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2.
Sci Rep ; 11(1): 3202, 2021 02 05.
Article in English | MEDLINE | ID: mdl-33547371

ABSTRACT

Pollinator refuges such as wildflower strips are planted on farms with the goals of mitigating wild pollinator declines and promoting crop pollination services. It is unclear, however, whether or how these goals are impacted by managed honey bee (Apis mellifera L.) hives on farms. We examined how wildflower strips and honey bee hives and/or their interaction influence wild bee communities and the fruit count of two pollinator-dependent crops across 21 farms in the Mid-Atlantic U.S. Although wild bee species richness increased with bloom density within wildflower strips, populations did not differ significantly between farms with and without them whereas fruit counts in both crops increased on farms with wildflower strips during one of 2 years. By contrast, wild bee abundance decreased by 48%, species richness by 20%, and strawberry fruit count by 18% across all farm with honey bee hives regardless of wildflower strip presence, and winter squash fruit count was consistently lower on farms with wildflower strips with hives as well. This work demonstrates that honey bee hives could detrimentally affect fruit count and wild bee populations on farms, and that benefits conferred by wildflower strips might not offset these negative impacts. Keeping honey bee hives on farms with wildflower strips could reduce conservation and pollination services.


Subject(s)
Bees/physiology , Agriculture , Animals , Biodiversity , Crops, Agricultural/physiology , Flowers/physiology , Fruit/physiology , Pollination
3.
J Geophys Res Solid Earth ; 126(12): e2021JB022392, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35865454

ABSTRACT

The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO), launched May 22, 2018 and collecting science data since June 2018, is extending the 15-year data record of Earth mass change established by its predecessor GRACE mission (2002-2017). The GRACE-FO satellites carry onboard a novel technology demonstration instrument for intersatellite ranging, the Laser Ranging Interferometer (LRI), in addition to the microwave interferometer (MWI) carried on GRACE. The LRI has out-performed its in-orbit performance requirements both in terms of accuracy as well as the duration of tracking. Here, we compare and validate LRI-based gravity solutions for January 2019 to September 2020 against the MWI solutions. The comparison between the two sets of gravity solutions shows great similarities in general and nearly perfect consistency at a large hydrologic basin spatial scale (100,000 km2 and above), commonly viewed as the spatial resolution established by GRACE. The comparison in the spectral domain shows differences at the higher degrees of the spectrum, with lower error in the zonal and near zonal terms for the LRI solutions. We conclude that the LRI observations can be used to recover time-varying gravity signals to at least the level of accuracy established by the MWI-based solutions. This is a promising finding, especially when considering the benefits of using the LRI over the MWI, such as the great stability of the instrument and the low occurrence of instrument reboot events.

4.
J Hosp Infect ; 106(1): 20-24, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32569673

ABSTRACT

Respiratory point-of-care testing (POCT) for the detection of influenza A, influenza B and respiratory syncytial virus (RSV) was implemented in response to recent RSV outbreaks at a regional haemato-oncology unit in Glasgow. This descriptive study, undertaken pre- and post-POCT implementation, suggests that POCT reduces the time taken to receive results and increases diagnostic rates in outpatients. It is likely that the reduction in turnaround time afforded by POCT also leads to a faster time to antiviral treatment, prompt isolation and a reduction in the number of hospital-acquired infections.


Subject(s)
Health Plan Implementation , Influenza, Human/diagnosis , Point-of-Care Testing , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Tract Infections/diagnosis , Cohort Studies , Hematology , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Molecular Diagnostic Techniques/instrumentation , Oncology Service, Hospital/statistics & numerical data , Outpatients , Qualitative Research , Respiratory Syncytial Virus, Human/genetics , Respiratory Tract Infections/virology
5.
Methods Enzymol ; 573: 139-60, 2016.
Article in English | MEDLINE | ID: mdl-27372752

ABSTRACT

Lysine acetylation is a posttranslational modification that is carried out by acetyltransferases. The MYST proteins form the largest and most diverse family of acetyltransferases, which regulate gene expression, DNA repair, and cell cycle homeostasis, among other activities, by acetylating both histone and nonhistone proteins. This chapter will describe methods for the preparation and biochemical characterization of MYST family acetyltransferases, including protocols for the preparation of recombinant protein, enzyme assays for measuring steady-state parameters, and binding assays to measure cofactor and inhibitor binding. We also provide details on adapting these assays for high-throughput screening for small molecule MYST inhibitors. This chapter seeks to prepare researchers for some hurdles that they may encounter when studying the MYST proteins so that there may be better opportunity to plan appropriate controls and obtain high-quality data.


Subject(s)
Drug Evaluation, Preclinical/methods , Enzyme Assays/methods , Enzyme Inhibitors/pharmacology , Histone Acetyltransferases/antagonists & inhibitors , Histone Acetyltransferases/metabolism , Acetyl Coenzyme A/metabolism , High-Throughput Screening Assays/methods , Histone Acetyltransferases/chemistry , Humans , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism
6.
Global Spine J ; 2(4): 239-48, 2012 Dec.
Article in English | MEDLINE | ID: mdl-24353975

ABSTRACT

Bone graft substitutes have been used routinely for spine fusion for decades, yet clinical evidence establishing comparative data remains sparse. With recent scrutiny paid to the outcomes, complications, and costs associated with osteobiologics, a need to improve available data guiding efficacious use exists. We review the currently available clinical literature, studying the outcomes of various biologics in posterolateral lumbar spine fusion, and establish the need for a multicenter, independent osteobiologics registry.

7.
Health Educ Res ; 26(1): 167-77, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21123844

ABSTRACT

The Program for Arthritis Control through Education and Exercise, PACE-Ex™, is an arthritis self-management program incorporating principles and practice of self-management, goal setting and warm water exercise. The purpose of this program review is to examine the impact of PACE-Ex on participants' self-efficacy for condition management, self-management behaviors, goal achievement levels and self-reported disability, pain and health status. A retrospective review was conducted on participants who completed PACE-Ex from 1998 to 2006. A total of 347 participants completed 24 PACE-Ex programs [mean age 69.9 (±12.2) years, living with arthritis mean of 14.1 (±13.2) years]. Participants showed statistically significant improvements in their self-efficacy to manage their condition (Program for Rheumatic Independent Self-Management Questionnaire) (P < 0.001) and performance of self-management behaviors (Self-Management Behavior Questionnaire) (P < 0.01). Self-reported health status, disability and pain levels improved post-program (P < 0.01) despite reporting statistically significant increase in the total swollen and tender joint counts (Health Assessment Questionnaire) (P < 0.05). Sixty-eight percent of participants achieved or exceeded their long-term goal as measured by Goal Attainment Scaling. These findings remain to be proven with a more rigorous method yet they suggest that PACE-Ex is a promising intervention that supports healthy living for individuals with arthritis.


Subject(s)
Exercise , Osteoarthritis/therapy , Self Care/methods , Self Care/psychology , Adult , Aged , Aged, 80 and over , Female , Goals , Health Status , Humans , Male , Middle Aged , Retrospective Studies , Self Efficacy , Socioeconomic Factors
8.
J AOAC Int ; 93(2): 638-49, 2010.
Article in English | MEDLINE | ID: mdl-20480912

ABSTRACT

Two multilaboratory investigations were conducted by SUSTAIN to assess variability in the measurement of vitamin A, the marker used to verify levels of vitamin premix addition to enriched/fortified food aid products, including the widely distributed corn-soy blend (CSB). CSB specifications identify AACC Approved Method 86-06 or equivalent methods for vitamin A analysis, however there is no requirement to demonstrate equivalency. CSB samples with known and blinded levels of vitamin A and a reference standard were analyzed by 16 laboratories using their respective methods. Calculated coefficients of variation across all laboratories and methods for unknown samples and reference standard were 35 and 7.1%, respectively, suggesting the largest source of variation is the vitamin extraction procedure. Laboratories generally overestimated low levels and underestimated high levels of vitamin A within the range of 6000 and 16 000 IU/lb. Only two laboratories demonstrated excellent internal precision (+/- 300 IU vitamin A/lb) and reported values within 95% confidence interval for all blinded samples. Results of this study have implications both for quality control in food aid products (due to the use of vitamin A as a marker) and for regulatory oversight of vitamin A content in commercial food products.


Subject(s)
Food Analysis/methods , Food, Fortified/analysis , Glycine max/metabolism , Vitamin A/chemistry , Zea mays/metabolism , Chemistry Techniques, Analytical , Nutritive Value , Quality Control , Reference Standards , Reproducibility of Results , United States , United States Department of Agriculture , Vitamin A/analysis
9.
Int J Exp Pathol ; 88(3): 129-36, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17504442

ABSTRACT

Interferon-gamma (IFNgamma) is a central component of the complex cytokine and inflammatory response that contributes to liver cell injury in hepatitis. We report that in the primary hepatocyte IFNgamma synergizes with the mechanistically distinct apoptotic stimuli CD95, tumour necrosis factor-alpha (TNFalpha) and UV-irradiation. For the first time in primary hepatocytes, we show that IFNgamma-mediated apoptotic signalling requires the cell surface interaction of CD95 and its ligand, and we demonstrate that IFNgamma induces soluble CD95 ligand release from hepatocyte monolayers. Utilizing c-myc phosphorothioate antisense fragments, we suppresses hepatocyte apoptosis induced by IFNgamma. In summary, we identify apoptotic pathways that contribute to IFNgamma-mediated cell death. The hepatocellular response to IFNgamma signalling can be modulated by cytokines and by the interruption of CD95 interaction with its ligand. We present evidence to suggest that c-myc contributes to IFNgamma signalling.


Subject(s)
Hepatocytes/metabolism , Interferon-gamma/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Signal Transduction/drug effects , Animals , Apoptosis , Cells, Cultured , Enzyme-Linked Immunosorbent Assay , Fas Ligand Protein/metabolism , Hepatocytes/pathology , Interferon-gamma/pharmacology , Male , Mice , Microscopy, Fluorescence , Oligonucleotides, Antisense/pharmacology , Proto-Oncogene Proteins c-myc/genetics , Receptors, Tumor Necrosis Factor/metabolism , Staining and Labeling , Tumor Necrosis Factor-alpha/metabolism , Ultraviolet Rays/adverse effects , fas Receptor/immunology
10.
J Bone Joint Surg Br ; 88(7): 860-4, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16798985

ABSTRACT

Between June 1991 and January 1995, 42 hydroxyapatite-coated CAD-CAM femoral components were inserted in 25 patients with inflammatory polyarthropathy, 21 of whom had juvenile idiopathic arthritis. Their mean age was 21 years (11 to 35). All the patients were reviewed clinically and radiologically at one, three and five years. At the final review at a mean of 11.2 years (8 to 13) 37 hips in 23 patients were available for assessment. A total of four femoral components (9.5%) had failed, of which two were radiologically loose and two were revised. The four failed components were in patients aged 16 years or less at the time of surgery. Hydroxyapatite-coated customized femoral components give excellent medium- to long-term results in skeletally-mature young adults with inflammatory polyarthropathy. Patients aged less than 16 years at the time of surgery have a risk of 28.5% of failure of the femoral component at approximately ten years.


Subject(s)
Arthritis/surgery , Arthroplasty, Replacement, Hip/instrumentation , Biocompatible Materials , Durapatite , Femur/surgery , Adolescent , Adult , Arthritis, Juvenile/diagnostic imaging , Arthritis, Juvenile/surgery , Arthroplasty, Replacement, Hip/methods , Child , Child, Preschool , Computer-Aided Design , Female , Femur/diagnostic imaging , Hip Joint/diagnostic imaging , Hip Joint/surgery , Humans , Male , Postoperative Complications , Radiography , Treatment Outcome
11.
J Vet Med A Physiol Pathol Clin Med ; 49(7): 337-47, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12440788

ABSTRACT

The volatile anaesthetic sevoflurane is degraded to fluoride (F-) and a vinyl ether (Compound A), which have the potential to harm kidney and liver. Whether renal and hepatic injuries can occur in horses is unknown. Cardiopulmonary, biochemical and histopathological changes were studied in six healthy thoroughbred horses undergoing 18 h of low-flow sevoflurane anaesthesia. Serum F- concentrations were measured and clinical laboratory tests performed to assess hepatic and renal function before and during anaesthesia. Necropsy specimens of kidney and liver were harvested for microscopic examination and compared to pre-experimental needle biopsies. Cardiopulmonary parameters were maintained at clinically acceptable levels throughout anaesthesia. Immediately after initiation of sevoflurane inhalation, serum F- levels began to rise, reaching an ongoing 38-45 micromol 1(-1) plateau at 8 h of anaesthesia. Serum biochemical analysis revealed only mild increases in glucose and creatinine kinase and a decrease in total calcium. Beyond 10 h of anaesthesia mild, time-related changes in urine included increased volume, glucosuria and enzymuria. Histological examination revealed mild microscopic changes in the kidney involving mainly the distal tubule, but no remarkable alterations in liver tissue. These results indicate that horses can be maintained in a systemically healthy state during unusually prolonged sevoflurane anaesthesia with minimal risk of hepatocellular damage from this anaesthetic. Furthermore, changes in renal function and morphology observed after sevoflurane inhalation are judged minimal and appear to be clinically irrelevant; they may be the result of anaesthetic duration, physiological stressors, sevoflurane (or its degradation products) or other unkown factors associated with these animals and study conditions.


Subject(s)
Anesthetics, Inhalation/pharmacokinetics , Fluorides/blood , Horses/physiology , Kidney/metabolism , Liver/metabolism , Methyl Ethers/pharmacokinetics , Anesthetics, Inhalation/blood , Anesthetics, Inhalation/urine , Animals , Blood Gas Analysis/veterinary , Hemodynamics , Horses/blood , Horses/urine , Methyl Ethers/blood , Methyl Ethers/urine , Oximetry/veterinary , Respiration, Artificial/veterinary , Sevoflurane , Time Factors
12.
Clin Nephrol ; 57(1): 27-37, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11837799

ABSTRACT

BACKGROUND: As the incidence of diabetic nephropathy increases, especially in minority populations, more simultaneous pancreas-kidney (SPK) transplants are being performed both in the United States and worldwide. The role of matching on SPK outcomes and organ allocation remains controversial. The purpose of this analysis was to determine the influence of HLA matching using currently employed criteria on 5-year SPK graft survival. METHODS: We performed an analysis of all 3,316 SPK transplants performed in the United States reported to the United Network for Organ Sharing (UNOS) between December 31, 1988 and December 31, 1994. Kaplan-Meier unadjusted 1- and 5-year graft survival with log rank comparisons and Cox multivariable regression models that adjusted for 12 confounding variables were used to analyze the influence of HLA matching on outcomes. RESULTS: Despite low-grade HLA or DR matching or high levels of common reactive groups (CREG) mismatching, 1- and 5-year allograft survival rates were 90% and 78% for kidney, and 85% and 75% for pancreas transplantation. CONCLUSIONS: SPK transplantation is associated with excellent outcomes independent of the level of HLA matching. These data support the hypothesis that SPK transplants need not be allocated based on matching criteria, thus minimizing organ ischemia time and promoting a more racially equitable allocation for SPKs in the US today.


Subject(s)
Graft Survival/immunology , Histocompatibility Testing/methods , Kidney Transplantation/immunology , Pancreas Transplantation/immunology , Adult , Cohort Studies , Diabetes Mellitus, Type 1/surgery , Female , HLA Antigens/immunology , Humans , Kidney Transplantation/statistics & numerical data , Male , Minority Groups , Multivariate Analysis , Pancreas Transplantation/statistics & numerical data , Proportional Hazards Models , Registries , Survival Rate , Treatment Outcome , United States
13.
Thorax ; 56(12): 916-23, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11713353

ABSTRACT

BACKGROUND: Clearance of inhaled technetium 99m-labelled diethylenetriamine penta-acetic acid ((99m)Tc-DTPA) from the lungs is a potential indicator of disease progression in patients with idiopathic pulmonary fibrosis (IPF). METHODS: We prospectively analysed the usefulness of this technique for predicting survival in 106 non-smoking patients with usual interstitial pneumonia (UIP) pattern IPF diagnosed by high resolution CT (HRCT) scanning or histological examination (M/F 65/41, mean (SD) age 61 (11) years). DTPA clearance was analysed according to both mono-exponential and bi-exponential models. Half times for the fast (t(0.5)F) and slow (t(0.5)S) components of clearance, the percentage contribution of the fast component (fF), and half time for mono-exponential approximation to the early part of the clearance curve (t(0.5)) were calculated. RESULTS: The patients had substantially faster t(0.5) (mean 23.9 (9.6) minutes) than normal values (>45 minutes). Thirty seven patients (35%) died during follow up (median 15 months). Univariate Cox regression analysis identified significant predictors of survival as age, forced expiratory volume in 1 second (FEV(1)), forced vital capacity (FVC), total lung capacity (TLC), % predicted TLC, carbon monoxide transfer factor (TLCO), % predicted TLCO, arterial oxygen tension (PaO(2)), oxygen saturation, t(0.5)F, and HRCT fibrosis score. Multiple stepwise Cox regression analysis identified t(0.5)F (p=0.03, hazard ratio 0.747, 95% CI 0.578 to 0.964), % predicted TLC (p=0.02, hazard ratio 0.976, 95% CI 0.956 to 0.995), % predicted TLCO (p=0.003, hazard ratio 0.960, 95% CI 0.935 to 0.986), and age (p=0.003, hazard ratio 1.062, 95% CI 1.021 to 1.104) as independent predictors of survival. CONCLUSION: These data suggest that (99m)Tc-DTPA clearance t(0.5)F measurement may predict survival in patients with UIP pattern IPF.


Subject(s)
Pulmonary Fibrosis/metabolism , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Pentetate/pharmacokinetics , Aged , Bronchoalveolar Lavage Fluid/cytology , Female , Humans , Male , Metabolic Clearance Rate , Middle Aged , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Prospective Studies , Regression Analysis , Respiratory Function Tests , Survival Analysis
14.
Transplantation ; 71(6): 767-72, 2001 Mar 27.
Article in English | MEDLINE | ID: mdl-11330540

ABSTRACT

BACKGROUND: Hepatic artery thrombosis (HAT) is a significant cause of morbidity after liver transplantation. The aims of this study are to identify and compare risk factors that might contribute to HAT. METHODS: A total of 424 liver transplants performed at the University of Virginia were reviewed. HAT was defined as complete disruption of arterial blood flow to the allograft and was identified in 29 cases (6.8%). HAT was classified as early (less than 1 month posttransplant, 9 cases: 2.1%) or late (more than 1 month posttransplant, 20 cases: 5.4%). Possible risk factors for HAT were analyzed using Pearson chi2 test for univariate analysis and logistic regression for multivariate analysis. RESULTS: Multiple transplants, recipient/donor weight ratio >1.25, biopsy-proven rejection within 1 week of transplant, recipient negative cytomegalovirus (CMV) status, arterial anastomosis to an old conduit (defined as a previously constructed aorto-hepatic artery remnant using donor iliac artery), and CMV negative patients receiving allograft from CMV positive donors were found to be significant risk factors for developing early HAT. After logistic regression, factors independently predicting early HAT included arterial anastomosis to an old conduit [odds ratio (OR)=7.33], recipient/donor weight ratio >1.25 (OR=5.65), biopsy-proven rejection within 1 week posttransplant (OR=2.81), and donor positive and recipient negative CMV status (OR=2.66). Female donor, the combination of female donor and male recipient, recipient hepatitis C-related liver disease, donor negative CMV status, and the combination of recipient CMV negative and donor CMV negative were found to be significant risk factors for late HAT. Factors independently predicting late HAT by logistic regression included negative recipient and donor CMV status (OR=2.26) and the combination of a female donor and male recipient (OR=1.97). CONCLUSION: Therefore, in nonemergency situations attention to these factors in donor allocation may minimize the possibility of HAT.


Subject(s)
Arterial Occlusive Diseases/epidemiology , Hepatic Artery , Liver Transplantation/adverse effects , Adult , Child , Child, Preschool , Female , Humans , Logistic Models , Male , Multivariate Analysis , Risk Factors , Time Factors
15.
J Hand Surg Br ; 25(2): 223-4, 2000 Apr.
Article in English | MEDLINE | ID: mdl-11062587

ABSTRACT

Fibrodysplasia ossificans progressiva is a rare disorder characterized by the progressive development of heterotopic bone in the connective tissues of skeletal muscle, ligaments and tendons. Surgical trauma is one of the most potent stimuli for ossification and surgical treatment is generally considered to be contraindicated in this condition. We report a good functional result in a patient with severe hand disability secondary to an ulna-carpal bar in fibrodysplasia ossificans progressiva.


Subject(s)
Arthrodesis , Myositis Ossificans/surgery , Ulna/surgery , Wrist/surgery , Adult , Humans , Male
16.
Clin Transplant ; 14(4 Pt 2): 386-90, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10946776

ABSTRACT

Historically, age has been considered to be a relative contraindication for organ donors. The use of elderly donors for liver transplantation remains controversial due to the fear of inferior outcome. According to United Network for Organ Sharing (UNOS) data, the proportion of older donors has been increasing annually. This study describes the short- and long-term outcomes for transplantation of elderly donor livers. Three hundred and seventy-four primary liver transplantations, which had been performed at the University of Virginia Health System from 7 February 1988 to 31 December 1998, were included. Graft survival, incidence of primary non-function, and hepatic artery thrombosis (HAT) after transplantation according to the different age groups of liver donors were analyzed. Cases were analyzed by donor age (group I, n = 106: aged < 20 yr; group II, n = 217: aged between 20 and 49 yr; group III, n = 51: aged > or =50 yr), and by donor age in comparison with recipient age (group IV, n = 65: recipients transplanted with organs from donors within 5 yr of their age; group V, n = 266: recipients from donors > 5 yr younger than their age; group VI, n = 43: recipients from donors > 5 yr older than their age). Group III or VI (group of advanced donor age) and group II or V (control group) were compared by age, gender, race, body weight, height, pre-transplantation cytomegalovirus (CMV) status of the recipients donors, cause of brain death of donors, total or warm ischemic time, ABO matching, and degree of human leucocyte antigen (HLA) mismatching. No significant difference in 5 yr graft survival was found between the groups by donor age (p = 0.604) and by donor age compared with recipient age (p = 0.567). Moreover, no significant differences in the incidence of primary non-function and HAT after transplantation were found between the groups by donor age and by donor age compared with recipient age. Older donors were more likely to be women and to have antibodies to CMV, as well as to have died by cerebrovascular causes. Race, body weight, height of both recipients and donors, total or warm ischemic time of grafts, ABO matching, and degree of HLA mismatching were not significantly different between the groups. We conclude from this study that advanced donor age is not a contraindication to liver transplantation if careful assessment of donors is made on a case-by-case basis. There is a need to maintain an open mind with regard to the use of livers from older donors due to the current situation of serious organ shortages.


Subject(s)
Liver Transplantation , Tissue Donors , Adult , Age Factors , Female , Humans , Male , Middle Aged , Treatment Outcome
17.
J Acoust Soc Am ; 108(2): 574-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10955622

ABSTRACT

The five independent second-order elastic constants of a transversely isotropic aluminum/alumina fiber composite have been measured for the first time using a resonant ultrasound spectroscopy technique. These data were used to deduce the elastic constants and engineering moduli for off-axis loading conditions.

19.
Toxicol Pathol ; 28(3): 482-99, 2000.
Article in English | MEDLINE | ID: mdl-10862569

ABSTRACT

Advances in genetic engineering have created opportunities for improved understanding of the molecular basis of carcinogenesis. Through selective introduction, activation, and inactivation of specific genes, investigators can produce mice of unique genotypes and phenotypes that afford insights into the events and mechanisms responsible for tumor formation. It has been suggested that such animals might be used for routine testing of chemicals to determine their carcinogenic potential because the animals may be mechanistically relevant for understanding and predicting the human response to exposure to the chemical being tested. Before transgenic and knockout mice can be used as an adjunct or alternative to the conventional 2-year rodent bioassay, information related to the animal line to be used, study design, and data analysis and interpretation must be carefully considered. Here, we identify and review such information relative to Tg.AC and rasH2 transgenic mice and p53+/- and XPA-/- knockout mice, all of which have been proposed for use in chemical carcinogenicity testing. In addition, the implications of findings of tumors in transgenic and knockout animals when exposed to chemicals is discussed in the context of human health risk assessment.


Subject(s)
Animals, Genetically Modified , Carcinogenicity Tests/methods , Carcinogens/toxicity , Neoplasms, Experimental/chemically induced , Toxicology/methods , Animals , Female , Gene Targeting , Male , Mice , Mice, Knockout , Neoplasms, Experimental/genetics , Rats , Risk Assessment
20.
Biomed Instrum Technol ; 34(3): 185-95, 2000.
Article in English | MEDLINE | ID: mdl-10868260

ABSTRACT

A variety of business systems, clinical work systems, instrumentation systems, information systems, infrastructure systems, and management systems interact to make the modern healthcare facility work. The key to designing for such a system is systems engineering, a skill often little appreciated among clinical engineers. At the heart of systems engineering is requirements engineering and management (REAM), which is defined as "the process of discovering, documenting and managing systems requirements." The principal activities of REAM include eliciting, understanding, negotiating, describing, validating, and managing system requirements. When REAM is done improperly, the resulting system will be satisfactory only if chance intervenes. Well-done REAM is likely to bring the project in on time, under budget, and at full performance.


Subject(s)
Biomedical Engineering/methods , Biomedical Engineering/economics , Biomedical Engineering/instrumentation , Biomedical Engineering/organization & administration , Computer Systems , Costs and Cost Analysis , Documentation , Equipment Design , Health Facility Administration , Humans , Information Systems/economics , Information Systems/instrumentation , Information Systems/organization & administration , Medical Laboratory Science/economics , Medical Laboratory Science/instrumentation , Medical Laboratory Science/methods , Medical Laboratory Science/organization & administration , Systems Integration
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