Showing papers by "Exponent published in 2012"
TL;DR: The patient and clinical factors influencing the economic burden of periprosthetic joint infection (PJI) in the United States are characterized and the annual cost of infected revisions to US hospitals increased from $320 million to $566 million during the study period and was projected to exceed $1.62 billion by 2020.
Abstract: This study characterizes the patient and clinical factors influencing the economic burden of periprosthetic joint infection (PJI) in the United States. The 2001-2009 Nationwide Inpatient Sample was used to identify total hip and knee arthroplasties using International Classification of Diseases, Ninth Revision, procedure codes. The relative incidence of PJI ranged between 2.0% and 2.4% of total hip arthroplasties and total knee arthroplasties and increased over time. The mean cost to treat hip PJIs was $5965 greater than the mean cost for knee PJIs. The annual cost of infected revisions to US hospitals increased from $320 million to $566 million during the study period and was projected to exceed $1.62 billion by 2020. As the demand for joint arthroplasty is expected to increase substantially over the coming decade, so too will the economic burden of prosthetic infections.
1,369 citations
TL;DR: All seven investigated prognostic factors showed a modest but significant predictive relationship with survival, and certain prognostic Factors may prove useful in determining optimal therapeutic options.
Abstract: The overall median survival following CLM liver resection was 3.6 years. All seven investigated prognostic factors showed a modest but significant predictive relationship with survival, and certain prognostic factors may prove useful in determining optimal therapeutic options. Due to the increasing complexity of surgical interventions for CLM and the inclusion of patients with higher disease burdens, future studies should consider the potential for selection and referral bias on survival.
491 citations
TL;DR: Specific patient comorbidities that were independently associated with an increased risk of periprosthetic joint infection and of ninety-day postoperative mortality in Medicare patients who had undergone total hip arthroplasty are identified.
Abstract: Background: The patient-related risk factors for periprosthetic joint infection and postoperative mortality in elderly patients undergoing total hip arthroplasty are poorly understood. The purpose of this study was to identify the specific patient comorbidities that are associated with an increased risk of periprosthetic joint infection and of ninety-day postoperative mortality in U.S. Medicare patients undergoing total hip arthroplasty.
Methods: The Medicare 5% sample claims database was used to calculate the relative risk of periprosthetic joint infection and of ninety-day postoperative mortality as a function of preexisting comorbidities in 40,919 patients who underwent primary total hip arthroplasty between 1998 and 2007. The impact of twenty-nine comorbid conditions on periprosthetic joint infection and on postoperative mortality was examined with use of Cox regression, controlling for age, sex, census region, public assistance, and all other baseline comorbidities. The adjusted hazard ratios for all comorbid conditions were evaluated, and the Wald chi-square statistic was used to rank the degree of association of each condition with periprosthetic joint infection and with postoperative mortality. The Bonferroni-Holm method was used to adjust for the multiple comparisons resulting from the number of comorbid conditions analyzed.
Results: Comorbid conditions associated with an increased adjusted risk of periprosthetic joint infection (in decreasing order of significance, p < 0.05 for all comparisons) were rheumatologic disease (hazard ratio [HR] = 1.71), obesity (HR = 1.73), coagulopathy (HR = 1.58), and preoperative anemia (HR = 1.36). Comorbid conditions associated with an increased adjusted risk of ninety-day postoperative mortality (in decreasing order of significance, p < 0.05 for all comparisons) were congestive heart failure (HR = 2.11), metastatic cancer (HR = 3.14), psychosis (HR = 1.85), renal disease (HR = 1.98), dementia (HR = 2.04), hemiplegia or paraplegia (HR = 2.62), cerebrovascular disease (HR = 1.40), and chronic pulmonary disease (HR = 1.32).
Conclusions: We identified specific patient comorbidities that were independently associated with an increased risk of periprosthetic joint infection and of ninety-day postoperative mortality in Medicare patients who had undergone total hip arthroplasty. This information is important when counseling elderly patients regarding the risks of periprosthetic joint infection and mortality following total hip arthroplasty, as well as for risk adjustment of publicly reported total hip arthroplasty outcomes.
Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
416 citations
TL;DR: There is a steady growth in the use of permanent pacemakers in the United States, although DDD device use is increasing, whereas single-chamber ventricular pacemaker use is decreasing.
395 citations
TL;DR: This information is important when counseling elderly patients regarding the risks of mortality and PJI after TKA and risk-adjusting publicly reported TKA patient outcomes.
Abstract: Background
The impact of specific baseline comorbid conditions on the relative risk of postoperative mortality and periprosthetic joint infection (PJI) in elderly patients undergoing TKA has not been well defined.
338 citations
TL;DR: Only a few of the proposed ECG recognition algorithms appear to be able to support performance improvement due to multiple training sessions, and only three of these algorithms produced equal error rates (EERs) in the single digits, including an EER of 5.5% using a method proposed by us.
Abstract: The electrocardiogram (ECG) is an emerging biometric modality that has seen about 13 years of development in peer-reviewed literature, and as such deserves a systematic review and discussion of the associated methods and findings. In this paper, we review most of the techniques that have been applied to the use of the electrocardiogram for biometric recognition. In particular, we categorize the methodologies based on the features and the classification schemes. Finally, a comparative analysis of the authentication performance of a few of the ECG biometric systems is presented, using our inhouse database. The comparative study includes the cases where training and testing data come from the same and different sessions (days). The authentication results show that most of the algorithms that have been proposed for ECG-based biometrics perform well when the training and testing data come from the same session. However, when training and testing data come from different sessions, a performance degradation occurs. Multiple training sessions were incorporated to diminish the loss in performance. That notwithstanding, only a few of the proposed ECG recognition algorithms appear to be able to support performance improvement due to multiple training sessions. Only three of these algorithms produced equal error rates (EERs) in the single digits, including an EER of 5.5% using a method proposed by us.
321 citations
TL;DR: A critical review of the animal toxicology literature of nitrite indicates that in the absence of co-administration of a carcinogenic nitrosamine precursor, there is no evidence for carcinogenesis and this new and growing body of evidence calls for a reconsideration of nitrites and nitrate safety.
264 citations
TL;DR: The available literature shows no solid evidence linking glyphosate exposure to adverse developmental or reproductive effects at environmentally realistic exposure concentrations, and suggests that such effects were due to surfactants present in the formulations and not the direct result of glyphosate exposure.
Abstract: Glyphosate is the active ingredient of several widely used herbicide formulations. Glyphosate targets the shikimate metabolic pathway, which is found in plants but not in animals. Despite the relative safety of glyphosate, various adverse developmental and reproductive problems have been alleged as a result of exposure in humans and animals. To assess the developmental and reproductive safety of glyphosate, an analysis of the available literature was conducted. Epidemiological and animal reports, as well as studies on mechanisms of action related to possible developmental and reproductive effects of glyphosate, were reviewed. An evaluation of this database found no consistent effects of glyphosate exposure on reproductive health or the developing offspring. Furthermore, no plausible mechanisms of action for such effects were elucidated. Although toxicity was observed in studies that used glyphosate-based formulations, the data strongly suggest that such effects were due to surfactants present in the formulations and not the direct result of glyphosate exposure. To estimate potential human exposure concentrations to glyphosate as a result of working directly with the herbicide, available biomonitoring data were examined. These data demonstrated extremely low human exposures as a result of normal application practices. Furthermore, the estimated exposure concentrations in humans are >500-fold less than the oral reference dose for glyphosate of 2 mg/kg/d set by the U.S. Environmental Protection Agency (U.S. EPA 1993). In conclusion, the available literature shows no solid evidence linking glyphosate exposure to adverse developmental or reproductive effects at environmentally realistic exposure concentrations.
133 citations
TL;DR: The high incidence of infection following instrumented lumbar fusion warrants increased focus on infection risk mitigation, especially for patients with comorbid conditions.
Abstract: Object This retrospective analysis of Medicare administrative data was performed to evaluate the risk of infection following instrumented lumbar fusion over a 10-year follow-up period in the Medicare population. Although infection can be a devastating complication, due to its rarity it is difficult to characterize infection risk except in large patient populations. Methods Using ICD-9-CM and CPT4 procedure codes, the Medicare 5% analytical research files for inpatient, outpatient, and physician carrier claims were checked to identify patients who were treated between 1997 and 2009 with lumbar spine fusion in which cages or posterior instrumentation were used. Patients younger than 65 years old were excluded. Patients were followed continuously by using the matching denominator file until they withdrew from Medicare or died. The authors identified 15,069 patients with primary fusion procedures and 605 with revision of instrumented lumbar fusion. Infections were identified by the related ICD-9 codes (998.59...
126 citations
TL;DR: A specific soil particle size of <150 μm is recommended for future studies on the oral bioavailability and bioaccessibility of PAHs in soil.
Abstract: Over the last 30 years, there has been extensive research designed to quantify the extent of oral bioavailability and bioaccessibility of organic and inorganic contaminants in soil. One aspect of this research is the soil particle size selected to represent environmental exposures, which may affect study results and comparability across studies. Different research groups have studied soil particle sizes ranging from <45 μm to <2000 μm. This article reviews the historical and technical considerations that pertain to the selection of an appropriate particle size fraction for evaluating the relative oral bioavailability of chemicals from soil, which include (1) how the resultant data will be used in human health risk assessment, (2) soil fractions historically used in oral bioavailability studies, (3) studies of soil adherence to human hands, (4) the distribution of contaminants in soils as a function of particle size, and (5) the effect of differential bioavailability as a function of soil particle size and geochemical matrix. These factors are first discussed from a general perspective, applicable to all contaminants in soil, and then more specifically for polycyclic aromatic hydrocarbons (PAHs) in soil. Based on this review, a specific soil particle size of <150 μm is recommended for future studies on the oral bioavailability and bioaccessibility of PAHs in soil.
109 citations
TL;DR: Makris et al. as mentioned in this paper stated that these in vivo tests are unsuitable for screening large numbers of chemicals for many reasons including low throughput, high cost, and questions regarding reliability.
Abstract: test Guidelines OPPtS 8706300 on DNt (US ePA, 1998) and in 2007 the Organization for economic Cooperation and Development (OeCD) endorsed a new OeCD DNt test Guideline 426 (OeCD, 2007). these guidelines are largely based on animal studies and are used as higher tiered, triggered tests based on structure activity relationships or evidence of neurotoxicity in standard adult, developmental, or reproduction studies (Makris et al., 2009). experts at the conference stated that these in vivo tests are unsuitable for screening large numbers of chemicals for many reasons including low throughput, high cost, and questions regarding reliability. there was also consensus that new, reliable, and efficient screening and assessment tools are needed for better identification, prioritization, and evaluation of chemicals with the potential to induce developmental neurotoxicity. the information obtained from these screening studies will likely also help to refine animal tests and to inform epidemiological studies.
TL;DR: It is demonstrated that negative immune-related effects of not breastfeeding and cesarean delivery can be mitigated by including Bb12 in infant formula, thereby providing infants a safe, dietary, immune-modulating bacterial introduction.
Abstract: Background: Addition of probiotics to infant formula may positively affect immune function in nonexclusively breastfed infants. This study aimed to investigate the effect of infant starter formula containing the probiotic Bifidobacterium animalis subspecies lactis (Bb12) on intestinal immunity and inflammation. Methods: Six-week-old healthy, full-term infants (n = 172) were enrolled in a prospective, randomized, double-blind, controlled clinical trial with 2 groups studied in parallel to a breastfed comparison group. Formula-fed (FF) infants were randomized to partially hydrolyzed whey formula (CON) or the same formula containing 106 colony-forming units (CFU) Bb12/g (PRO) for 6 weeks. Fecal secretory IgA (sIgA), calprotectin, lactate, and stool pH were assessed at baseline, 2 weeks, and 6 weeks. Anti-poliovirus-specific IgA and anti-rotavirus-specific IgA were assessed at 2 and 6 weeks. Results: Among vaginally delivered FF infants, PRO consumption increased (P < .05) fecal sIgA compared to CON. Anti-pol...
TL;DR: Energy-adjusted intakes of carotenoids and flavonoids are higher among men and women whose diets conform to dietary guidance for fruits and vegetables, and a limited number of foods provide the majority of these phytonutrients.
TL;DR: In this article, the presence of synergistic effects in ternary cementitious systems containing portland cement (OPC), class C fly ash (FA) and silica fume (SF) was verified.
Abstract: This research was primarily conducted to verify the presence of synergistic effects in ternary cementitious systems containing portland cement (OPC), class C fly ash (FA) and silica fume (SF). A subsequent objective of the study was to quantify the magnitude of the synergy and to determine its source. For a ternary mixture containing 20% FA and 5% SF by mass, the synergistic effect was observed mostly at later ages (7 days onward) and it resulted in an increased compressive strength and resistance to chloride ion penetration as well as a reduced rate of water absorption (sorptivity) compared to predictions based on individual effects of FA and SF in respective binary systems. The observed synergy was attributed to both chemical and physical effects. The chemical effect manifested itself in the form of an increased amount of hydration products. The physical effect associated with packing density was, somewhat contrary to general belief, not due to an optimized particle size distribution of the binder components of the ternary cementitious system. Instead, it was the result of smaller initial inter-particle spacing caused by lower specific gravities of both FA and SF which, in turn, led to a lower volumetric w/cm. If the mixture design was adjusted to account for these differences, the physical effect would be diminished.
TL;DR: A thermal analysis conducted to assess the feasibility of exploring lunar cold traps and the basic design principles of these rovers are described and the efforts to implement the key features of the Axel concept are reviewed.
Abstract: Some of the most appealing science targets for future exploration missions in our solar system lie in terrains that are inaccessible to state-of-the-art rover technology This paper discusses the challenges and constraints of designing a robotic explorer for these “extreme'' terrains and then examines the trade-offs among different mobility architectures To address many of these challenges, we have developed the Axel family of rovers The Axel rover is a two-wheeled tethered robot capable of rappelling down steep slopes and traversing rocky terrain The DuAxel rover, which is a four-wheeled vehicle formed from two Axel rovers, provides untethered mobility to get to extreme terrains We describe the basic design principles of these rovers and review our efforts to implement the key features of the Axel concept Limitations found during experiments with prior Axel rover prototypes led to the design of a third-generation Axel rover We describe the features of this new rover and then present a thermal analysis conducted to assess the feasibility of exploring lunar cold traps, which are expected to have a temperature range of 40 to 70 K We conclude the paper with results showcasing Axel and DuAxel's extreme-terrain performance as evaluated during two recent field tests in a steeply sloped Southern California rock quarry and at a location in Arizona that closely resembles rugged Martian terrain We also summarize lessons learned during the Axel development program © 2012 Wiley Periodicals, Inc © 2012 Wiley Periodicals, Inc
TL;DR: The rodent is not considered the most appropriate model for human placental transfer of Fc-containing biopharmaceuticals because it is currently believed to overestimate exposure during organogenesis, but the rodent may provide a conservative approach for hazard identification.
Abstract: Anatomical and developmental differences of the parental–offspring interface among experimental animals and humans throughout gestation are reviewed focusing on biodistribution of immunoglobulins (IgG). The formation of the extraembryonic membranes, uteroplacental circulation, and characteristics of the placenta (gross shape, modes of implantation, surface modifications that increase surface area, and extent of embryonic invasion into maternal tissue) are reviewed. Placental physiology and function are covered with attention to transfer of xenobiotics. Placental transfer of immunoglobulins in the human, non-human primate (NHP), rodent, and rabbit is discussed and the transfer of human fragment crystallizable (Fc)-containing biopharmaceuticals and potential impact on developmental toxicity risk assessment are specifically addressed. Safety assessment is often limited to the NHP as the only pharmacologically relevant model, despite poor statistical power as employed in current experimental designs. Although...
TL;DR: Based on current dietary guidance to consume as little industrial TFA as possible, much progress is needed to attain this goal, including food industry efforts to remove TFA from the food supply and educating the public about making healthy food choices.
Abstract: Because of efforts to decrease trans fatty acids (TFA) in the food supply, intake should be assessed in the population to establish a baseline TFA intake. The 1999–2002 National Health and Nutrition Examination Survey (NHANES) was used to identify a benchmark for TFA intake. TFA was estimated by mean, median, and quintile of intake, TFA intake data were weighted using the NHANES 4-year sample weights. The main outcome measures included TFA intake in grams per day and percentage of energy in the top 25 food sources of TFA. Data are reported for 16,669 individuals ≥3 years of age. Median TFA intake was 2.3 % of calories (5 g/day) with 0.9–4.5 % of energy (1.5–13.1 g/day) over different quintiles of intake. Mean TFA intake was 2.5 % of energy (6.1 g/day). The range of TFA intake in the fifth quintile was very large, i.e., 3.5–12.5 % of energy or 8.8–92.4 g/day. Increasing quintiles of TFA intake were associated with increases in total fat (26.7–37.6 % of energy), saturated fat (7.6–10.5 % of energy), and calories (for those >20 years of age: 2,416–2,583 for men and 1,679–1,886 for women). Major food sources of dietary TFA were cakes, cookies, pies, and pastries. Based on current dietary guidance to consume as little industrial TFA as possible, much progress is needed to attain this goal, including food industry efforts to remove TFA from the food supply and educating the public about making healthy food choices.
TL;DR: An analysis of the potential number of cancer cases that might be prevented if half the U.S. population increased its fruit and vegetable consumption by one serving each per day provides confidence that consumers should not be concerned about cancer risks from consuming conventionally-grown fruits and vegetables.
TL;DR: It is suggested that individuals with LBP use a strategy of trunk stiffening achieved through co-activation of trunk musculature, aided by enhanced distal responses, to respond to unexpected support surface perturbations.
TL;DR: This work compared the oxidation, in vitro strength, fatigue-crack propagation resistance, and wear of highly cross-linked UHMWPE doped with vitamin E to γ-inert-sterilized direct compression-molded UH MWPE (control) and found that the vitamin E-stabilized material exhibited 73% to 86% reduction in wear for both cruciate-retaining and posterior-st stabilized total knee arthroplasty designs.
Abstract: Concerns about reduced strength, fatigue resistance, and oxidative stability of highly cross-linked and remelted ultrahigh-molecular-weight polyethylene (UHMWPE) have limited its clinical acceptance for total knee arthroplasty. We hypothesized that a highly cross-linked UHMWPE stabilized with vitamin E would have less oxidation and loss of mechanical properties. We compared the oxidation, in vitro strength, fatigue-crack propagation resistance, and wear of highly cross-linked UHMWPE doped with vitamin E to γ-inert-sterilized direct compression-molded UHMWPE (control). After accelerated aging, the control material showed elevated oxidation, loss of small-punch mechanical properties, and loss of fatigue-crack propagation resistance. In contrast, the vitamin E-stabilized material had minimal changes and exhibited 73% to 86% reduction in wear for both cruciate-retaining and posterior-stabilized total knee arthroplasty designs. Highly cross-linked vitamin E-stabilized UHMWPE performed well in vitro.
TL;DR: No consistent pattern of positive associations indicating a causal relationship between total cancer (in adults or children) or any site-specific cancer and exposure to glyphosate is found.
01 Jan 2012
TL;DR: This chapter reviews basic information about polymers in general and describes the structure and composition of PEEK, a member of the polyaryletherketone polymer (PAEK) family that has been used for orthopedic and spinal implants.
Abstract: Publisher Summary This chapter reviews basic information about polymers in general and describes the structure and composition of polyaryletheretherketone (PEEK). It is a member of the polyaryletherketone polymer (PAEK) family that has been used for orthopedic and spinal implants. Historically, the availability of PEEK arrived at a time when there was a growing interest in the development of “isoelastic” hip stems and fracture fixation plates, with stiffnesses comparable with the bone. Much of the research on PEEK implants has been fragmented in the materials science, composites, biomaterials, and application-specific literature. PEEK had emerged as the leading high-performance thermoplastic candidate for replacing metal implant components, especially in orthopedics and trauma. Numerous studies have documented the successful clinical performance of PAEKs in orthopedic and spine patients. Recent research has also investigated the biotribology of PEEK composites as bearing materials and flexible implants used for joint arthroplasty. Because of the interest in further improving implant fixation, PEEK biomaterials research has also focused on compatibility of the polymer with bioactive materials, including hydroxyapatite, either as a composite filler or as a surface coating. As a result of ongoing biomaterials research, PEEK and related composites can be engineered today with a wide range of physical, mechanical, and surface properties, depending upon their implant application.
TL;DR: Rim damage was the predominant cause of polyethylene wear in 7 specimens retrieved at revision arthroplasty and direct contact between the humeral component and inferior metaglene screws is concerning because this could lead to accelerated ultra-highmolecular weight poly methylene wear and also induce mechanical loosening of the glenoid component.
TL;DR: A novel acellular bone-graft-free endogenous repair therapy for orthotopic tissue-engineered bone regeneration is presented.
Abstract: Biomaterial scaffolds functionalized to stimulate endogenous repair mechanisms via the incorporation of osteogenic cues offer a potential alternative to bone grafting for the treatment of large bone defects. We first quantified the ability of a self-complementary adeno-associated viral vector encoding bone morphogenetic protein 2 (scAAV2.5-BMP2) to enhance human stem cell osteogenic differentiation in vitro. In two-dimensional culture, scAAV2.5-BMP2-transduced human mesenchymal stem cells (hMSCs) displayed significant increases in BMP2 production and alkaline phosphatase activity compared with controls. hMSCs and human amniotic-fluid-derived stem cells (hAFS cells) seeded on scAAV2.5-BMP2-coated three-dimensional porous polymer Poly(e-caprolactone) (PCL) scaffolds also displayed significant increases in BMP2 production compared with controls during 12 weeks of culture, although only hMSC-seeded scaffolds displayed significantly increased mineral formation. PCL scaffolds coated with scAAV2.5-BMP2 were implanted into critically sized immunocompromised rat femoral defects, both with or without pre-seeding of hMSCs, representing ex vivo and in vivo gene therapy treatments, respectively. After 12 weeks, defects treated with acellular scAAV2.5-BMP2-coated scaffolds displayed increased bony bridging and had significantly higher bone ingrowth and mechanical properties compared with controls, whereas defects treated with scAAV2.5-BMP2 scaffolds pre-seeded with hMSCs failed to display significant differences relative to controls. When pooled, defect treatment with scAAV2.5-BMP2-coated scaffolds, both with or without inclusion of pre-seeded hMSCs, led to significant increases in defect mineral formation at all time points and increased mechanical properties compared with controls. This study thus presents a novel acellular bone-graft-free endogenous repair therapy for orthotopic tissue-engineered bone regeneration.
TL;DR: The Deer Track Bioreactor Experiment (DTBE) as discussed by the authors was a field-scale experiment conducted in a drainage lysimeter (8.2m height, 2.4m diameter) to assess the physical, chemical, and biological response of municipal solid waste with leachate addition.
Abstract: The Deer Track Bioreactor Experiment (DTBE) was a field-scale experiment conducted in a drainage lysimeter (8.2-m height, 2.4-m diameter) to assess the physical, chemical, and biological response of municipal solid waste with leachate addition. The experiment was operated for 1,067 days, with leachate dosing initiated on Day 399. Fresh leachate collected from a full-scale landfill was used for each dose. The ratio of cumulative leachate effluent to influent volume increased during dosing and leveled off at approximately 80%, indicating field capacity was achieved. Peak Darcy flux ranged from 2×10-7 m/s to 4×10-5 m/s, with larger flux computed for the last four doses when waste saturation was higher. During the experiment, the average dry unit weight of the waste increased 28% and the dry-weight water content (wd) increased 18%; field capacity of the waste was 44 to 48% on a dry-weight basis. Biochemical methane potential decreased from 51.4 to 3.4 mL-CH4/g-dry, indicating that 93% of the potent...
TL;DR: There was insufficient evidence that human developmental exposures to CPF produce adverse neurobehavioral effects in infants and children across different cohort studies that may be relevant toCPF exposure.
Abstract: Developmental neurobehavioral outcomes attributed to exposure to chlorpyrifos (CPF) obtained from epidemiologic and animal studies published before June 2010 were reviewed for risk assessment purposes. For epidemiological studies, this review considered (1) overall strength of study design, (2) specificity of CPF exposure biomarkers, (3) potential for bias, and (4) Hill guidelines for causal inference. In the case of animal studies, this review focused on evaluating the consistency of outcomes for developmental neurobehavioral endpoints from in vivo mammalian studies that exposed dams and/or offspring to CPF prior to weaning. Developmental neuropharmacologic and neuropathologic outcomes were also evaluated. Experimental design and methods were examined as part of the weight of evidence. There was insufficient evidence that human developmental exposures to CPF produce adverse neurobehavioral effects in infants and children across different cohort studies that may be relevant to CPF exposure. In animals, few behavioral parameters were affected following gestational exposures to 1 mg/kg-d but were not consistently reported by different laboratories. For postnatal exposures, behavioral effects found in more than one study at 1 mg/kg-d were decreased errors on a radial arm maze in female rats and increased errors in males dosed subcutaneously from postnatal day (PND) 1 to 4. A similar finding was seen in rats exposed orally from PND 1 to 21 with incremental dose levels of 1, 2, and 4 mg/kg-d, but not in rats dosed with constant dose level of 1 mg/kg-d. Neurodevelopmental behavioral, pharmacological, and morphologic effects occurred at doses that produced significant brain or red blood cell acetylcholinesterase inhibition in dams or offspring.
TL;DR: Inclusion of lean beef in the diet increases the variety of available food choices, which may improve long-term adherence with dietary recommendations for lipid management and change in the fasting lipid profile were not significantly different with beef consumption compared with those with poultry and/or fish consumption.
TL;DR: Overall, the available evidence does not support a conclusion that a causal association has been established between occupational exposure to beryllium and the risk of cancer.
Abstract: There is controversy on whether occupational exposure to beryllium causes lung cancer. We conducted a systematic review of epidemiologic studies on cancer among workers exposed to beryllium, including a study of seven U.S. production plants which has been recently updated, a study of patients with beryllium disease (largely overlapping with the former study) and several smaller studies. A small excess mortality from lung cancer was detected in the large cohort, which was partially explained by confounding by tobacco smoking and urban residence. Other potential confounders have not been addressed. The excess mortality was mainly among workers employed (often for a short duration) in the early phase of the manufacturing industry. There was no relation with duration of employment or cumulative exposure, whereas average and maximum exposure were associated with lung cancer risk. The use of lagged exposure variables resulted in associations with lung cancer risk; however, these associations were due to confounding by year of birth and year of hire. The studies of beryllium disease patients do not provide independent evidence and the results from other studies do not support the hypothesis of an increased risk of lung cancer or any other cancer. Overall, the available evidence does not support a conclusion that a causal association has been established between occupational exposure to beryllium and the risk of cancer.
TL;DR: A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV(+) and EBV
TL;DR: In this article, it was shown that when a very intense positive cloud to ground lightning stroke leads to an elve and a high altitude sprite, and possibly a sprite halo as well, there is production of long lasting elevations in electron density at VLF reflection heights that cause LOREs and severe effects on VlF propagation.
Abstract: [1] Observations show that intense +CG lightning discharges which trigger both an elve and a sprite are associated with long-lasting conductivity modifications in the upperD-region ionosphere. They are observed as strong perturbations in VLF signals propagating through the disturbed region, manifested asLOng Recovery Early VLF events (LORE), which can last up to 30 minutes. These same ionospheric modifications are also responsible for step-like changes, seen mostly in off-storm VLF transmissions, which offset signal levels even for longer times. The evidence suggests that when a very intense positive cloud to ground lightning stroke leads to an elve and a high altitude sprite, and possibly a sprite halo as well, there is production of long lasting elevations in electron density at VLF reflection heights that cause LOREs and severe effects on VLF propagation. The present results confirm past predictions and postulations that elves may be accompanied by long-lasting electron density perturbations in the lower ionosphere.