cells. This emerging view of neurobiology has two major implications. First, many phenomena known from the hematopoietic system may actually be generalizable to stem cells from many organ systems, reflecting the cells' progenitor-mediated regenerative potential. Second, regenerative interfaces may exist between diverse organ systems; populations of cells of neuroectodermal and hematopoietic origin may interact to play a crucial role in normal brain physiology, pathology, and repair. An understanding of the origins of signals and the neural progenitors' responses might lead to the development of effective therapeutic strategies to counterbalance acute and chronic neurodegenerative processes. Such strategies may include modifying and modulating cells with regenerative potential in subtle ways. For example, stem cells might be able to detect pathology-associated signals and be used as "interpreters" to mediate drug and other therapeutic interventions. This review has focused on the role of inflammation in brain repair. We propose that resident astroglia and blood-born cells both contribute to an inflammatory signature that is unique to each kind of neuronal degeneration or injury. These cells play a key role in coordinating the neural progenitor cell response to brain injury by exerting direct and indirect environmentally mediated influence on neural progenitor cells. We suggest that investigations of the neural progenitor-immunologic interface will provide valuable data related to the mechanisms by which endogenous and exogenous neural progenitor cells react to brain pathology, ultimately aiding in the design of more effective therapeutic applications of stem cell biology. Such improvements will include: (1) ascertaining the proper timing for implanting exogenous neural progenitor cells in relation to the administration of anti-inflammatory agents; (2) identifying what types of molecules might be administered during injury to enhance the mobilization and differentiation of endogenous and exogenous neural progenitor cells while also inhibiting the detrimental aspects of the inflammatory reaction; (3) divining clues as to which molecules may be required to change the lesioned environment in order to invite the homing of reparative neural progenitor cells.


Subject(s)
Immune System , Nervous System/pathology , Animals , Brain/pathology , Cell Differentiation , Cell Lineage , Humans , Inflammation , Models, Biological , Neuroglia/pathology , Neurons/metabolism , Neurons/pathology , Stem Cells/cytology
16.
Dev Biol (Basel) ; 120: 39-44, 2005.
Article in English | MEDLINE | ID: mdl-16050154

ABSTRACT

In conclusion, as of 2004, it appears that in the United States in some hospitals, the use of LR blood products will probably remain as SLR rather than PSULR, due primarily to economic pressures. While some blood centres are slowly converting to ULR, there remains a mix of negative and positive feelings among physicians that make adoption of a national PSULR Standard of Care difficult. What is clear is that leukoreduction filters will cost more than the 170 um screen ("clot") filter. The use of PSULR to decrease the incidence of FNHTR, to decrease the incidence of HLA alloimmunization, and its use in lieu of CMV-seronegative blood products is well supported in the medical literature. However, this issue will probably continue to be revisited and debated for some time before a national standard policy for PSULR is adopted. Finally, we believe that despite increasing economic pressures and worsening budgetary constraints, the decision to adopt PSULR should rest primarily on medical reasons: as a means of improving patient care. In the view of the authors, pre-storage universal leukoreduction qualifies as a significant and medically justifiable improvement in the care of all hospital patients.


Subject(s)
Hospitals, University/organization & administration , Leukocytes/cytology , Budgets , Cell Separation , Connecticut , Cytomegalovirus Infections/transmission , HLA Antigens/immunology , Humans , Transfusion Reaction
17.
Cell Transplant ; 14(4): 193-202, 2005.
Article in English | MEDLINE | ID: mdl-15929554

ABSTRACT

Neural stem cells (NSCs) of the central nervous system (CNS) recently have attracted a great deal of interest not only because of their importance in basic research on neural development, but also in terms of their therapeutic potential in neurological diseases, such as Parkinson's disease (PD). To examine if genetically modified NSCs are a suitable source for the cell and gene therapy of PD, an immortalized mouse NSC line, C17.2, was transduced with tyrosine hydroxylase (TH) gene and with GTP cyclohydrolase 1 (GTPCH1) gene, which are important enzymes in dopamine biosynthesis. The expression of TH in transduced C17.2-THGC cells was confirmed by RT-PCR, Western blot analysis, and immunocytochemistry, and expression of GTPCH1 by RT-PCR. The level of L-DOPA released by C17.2-THGC cells, as determined by HPLC assay, was 3793 pmol/10(6) cells, which is 760-fold higher than that produced by C17.2-TH cells, indicating that GTPCH1 expression is important for L-DOPA production by transduced C17.2 cells. Following the implantation of C17.2-THGcC NSCs into the striata of parkinsonian rats, a marked improvement in amphetamine-induced turning behavior was observed in parkinsonian rats grafted with C17.2-THGC cells but not in the control rats grafted with C17.2 cells. These results indicate that genetically modified NSCs grafted into the brain of the parkinsonian rats are capable of survival, migration, and neuronal differentiation. Collectively, these results suggest that NSCs have great potential as a source of cells for cell therapy and an effective vehicle for therapeutic gene transfer in Parkinson's disease.


Subject(s)
GTP Cyclohydrolase/genetics , Genetic Therapy/methods , Neurons/physiology , Parkinson Disease/therapy , Stem Cell Transplantation , Tyrosine 3-Monooxygenase/genetics , Animals , Behavior, Animal , Cell Differentiation , Female , GTP Cyclohydrolase/metabolism , Graft Survival , Humans , Levodopa/metabolism , Neurons/cytology , Rats , Rats, Sprague-Dawley , Stem Cells/physiology , Transduction, Genetic , Tyrosine 3-Monooxygenase/metabolism
18.
Vox Sang ; 89(1): 44-8, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15938739

ABSTRACT

BACKGROUND AND OBJECTIVES: Red blood cell (RBC) storage systems are licensed based on their ability to prevent haemolysis and maintain RBC 24-h in vivo recovery. Preclinical testing includes measurement of RBC ATP as a surrogate for recovery, 2,3-diphosphoglycerate (DPG) as a surrogate for oxygen affinity, and free haemoglobin, which is indicative of red cell lysis. The reproducibility of RBC ATP, DPG and haemolysis measurements between centres was investigated. MATERIALS AND METHODS: Five, 4-day-old leucoreduced AS-1 RBC units were pooled, aliquotted and shipped on ice to 14 laboratories in the USA and European Union (EU). Each laboratory was to sample the bag twice on day 7 and measure RBC ATP, DPG, haemoglobin and haemolysis levels in triplicate on each sample. The variability of results was assessed by using coefficients of variation (CV) and analysis of variance. RESULTS: Measurements were highly reproducible at the individual sites. Between sites, the CV was 16% for ATP, 35% for DPG, 2% for total haemoglobin and 54% for haemolysis. For ATP and total haemoglobin, 94 and 80% of the variance in measurements was contributed by differences between sites, and more than 80% of the variance for DPG and haemolysis measurements came from markedly discordant results from three sites and one site, respectively. In descending order, mathematical errors, unvalidated analytical methods, a lack of shared standards and fluid handling errors contributed to the variability in measurements from different sites. CONCLUSIONS: While the methods used by laboratories engaged in RBC storage system clinical trials demonstrated good precision, differences in results between laboratories may hinder comparative analysis. Efforts to improve performance should focus on developing robust methods, especially for measuring RBC ATP.


Subject(s)
2,3-Diphosphoglycerate/analysis , Adenosine Triphosphate/analysis , Blood Preservation/standards , Erythrocytes/chemistry , Hemolysis , Biomarkers/analysis , Erythrocyte Aging , Humans , Observer Variation , Plateletpheresis
19.
Nucleic Acids Res ; 33(3): e26, 2005 Feb 16.
Article in English | MEDLINE | ID: mdl-15716308

ABSTRACT

The serial analysis of gene expression (SAGE) method is used to study global gene expression in cells or tissues in various experimental conditions. However, its reproducibility has not yet been definitively assessed. In this study, we have evaluated the reproducibility of the SAGE method and identified the factors that affect it. The determination coefficient (R2 ) for the reproducibility of SAGE is 0.96. However, there are some factors that can affect the reproducibility of SAGE, such as the replication of concatemers and ditags, the number of sequenced tags and double PCR amplification of ditags. Thus, corrections for these factors must be made to ensure the reproducibility and accuracy of SAGE results. A bioinformatic analysis of SAGE data is also presented in order to eliminate these artifacts. Finally, the current study shows that increasing the number of sequenced tags improves the power of the method to detect transcripts and their regulation by experimental conditions.


Subject(s)
Computational Biology/methods , Gene Expression Profiling/methods , Animals , Artifacts , Genomics/methods , Male , Mice , Mice, Inbred C57BL , Polymerase Chain Reaction , Reproducibility of Results , Sequence Tagged Sites , Transcription, Genetic
20.
Bone Marrow Transplant ; 32(12): 1113-7, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14647264

ABSTRACT

High-dose chemotherapy and autologous stem cell rescue is considered a standard part of initial therapy for patients with multiple myeloma. Therefore, potential transplant candidates are generally treated with dexamethasone-based programs rather than alkylating agents to avoid stem cell toxicity. The optimal mobilizing regimen for patients with multiple myeloma has not been defined. However, aggressive chemotherapy may result in excessive morbidity and cost in this older, immunocompromised population. We retrospectively examined our experience with a well-tolerated regimen of 1.5 g/m(2) cyclophosphamide on day -10 followed by 10 microg/kg G-CSF beginning on day -7 in 50 consecutive patients with multiple myeloma and no prior alkylating agent therapy. Median stem cell collection was 4.88 x 10(6) CD34+ cells/kg per apheresis and 44 patients collected >5 x 10(6) CD34+ cells/kg within 2 days. In 36 patients, more than 10 x 10(6) CD34+ cells/kg were collected including 33 patients who required 1-2 days of collection. One patient required hospitalization for fever/neutropenia and two required weekend apheresis. We conclude that 1.5 g/m(2) cyclophosphamide plus 10 microg/kg G-CSF is a safe, effective, highly predictable mobilizing program that uniformly provided enough stem cells for one transplant and enough stem cells for two transplants.


Subject(s)
Cyclophosphamide/pharmacology , Granulocyte Colony-Stimulating Factor/pharmacology , Hematopoietic Stem Cell Mobilization/methods , Multiple Myeloma/blood , Adult , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Blood Cell Count , Combined Modality Therapy , Cyclophosphamide/adverse effects , Databases, Factual , Dexamethasone/administration & dosage , Doxorubicin/administration & dosage , Female , Fever/etiology , Granulocyte Colony-Stimulating Factor/adverse effects , Humans , Leukapheresis , Male , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/therapy , Neutropenia/etiology , Peripheral Blood Stem Cell Transplantation , Retrospective Studies , Transplantation, Autologous , Vincristine/administration & dosage
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