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Extraordinary levels of per- and polyfluoroalkyl substances (PFAS) in vertebrate animals at a New Mexico desert oasis: Multiple pathways for wildlife and human exposure. ENVIRONMENTAL RESEARCH 2024; 249:118229. [PMID: 38325785 DOI: 10.1016/j.envres.2024.118229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/23/2023] [Accepted: 01/15/2024] [Indexed: 02/09/2024]
Abstract
Per- and polyfluoroalkyl substances (PFAS) in the environment pose persistent and complex threats to human and wildlife health. Around the world, PFAS point sources such as military bases expose thousands of populations of wildlife and game species, with potentially far-reaching implications for population and ecosystem health. But few studies shed light on the extent to which PFAS permeate food webs, particularly ecologically and taxonomically diverse communities of primary and secondary consumers. Here we conducted >2000 assays to measure tissue-concentrations of 17 PFAS in 23 species of mammals and migratory birds at Holloman Air Force Base (AFB), New Mexico, USA, where wastewater catchment lakes form biodiverse oases. PFAS concentrations were among the highest reported in animal tissues, and high levels have persisted for at least three decades. Twenty of 23 species sampled at Holloman AFB were heavily contaminated, representing middle trophic levels and wetland to desert microhabitats, implicating pathways for PFAS uptake: ingestion of surface water, sediments, and soil; foraging on aquatic invertebrates and plants; and preying upon birds or mammals. The hazardous long carbon-chain form, perfluorooctanosulfonic acid (PFOS), was most abundant, with liver concentrations averaging >10,000 ng/g wet weight (ww) in birds and mammals, respectively, and reaching as high 97,000 ng/g ww in a 1994 specimen. Perfluorohexanesulfonic acid (PFHxS) averaged thousands of ng/g ww in the livers of aquatic birds and littoral-zone house mice, but one order of magnitude lower in the livers of upland desert rodent species. Piscivores and upland desert songbirds were relatively uncontaminated. At control sites, PFAS levels were strikingly lower on average and different in composition. In sum, legacy PFAS at this desert oasis have permeated local aquatic and terrestrial food webs across decades, severely contaminating populations of resident and migrant animals, and exposing people via game meat consumption and outdoor recreation.
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Blood Variation Implicates Respiratory Limits on Elevational Ranges of Andean Birds. Am Nat 2023; 201:741-754. [PMID: 37130238 DOI: 10.1086/723222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
AbstractThe extent to which species ranges reflect intrinsic physiological tolerances is a major question in evolutionary ecology. To date, consensus has been hindered by the limited tractability of experimental approaches across most of the tree of life. Here, we apply a macrophysiological approach to understand how hematological traits related to oxygen transport shape elevational ranges in a tropical biodiversity hot spot. Along Andean elevational gradients, we measured traits that affect blood oxygen-carrying capacity-total and cellular hemoglobin concentration and hematocrit, the volume percentage of red blood cells-for 2,355 individuals of 136 bird species. We used these data to evaluate the influence of hematological traits on elevational ranges. First, we asked whether the sensitivity of hematological traits to changes in elevation is predictive of elevational range breadth. Second, we asked whether variance in hematological traits changed as a function of distance to the nearest elevational range limit. We found that birds showing greater hematological sensitivity had broader elevational ranges, consistent with the idea that a greater acclimatization capacity facilitates elevational range expansion. We further found reduced variation in hematological traits in birds sampled near their elevational range limits and at high absolute elevations, patterns consistent with intensified natural selection, reduced effective population size, or compensatory changes in other cardiorespiratory traits. Our findings suggest that constraints on hematological sensitivity and local genetic adaptation to oxygen availability promote the evolution of the narrow elevational ranges that underpin tropical montane biodiversity.
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The Effects of a Combination of Quillaja saponaria and Yucca schidigera on Eimeria spp. in Broiler Chickens. Avian Dis 2021; 64:300-304. [PMID: 33205178 DOI: 10.1637/aviandiseases-d-20-00016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/31/2020] [Indexed: 11/05/2022]
Abstract
A series of studies was carried out to determine the anticoccidial effects of a product derived from plant material sourced from Quillaja saponaria and Yucca schidigera. These plants are known to contain high concentrations of triterpenoid and steroidal saponins, substances that are known to display an array of biological effects. Battery tests involving individual Eimeria acervulina, Eimeria maxima, and Eimeria tenella infections and graded levels of a quillaja/yucca combination (QY) (0, 200, 250, and 300 ppm) were conducted. Body weight gain, coccidial lesion scores, and total oocysts per gram of feces (OPG) were used to evaluate anticoccidial effects. In addition, three floor pen trials evaluated the effects of 250 ppm QY in the control coccidial infections. The first pen trial measured the effects of 250 ppm QY, both alone and in combination with 66 ppm salinomycin (Sal), in a 2 3 2 factorial treatment arrangement. Two additional 42-day pen studies assessed the effects 250 ppm QY in birds vaccinated for coccidiosis. Data from the three battery trials indicated that at doses of 250 ppm QY or more, weight gain was improved, E. acervulina and E. tenella lesion scores were reduced, and OPG was lowered. In general, OPG was reduced by about 50% across all species by 250 and 300 ppm QY. Results of the pen study indicated that 250 ppm QY and Sal, when fed individually, reduced OPG and lesion scores and improved final performance. However, when QY and Sal were administered concurrently, further significant reductions in OPG occurred. The final performance of broilers vaccinated for coccidiosis was also improved at 250 ppm QY, as was OPG at both 21 and 28 days. Thus, at QY doses of 250 ppm or more, anticoccidial activity was evident but lacked the potency exhibited by many standard anticoccidials. When combined with either Sal or a live coccidiosis vaccine, QY improved the anticoccidial effects and performance of these anticoccidial methods.
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Detecting turnover among complex communities using null models: a case study with sky-island haemosporidian parasites. Oecologia 2021; 195:435-451. [PMID: 33484348 DOI: 10.1007/s00442-021-04854-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 01/08/2021] [Indexed: 11/26/2022]
Abstract
Turnover in species composition between sites, or beta diversity, is a critical component of species diversity that is typically influenced by geography, environment, and biotic interactions. Quantifying turnover is particularly challenging, however, in multi-host, multi-parasite assemblages where undersampling is unavoidable, resulting in inflated estimates of turnover and uncertainty about its spatial scale. We developed and implemented a framework using null models to test for community turnover in avian haemosporidian communities of three sky islands in the southwestern United States. We screened 776 birds for haemosporidian parasites from three genera (Parahaemoproteus, Plasmodium, and Leucocytozoon) by amplifying and sequencing a mitochondrial DNA barcode. We detected infections in 280 birds (36.1%), sequenced 357 infections, and found a total of 99 parasite haplotypes. When compared to communities simulated from a regional pool, we observed more unique, single-mountain haplotypes and fewer haplotypes shared among three mountain ranges than expected, indicating that haemosporidian communities differ to some degree among adjacent mountain ranges. These results were robust even after pruning datasets to include only identical sets of host species, and they were consistent for two of the three haemosporidian genera. The two more distant mountain ranges were more similar to each other than the one located centrally, suggesting that the differences we detected were due to stochastic colonization-extirpation dynamics. These results demonstrate that avian haemosporidian communities of temperate-zone forests differ on relatively fine spatial scales between adjacent sky islands. Null models are essential tools for testing the spatial scale of turnover in complex, undersampled, and poorly known systems.
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Demographic consequences of foraging ecology explain genetic diversification in Neotropical bird species. Ecol Lett 2021; 24:563-571. [PMID: 33389805 DOI: 10.1111/ele.13674] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/23/2020] [Accepted: 12/02/2020] [Indexed: 11/30/2022]
Abstract
Despite evidence that species' traits affect rates of bird diversification, biogeographic studies tend to prioritise earth history in Neotropical bird speciation. Here we compare mitochondrial genetic differentiation among 56 co-distributed Neotropical bird species with varying ecologies. The trait 'diet' best predicted divergence, with plant-dependent species (mostly frugivores and nectivores) showing lower levels of genetic divergence than insectivores or mixed-diet species. We propose that the greater vagility and demographic instability of birds whose diets rely on fruit, seeds, or nectar known to vary in abundance seasonally and between years relative to birds that eat primarily insects, drives episodic re-unification of otherwise isolated populations, resetting the divergence 'clock'. Testing this prediction using coalescent simulations, we find that plant-dependent species show stronger signals of recent demographic expansion compared to insectivores or mixed-diet species, consistent with this hypothesis. Our study provides evidence that localised ecological phenomena scale up to generate larger macroevolutionary patterns.
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Extreme and variable torpor among high-elevation Andean hummingbird species. Biol Lett 2020; 16:20200428. [PMID: 32898456 PMCID: PMC7532710 DOI: 10.1098/rsbl.2020.0428] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/14/2020] [Indexed: 11/12/2022] Open
Abstract
Torpor is thought to be particularly important for small endotherms occupying cold environments and with limited fat reserves to fuel metabolism, yet among birds deep torpor is both rare and variable in extent. We investigated torpor in hummingbirds at approximately 3800 m.a.s.l. in the tropical Andes by monitoring body temperature (Tb) in 26 individuals of six species held captive overnight and experiencing natural air temperature (Ta) patterns. All species used pronounced torpor, with one Metallura phoebe reaching a minimum Tb of 3.26°C, the lowest yet reported for any bird or non-hibernating mammal. The extent and duration of torpor varied among species, with overnight body mass (Mb) loss negatively correlated with both minimum Tb and bout duration. We found a significant phylogenetic signal for minimum Tb and overnight Mb loss, consistent with evolutionarily conserved thermoregulatory traits. Our findings suggest deep torpor is routine for high Andean hummingbirds, but evolved species differences affect its depth.
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The Long-Term Psychological Impact of Disclosing (Or Not) Laparoscopic Adjustable Gastric Banding Surgery. Bariatr Surg Pract Patient Care 2018. [DOI: 10.1089/bari.2017.0045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Wildlife warning reflectors and white canvas reduce deer-vehicle collisions and risky road-crossing behavior. WILDLIFE SOC B 2018. [DOI: 10.1002/wsb.862] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Diversity, abundance, and host relationships of avian malaria and related haemosporidians in New Mexico pine forests. PeerJ 2017; 5:e3700. [PMID: 28828279 PMCID: PMC5563434 DOI: 10.7717/peerj.3700] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/26/2017] [Indexed: 01/28/2023] Open
Abstract
Avian malaria and related haemosporidian parasites (genera Haemoproteus, Plasmodium, and Leucocytozoon) affect bird demography, species range limits, and community structure, yet they remain unsurveyed in most bird communities and populations. We conducted a community-level survey of these vector-transmitted parasites in New Mexico, USA, to describe their diversity, abundance, and host associations. We focused on the breeding-bird community in the transition zone between piñon-juniper woodland and ponderosa pine forests (elevational range: 2,150–2,460 m). We screened 186 birds representing 49 species using both standard PCR and microscopy techniques to detect infections of all three avian haemosporidian genera. We detected infections in 68 out of 186 birds (36.6%), the highest proportion of which were infected with Haemoproteus (20.9%), followed by Leucocytozoon (13.4%), then Plasmodium (8.0%). We sequenced mtDNA for 77 infections representing 43 haplotypes (25 Haemoproteus, 12 Leucocytozoon, 6 Plasmodium). When compared to all previously known haplotypes in the MalAvi and GenBank databases, 63% (27) of the haplotypes we recovered were novel. We found evidence for host specificity at the avian clade and species level, but this specificity was variable among parasite genera, in that Haemoproteus and Leucocytozoon were each restricted to three avian groups (out of six), while Plasmodium occurred in all groups except non-passerines. We found striking variation in infection rate among host species, with nearly universal infection among vireos and no infection among nuthatches. Using rarefaction and extrapolation, we estimated the total avian haemosporidian diversity to be 70 haplotypes (95% CI [43–98]); thus, we may have already sampled ∼60% of the diversity of avian haemosporidians in New Mexico pine forests. It is possible that future studies will find higher diversity in microhabitats or host species that are under-sampled or unsampled in the present study. Fortunately, this study is fully extendable via voucher specimens, frozen tissues, blood smears, parasite images, and documentation provided in open-access databases (MalAvi, GenBank, and ARCTOS).
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Under and over 50: exploring long-term weight-loss outcomes following laparoscopic adjustable gastric band by age and body mass index group. Surg Obes Relat Dis 2016; 12:1616-1621. [PMID: 27567036 DOI: 10.1016/j.soard.2016.05.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 04/04/2016] [Accepted: 05/31/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Laparoscopic adjustable gastric band (LAGB) surgery is used to enable individuals to lose weight. However, the long-term weight loss outcomes for individuals with a body mass index (BMI)≥50 kg/m2 and/or age≥50 years at time of banding remains debated. To date, data reported is largely from populations outside the United Kingdom. OBJECTIVES To explore long-term weight loss outcomes based on individuals' pre-LAGB age and BMI. SETTING Data were collected from individuals in the United Kingdom attending a national health service weight loss surgery service. METHOD Data pertaining to weight were collected in a prospective 5-year study in the United Kingdom. Individuals were grouped according to preoperative age and BMI before analysis. RESULTS Data from 53 individuals were analyzed. Individuals age≤49 years weighed 142.7±17.4 kg preoperatively, whereas individuals age≥50 years weighed 137.6±19.4 kg. Over the 5 years post-LAGB, significant weight loss was achieved by the whole sample. Additionally, there was an interaction between weight loss and age/BMI group. The sample had a significant percent total weight loss and percent excess weight loss between 6 months and 5 years post-LAGB. However, only individuals age≥50 years with a BMI≥50 kg/m2 preoperatively had continual weight loss over the 5 years. CONCLUSION Individuals lost weight following LAGB; however, only individuals with a BMI≥50 kg/m2 and age≥50 years before banding appeared to continue to lose weight as time since banding increased, compared with the other groups.
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The Importance of Dog Ownership: Implications for Long-Term Weight Reduction After Gastric Banding. Am J Lifestyle Med 2016; 11:86-89. [PMID: 30202318 DOI: 10.1177/1559827615606668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Gastric banding (GB) is considered an option to support weight loss for individuals who are unable to lose weight through diet and exercise alone. Exercise is an important element of maintaining gradual weight loss following GB. Dog walking may be one method to encourage exercise and contribute to continued weight loss. Over a 5-year period, 24 individuals aged between 31 and 58 years (21 female; 12 dog-owners) were weighed at 7 time points. Intention to treat MANOVA analysis showed both groups lost a significant amount of weight, F(6, 17) = 15.7, P = .001, ηp2 = .85, but no difference was observed between dog owners and non-dog owners, F(6, 17) = 0.66, P = .68, ηp2 = .19, although from 24 months postbanding, data indicated dog owners appear to weigh less than non-dog owners. Further longitudinal research is warranted beyond 5 year post-GB; and encouraging exercise through dog walking may be a useful adjunct to increasing activity and promoting weight loss following GB.
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Aspirin therapy is associated with less compact fibrin networks and enhanced fibrinolysis in patients with abdominal aortic aneurysm. J Thromb Haemost 2015; 13:795-801. [PMID: 25660763 DOI: 10.1111/jth.12872] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Thrombotic changes in fibrin networks contribute to increased cardiovascular risk in patients with abdominal aortic aneurysm (AAA). Given that aspirin modulates the fibrin network, we aimed to determine if aspirin therapy is associated with changes in ex-vivo fibrin clot characteristics in AAA patients and also conducted an exploratory analysis of 5-year mortality in these individuals. METHODS We recruited 145 male patients, divided into controls (aortic diameter < 3 cm, n = 49), AAA not taking aspirin (AAA-Asp, n = 50) and AAA on 75 mg day(-1) aspirin (AAA+Asp, n = 46), matched for aneurysm size. Characteristics of clots made from plasma and plasma-purified fibrinogen were investigated using turbidimetric analysis, permeation studies, and confocal and electron microscopy. Plasma fibrinogen, D-dimer and inflammatory marker levels were also measured. RESULTS Maximum absorbance (MA) of plasma clots from controls was lower than that of AAA patients not on aspirin (AAA-Asp) at 0.30 ± 0.01 and 0.38 ± 0.02 au, respectively (P = 0.002), whereas aspirin-treated subjects had MA similar to controls (0.31 ± 0.02 P = 0.9). Plasma clot lysis time displayed an identical pattern at 482 ± 15, 597 ± 24 and 517 ± 27 s for control, AAA-Asp and AAA+Asp (P = 0.001 and P = 0.8). The lysis time of clots made from purified fibrinogen of AAA-Asp was longer than that of AAA+Asp patients (756 ± 47 and 592 ± 52 s, respectively; P = 0.041). Permeation studies and confocal and electron microscopy showed increased clot density in AAA-Asp compared with the AAA+Asp group. Mortality in AAA-Asp and AAA+Asp was similar, despite increased cardiovascular risk in the latter group, and both exhibited higher mortality than controls. CONCLUSION Aspirin improves fibrin clot characteristics in patients with AAA, which may have important clinical implications.
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Comparison of measured and calculated dose rates near nuclear medicine patients. HEALTH PHYSICS 2013; 105:187-191. [PMID: 23799503 DOI: 10.1097/hp.0b013e318290cc0e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Widely used release criteria for patients receiving radiopharmaceuticals (NUREG-1556, Vol. 9, Rev.1, Appendix U) are known to be overly conservative. The authors measured external exposure rates near patients treated with I, Tc, and F and compared the measurements to calculated values using point and line source models. The external exposure dose rates for 231, 11, and 52 patients scanned or treated with I, Tc, and F, respectively, were measured at 0.3 m and 1.0 m shortly after radiopharmaceutical administration. Calculated values were always higher than measured values and suggested the application of "self-shielding factors," as suggested by Siegel et al. in 2002. The self-shielding factors of point and line source models for I at 1 m were 0.60 ± 0.16 and 0.73 ± 0.20, respectively. For Tc patients, the self-shielding factors for point and line source models were 0.44 ± 0.19 and 0.55 ± 0.23, and the values were 0.50 ± 0.09 and 0.60 ± 0.12, respectively, for F (all FDG) patients. Treating patients as unshielded point sources of radiation is clearly inappropriate. In reality, they are volume sources, but treatment of their exposures using a line source model with appropriate self-shielding factors produces a more realistic, but still conservative, approach for managing patient release.
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Abstract
Abstract
Background
Ongoing angiogenesis is implicated in the inflammatory environment that characterizes abdominal aortic aneurysm (AAA). Although lymphangiogenesis has been associated with chronic inflammatory conditions, it has yet to be demonstrated in AAA. The aim was to determine the presence of lymphangiogenesis and to delineate the relationship between inflammation and neovascularization in AAA tissue.
Methods
AAA samples and preoperative computed tomography images were obtained from patients undergoing elective AAA repair. Control samples were age-matched abdominal aortic tissue. Specific immunostains for blood vessels (CD31, CD105), lymphatic vessels (D2-40), vascular endothelial growth factor (VEGF) A and VEGF receptor (VEGFR) 3 allowed characterization and quantitation of vasculature.
Results
The AAA wall contained high levels of inflammatory infiltrate; microvascular densities of blood (P < 0·001) and lymphatic (P = 0·003) vessels were significantly increased in AAA samples compared with controls. Maximal AAA vascularity was observed in inflammatory areas, with vessels that stained positively for CD31 (ρ = 0·625, P = 0·017), CD105 (ρ = 0·692, P = 0·009) and D2-40 (ρ = 0·675, P = 0·008) correlating positively with the extent of inflammation. Increased VEGFR-3 and VEGF-A expression was also evident within inflammatory AAA areas.
Conclusion
These findings demonstrated lymphatic vessel involvement in end-stage AAA disease, which was associated with the degree of inflammation, and confirmed the involvement of neovascularization.
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Breast augmentation in Familial Partial Lipodystrophy: a case report. J Plast Reconstr Aesthet Surg 2011; 64:e121-4. [PMID: 21306965 DOI: 10.1016/j.bjps.2011.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 12/13/2010] [Accepted: 01/05/2011] [Indexed: 10/18/2022]
Abstract
Familial Partial Lipodystrophy (or Dunnigan-Kobberling syndrome) is characterised by the progressive loss of peripheral subcutaneous fat, with or without truncal involvement. The resultant physical changes in appearance may be dramatic, especially in women, and their psychological impact underestimated. There are limited reports regarding the role of reconstructive procedures to address the physical defects imposed by the various lipodystrophy syndromes, and much of the work to date has focused around facial lipoatrophy in patients with HIV-1 protease inhibitor induced disease. We, however, present a single case report pertaining to the role of breast augmentation in patients with truncal lipoatrophy, as in Familial Partial Lipodystrophy.
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Sea otter mortality in fish and shellfish traps: estimating potential impacts and exploring possible solutions. ENDANGER SPECIES RES 2011. [DOI: 10.3354/esr00327] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Satellite imagery reveals new critical habitat for Endangered bird species in the high Andes of Peru. ENDANGER SPECIES RES 2011. [DOI: 10.3354/esr00323] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Randomised controlled trial of the use of three dressing preparations in the management of chronic ulceration of the foot in diabetes. Health Technol Assess 2009; 13:1-86, iii-iv. [DOI: 10.3310/hta13540] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Wing-Tail Measurements of Bubo Virginianus from Texas. SOUTHWEST NAT 2008. [DOI: 10.1894/0038-4909(2008)53[128:wmobvf]2.0.co;2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Three studies were conducted with dairy cattle fed diets with added Co. The first study examined cow age and added dietary Co on Co in liver and blood. Nonpregnant, nonlactating Holstein cows were blocked by age (2.5 or 6.5 yr) and assigned to either a control diet or a diet supplemented with 9 mg Co per day. The Co concentration of liver, taken on d 60, was not affected by dietary Co but was higher in the younger cows. The cytosolic fraction of liver contained the most Co, and the subcellular distribution of Co was not affected by total Co in liver. In a second study, Holstein cows were assigned to one of three treatments of dietary Co from 21 d prepartum until 120 d postpartum. There was an interaction of time x treatment x parity such that milk yield response to Co supplementation differed between multiparous cows and primiparous cows. Supplemental Co did not increase Co in serum, colostrum, milk, or liver. Primiparous cows secreted colostrum and milk with higher Co concentrations than did multiparous cows. Likewise, serum B12 levels were higher in primiparous than multiparous cows and declined with increasing days in milk (DIM). Serum Co also decreased from 7 to 120 DIM. In a final study, a Co supplement in the starter diet did not affect Co in serum or liver of young calves. In conclusion, supplemental dietary Co did not affect secretion of Co in milk, tissue retention, or subcellular distribution of Co within the liver. Primiparous and multiparous cows differed in their milk yield response to dietary Co supplementation.
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Abstract
BACKGROUND AND OBJECTIVE Alexander disease is a slowly progressive CNS disorder that most commonly occurs in children. Until recently, the diagnosis could only be established by the histologic finding of Rosenthal fibers in brain specimens. Mutations in the glial fibrillary acidic protein (GFAP) gene have now been shown in a number of biopsy- or autopsy-proven patients with Alexander disease. A prospective study on patients suspected to have Alexander disease was conducted to determine the extent to which clinical and MRI criteria could accurately diagnose affected individuals, using GFAP gene sequencing as the confirmatory assay. METHODS Patients who showed MRI white matter abnormalities consistent with Alexander disease, unremarkable family history, normal karyotype, and normal metabolic screening were included in this study. Genomic DNA from patients was screened for mutations in the entire coding region, including the exon-intron boundaries, of the GFAP gene. RESULTS Twelve of 13 patients (approximately 90%) were found to have mutations in GFAP. Seven of those 12 patients presented in infancy with seizures and megalencephaly. Five were juvenile-onset patients with more variable symptoms. Two patients in the latter group were asymptomatic or minimally affected at the time of their initial MRI scan. The mutations were distributed throughout the gene, and all involved sporadic single amino acid heterozygous changes that changed the charge of the mutant protein. Four of the nine changes were novel mutations. CONCLUSIONS In symptomatic and asymptomatic patients with a predominantly frontal leukoencephalopathy by MRI, GFAP gene mutation analysis should be included in the initial diagnostic evaluation process for Alexander disease.
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Effects of supplementing combinations of inorganic and complexed copper on performance and liver mineral status of beef heifers consuming antagonists. J Anim Sci 2001; 79:2926-34. [PMID: 11768124 DOI: 10.2527/2001.79112926x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Performance, immune response, and liver trace mineral status were measured in growing heifers supplemented with different copper (Cu) concentrations and sources when diets contained the Cu antagonists Mo, S, and Fe. Sixty Angus x Hereford heifers were managed in two groups for 112 d and were either individually fed diets and mineral treatments using individual feeding stalls (Stall) or pen-fed grass hay and individually supplemented mineral treatments (Pen). The basal diet of grass hay, rolled barley, and soybean meal was analyzed to contain 6 mg Cu/kg DM. The treatments consisted of 1) no supplemental Cu (Control); 2) 49 mg Cu/kg DM from Cu sulfate (i.e. approximately five times NRC recommendation for Cu from CuSO4) (5X-SO4); 3). 22 mg Cu/kg DM from CuSO4 (2X-SO4); 4). 22 mg Cu/kg DM from a combination of 50% CuSO4 and 50% Cu-amino acid complex (50-50); and 5). 22 mg Cu/kg DM from a combination of 25% CuSO4, 50% Cu-amino acid complex, and 25% Cu oxide (CuG) (25-50-25). All heifers were supplemented with the Cu antagonists Mo (10 mg/kg DM), S (2,900 mg/kg DM), and Fe (500 mg/kg DM). These diets resulted in dietary Cu:Mo ratios that averaged 0.5:1 for Control, 4.5:1 for the 5X-SO4, and 2.4:1 for 2X-SO4, 50-50, and 25-50-25. Rate and efficiencies of gain and cell-mediated immune function were not different (P > 0.10) among treatments. Data suggest supplements containing combinations of inorganic and complexed Cu interacted differently in the presence of Mo, S, and Fe. Heifers consuming the 25-50-25 supplement in the Stall group initially lost hepatic Cu rapidly but this loss slowed from d 50 to d 100 compared to the Control (P = 0.07), 50-50 (P < 0.05), and 2X-SO4 (P < 0.05) heifers and was similar (P > 0.10) to that in the 5X-SO4 heifers. In the Pen group, total hepatic Cu loss tended to be greater for 25-50-25 and 2X-SO4 compared to 5X-SO4 heifers (P = 0.09 and P = 0.06, respectively); Cu loss in the 50-50 heifers was similar (P > 0.10) to that in the 5X-SO4 heifers. This suggests that supplementing combinations of inorganic and amino acid-complexed Cu was as effective in limiting hepatic Cu loss during antagonism as was increasing dietary Cu levels to five times the NRC recommendation. A combination of 25% CuSO4 , 50% Cu-amino acid complex, and 25% CuO limited liver accumulation of Mo compared to supplements without CuO and could provide a strategic supplementation tool in limiting the systemic effects of Cu antagonism in beef cattle.
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Update on white matter genetic disorders. Pediatr Neurol 2001; 25:347-8; author reply 348. [PMID: 11704412 DOI: 10.1016/s0887-8994(01)00340-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Effects of inorganic and organic copper supplemented to first-calf cows on cow reproduction and calf health and performance. J Anim Sci 2001; 79:1650-9. [PMID: 11465350 DOI: 10.2527/2001.7971650x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Two experiments were conducted to determine whether the supplementation of Cu in the organic or inorganic form to 2-yr-old cows, before and after calving, affects reproduction rate, calf health and performance, passive transfer of immunoglobulin, or liver and serum Cu concentrations compared with unsupplemented controls. Cows (n = 75 in 1997; n = 120 in 1998) were randomly assigned by estimated calving date and body condition score to one of three treatments: 1) Control, control; 2) Inorganic, inorganic Cu supplement (200 mg Cu from CuSO4); 3) Organic, organic Cu supplement (100 mg Cu from AvailaCu). In 1998, a fourth treatment was added; 4) CU-ZN, organic Cu and Zn (400 mg Zn from AvailaZn in the Organic diet). Cows were fed a hay-based diet and individually fed supplements for approximately 45 d before and 60 d after calving (approximately January 15 to May 15 each year). Liver biopsies were obtained from cows before supplementation began, and from cows and calves at 10 and 30 d after calving. Blood samples were obtained from both cows and calves at calving, and colostrum samples were collected for IgG and mineral content. Cow liver Cu concentrations before supplementation began were 58 mg/kg in 1997 and 40 mg/kg (DM basis) in 1998. By 10 d after calving, liver Cu concentrations of Control cows had decreased (P < 0.05) to 24 mg/kg (Cu deficient) in both years, whereas liver Cu concentrations of Cu-supplemented cows increased (P < 0.05) in both years. Calf liver Cu concentrations at 10 d of age were similar (P > 0.10) for all treatment groups. No differences (P > 0.10) were found in colostrum Cu concentrations, or in calf health among treatments. No differences (P > 0.10) were found in cow BW change, calf serum Cu concentrations, calf weaning weights, or in cow 60-d pregnancy rates among treatments in either year. In 1998, cows in the Organic group had higher (P < 0.05) 30-d pregnancy rate than Control cows. Neither serum samples nor placental tissue were reliable indicators of Cu status in cows. Feeding supplemental Cu (either inorganic, organic, or organic with extra Zn) to cows with liver Cu concentrations of approximately 50 mg/kg before calving did not improve cow 60-d pregnancy rates or the health and performance of their calves when compared with unsupplemented cows.
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Abstract
Prior to finding that GFAP mutations underlie many cases of Alexander disease, it was unclear whether the disease originated in astrocytes or if the formation of Rosenthal fibers was a response to an external insult. It was also unclear whether the etiology of the disease was environmental or genetic. For many cases of Alexander disease, these questions have now been answered. An immediate clinical benefit of this discovery is the possibility of diagnosing most cases of Alexander disease through analysis of patient DNA samples, rather than resorting to brain biopsy. In addition, fetal testing is now an option for parents who have had an Alexander disease child with an identified mutation and who wish to have additional children. For the future, these mutations should provide a unique window for illuminating the mechanism of the disease.
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Mitochondrial abnormalities in Alzheimer's disease. J Neurosci 2001; 21:3017-23. [PMID: 11312286 PMCID: PMC6762571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The finding that oxidative damage, including that to nucleic acids, in Alzheimer's disease is primarily limited to the cytoplasm of susceptible neuronal populations suggests that mitochondrial abnormalities might be part of the spectrum of chronic oxidative stress of Alzheimer's disease. In this study, we used in situ hybridization to mitochondrial DNA (mtDNA), immunocytochemistry of cytochrome oxidase, and morphometry of electron micrographs of biopsy specimens to determine whether there are mitochondrial abnormalities in Alzheimer's disease and their relationship to oxidative damage marked by 8-hydroxyguanosine and nitrotyrosine. We found that the same neurons showing increased oxidative damage in Alzheimer's disease have a striking and significant increase in mtDNA and cytochrome oxidase. Surprisingly, much of the mtDNA and cytochrome oxidase is found in the neuronal cytoplasm and in the case of mtDNA, the vacuoles associated with lipofuscin. Morphometric analysis showed that mitochondria are significantly reduced in Alzheimer's disease. The relationship shown here between the site and extent of mitochondrial abnormalities and oxidative damage suggests an intimate and early association between these features in Alzheimer's disease.
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Mutations in GFAP, encoding glial fibrillary acidic protein, are associated with Alexander disease. Nat Genet 2001; 27:117-20. [PMID: 11138011 DOI: 10.1038/83679] [Citation(s) in RCA: 453] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alexander disease is a rare disorder of the central nervous system of unknown etiology. Infants with Alexander disease develop a leukoencephalopathy with macrocephaly, seizures and psychomotor retardation, leading to death usually within the first decade; patients with juvenile or adult forms typically experience ataxia, bulbar signs and spasticity, and a more slowly progressive course. The pathological hallmark of all forms of Alexander disease is the presence of Rosenthal fibers, cytoplasmic inclusions in astrocytes that contain the intermediate filament protein GFAP in association with small heat-shock proteins. We previously found that overexpression of human GFAP in astrocytes of transgenic mice is fatal and accompanied by the presence of inclusion bodies indistinguishable from human Rosenthal fibers. These results suggested that a primary alteration in GFAP may be responsible for Alexander disease. Sequence analysis of DNA samples from patients representing different Alexander disease phenotypes revealed that most cases are associated with non-conservative mutations in the coding region of GFAP. Alexander disease therefore represents the first example of a primary genetic disorder of astrocytes, one of the major cell types in the vertebrate CNS.
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Foamy cells with oligodendroglial phenotype in childhood ataxia with diffuse central nervous system hypomyelination syndrome. Acta Neuropathol 2000; 100:635-46. [PMID: 11078215 DOI: 10.1007/s004010000234] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Childhood ataxia with diffuse central nervous system hypomyelination syndrome (CACH) is a recently described leukodystrophy of unknown etiology. To characterize the neuropathological features and gain insight as to the pathogenesis of this disorder, we studied cerebral tissue from six patients with the CACH syndrome. Evaluation of toluidine blue-stained, semithin sections of white matter from CACH patients disclosed unusual cells with "foamy" cytoplasm, small round nuclei and fine chromatin. Electron microscopy (EM) revealed cells in the white matter with abundant cytoplasm containing many mitochondria and loosely clustered, membranous structures, but lacking the lysosomal structures seen in macrophages. Further analysis of tissue sections with antibodies and special stains demonstrated that the abnormal cells with abundant cytoplasm labeled with oligodendroglial markers, but did not react with macrophage or astrocytic markers. Double immunolabeling with macrophage and oligodendroglial markers clearly distinguished macrophages from the "foamy" oligodendroglial cells (FODCs). Proteolipid protein (PLP) mRNA in situ hybridization demonstrated PLP mRNA transcripts in a high proportion of oligodendrocytes in CACH patients compared to control patients, and PLP mRNA transcript signal in cells, morphologically consistent with FODCs. Normal and pathological brain control tissues did not contain FODCs. These neuropathological findings will be useful pathological identifiers of CACH, and may provide clues to the pathogenesis of this disorder.
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Impact of redox conditions on metolachlor and metribuzin degradation in Mississippi flood plain soils. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2000; 35:689-704. [PMID: 11069013 DOI: 10.1080/03601230009373302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of soil redox conditions on the degradation of metolachlor and metribuzin in two Mississippi soils (Forrestdale silty clay loam and Loring silt loam) were examined in the laboratory. Herbicides were added to soil in microcosms and incubated either under oxidized (aerobic) or reduced (anaerobic) conditions. Metolachlor and metribuzin degradation under aerobic condition in the Forrestdale soil proceeded at rates of 8.83 ngd(-1) and 25 ngd(-1), respectively. Anaerobic degradation rates for the two herbicides in the Forestdale soil were 8.44 ngd(-1) and 32.5 ngd(-1), respectively. Degradation rates for the Loring soil under aerobic condition were 24.8 ngd(-1) and 12.0 ngd(-1) for metolachlor and metribuzin, respectively. Metolachlor and metribuzin degradation rates under anaerobic conditions in the Loring soil were 20.9 ngd(-1) and 5.35 ngd(-1). Metribuzin degraded faster (12.0 ngd(-1)) in the Loring soil under aerobic conditions as compared to anaerobic conditions (5.35 ngd(-1)).
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Abstract
BACKGROUND Laparoscopic cancer surgery is limited by concerns about port-site metastasis. No study has definitively addressed the behavior and growth of tumor cells after the use of specific laparoscopic gases. METHODS In athymic rats, 10,000 colon cancer cells were injected intraperitoneally. The rats received either no pneumoperitoneum (pneumo) or pneumo (8 mmHg, 10 min) with carbon dioxide (CO(2)), nitrous oxide (N(2)O), or air. Two full-thickness incisions were made and closed in the upper abdomen of each animal. After 4 weeks, implants were identified grossly at necropsy, and invasiveness was scored according to penetration through the layers of the abdominal wall. RESULTS Rats receiving pneumo had more frequent implants (p < 0.01) with deeper penetration (p < 0.001) than rats not receiving pneumo. Implants were more common after air pneumo than after CO(2) (p < 0.05) or N(2)O (p = 0.07) pneumo, and were less penetrating after CO(2) pneumo than after air (p < 0.001) or N(2)O (p < 0.05) pneumo. CONCLUSIONS Carbon dioxide gas may limit the viability and invasiveness of free intraperitoneal tumor cells, as compared with air or N(2)O.
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Abstract
Five commercial dairy herds in Central New York fed metal-specific amino acid complexes were selected to evaluate digital characteristics. During the first year (period 1), herds were evaluated by a specific procedure by one individual. Three herds were not supplemented and two herds were supplemented with zinc methionine. During the subsequent year (period 2) all herds were switched to a combination of zinc methionine, copper lysine, manganese methionine, and cobalt glucoheptonate and evaluated in the same way as during period 1. There was no effect of period on incidence of heel erosion and interdigital dermatitis. During period 2, there was a reduced incidence of double soling, white line separation, sole hemorrhages, sole ulcers, and papillomatous digital dermatitis, and the incidence of wall ridges tended to be reduced compared with period 1. There was no effect of period on the incidence of abaxial wall lesions, digital arthritis, or foot rot, although the overall incidence of these disorders was low. During period 2, when cows were fed a combination of complexed trace minerals, there was a general reduction in the incidence of digital disorders associated with the laminitis syndrome complex compared with period 1; however, other time-related differences existed that may confound interpretation.
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Abstract
OBJECTIVES To determine the dependence of plasma leptin concentrations upon circulating noradrenaline (NA) and thyroid hormones (TH) in humans. DESIGN Cross-sectional study in 40 newly diagnosed untreated patients with primary thyroid disease, and 69 lean and obese euthyroid control subjects. MEASUREMENTS Plasma leptin, NA, free T3 (fT3) and TSH in the fasting state. Anthropometry and % body fat (electrical bioimpedance). RESULTS Leptin levels were highest in 37 obese euthyroid and 22 hypothyroid (median [interquartiles]31.5 [19.0- 48.0], 19.2 [11.5-31.5] ng ml(-1)), and lowest in 32 lean euthyroid and 18 hyperthyroid subjects (6.6 [3.9-14.4], 8.9 [5.5-11.1]; ANOVA, P< 0.0001). Plasma NA was similar in all groups (P= n.s.). In obese controls, TSH correlated with % body fat and leptin (r= 0.67, r= 0.61; P< 0.001). Treatment of hypothyroidism (n= 10) with T4 reduced leptin from 20.8 [11.8-31.6] to 12.9[4.6-21.2] (P= 0.005) with no change in BMI. CONCLUSIONS Thyroid status modifies leptin secretion independently of adiposity and NA. The data suggest leptin-thyroid interactions at hypothalamic and adipocyte level.
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Abstract
The effects of feeding different sources and quantities of Cu to heifers were evaluated in a 211-d experiment. Forty crossbred predominantly Brahman x Hereford heifers averaging 13.5 mo of age and 301 kg were initially depleted of Cu. The depletion diet was fed for 70 d and consisted of low Cu and high antagonist minerals, Fe, S, and Mo at 1000 mg/kg, 0.5%, and 5 mg/kg (dry basis), respectively. On d 71, heifers continued to receive the antagonistic minerals and were allotted equally to five Cu treatments: 1) control, no additional Cu source; 2) 8 mg of Cu/kg from CuSO4; 3) 16 mg of Cu/kg from CuSO4; 4) 8 mg of Cu/kg from Cu lysine; and 5) 16 mg of Cu/kg from Cu lysine. When no notable change in concentration of Cu in the liver was observed, d 169, a second diet was formulated. The heifers were fed the same Cu treatments, but S and Mo were removed and Fe was lowered to 50 mg/kg. This diet was then fed for the final 42 d of the experiment. In addition to performance, concentrations of Cu, Fe, and Zn in the plasma and liver, plasma ceruloplasmin, hemoglobin, superoxide dismutase (SOD) activity of neutrophils and lymphocytes, and a cell mediated immune response (phytohemagglutinin-P, PHA) were measured. Heifers in this study had increased growth over time, but there were no treatment differences for growth and average daily gain. Liver and plasma Cu concentrations were not greatly influenced by different supplemental Cu sources. However, compared with other treatments, Cu lysine (16 mg/kg) increased liver Cu in cattle that were deficient and tended to increase plasma Cu in animals that were marginally deficient in Cu. Iron concentrations decreased over time in liver and plasma, but there was no difference in Fe and Zn concentrations in liver and plasma among treatments. Differences in ceruloplasmin and hemoglobin concentrations were significant over time but not among treatments. The SOD activity in neutrophils did not change over time, but SOD activity of lymphocytes increased over time. For the PHA immune response test, there was no effect of time or a time by treatment interaction. These data suggest that all Cu sources were available, but Cu at 16 mg/kg from Cu lysine was more beneficial than were other sources and particularly for heifers with low Cu status.
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AMPA receptor protein expression and function in astrocytes cultured from hippocampus. J Neurosci Res 1999; 57:557-71. [PMID: 10440906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Glutamate receptors guide the proliferation, migration, and differentiation of glial cells. Here, we characterize AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid) and NMDA receptor protein expression and function and mRNA expression in hippocampal glial cultures. By immunocytochemistry, GluR2 (the subunit that limits the Ca(2+) permeability of AMPA receptors) exhibited prominent labeling in hippocampal glial cultures. Double-labeling of GluR2 with GFAP and with A2B5 revealed GluR2 subunit expression on type-1 and type-2 astrocyte lineage cells. GluR1 subunit expression was more prominent in type-1 than in type-2 astrocytes. To characterize functional properties of glutamate receptors expressed in cultured hippocampal astrocytes, we performed whole-cell patch clamp recording. Application of L-glutamate, AMPA, and kainate, but not NMDA, to small, rounded cells (morphologically identified as type-2 astrocytes) elicited inward currents which were blocked by the AMPA/kainate antagonist 6-cyano-7-nitroquinoxaline-2, 3-dione (CNQX). Cyclothiazide potentiated AMPA- and kainate-elicited currents, indicative of AMPA-preferring receptors. Current voltage analysis indicated that type-2 astrocyte AMPA receptors were electrically linear, indicative of GluR2-containing, Ca(2+)-impermeable AMPA receptors. By Northern blot analysis, GluR1 mRNA was highest in astrocyte cultures from cerebellum and hippocampus and moderate in astrocyte cultures from neocortex and striatum. GluR3 mRNA was detectable in astrocyte cultures from cerebellum and neocortex. GluR2 and NR1 mRNA expression were not detected in astrocytes cultured from any brain region examined. In situ hybridization studies showed wide expression of GluR1 mRNA in cultured astrocytes; GluR2 and GluR3 mRNAs were near background levels. Thus, cultured type-2 astrocytes express functional AMPA receptors in a cell-specific and region-specific manner, consistent with their role in neuronal-glial communication.
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Abstract
BACKGROUND Columnar-lined esophagus with intestinal metaplasia (IM), also called Barrett's esophagus, is a manifestation of severe gastroesophageal reflux (GER) and may predict poor symptom relief and high failure rate after fundoplication. We compared symptom scores and reoperation rates in GER patients with and without Barrett's esophagus. METHODS Between July 1992 and July 1997, 646 patients underwent fundoplication (626 laparoscopic). Of 150 endoscopic biopsies of suspected columnar-lined esophagus, 80 confirmed IM, 50 identified cardiac or fundic epithelium, and 20 revealed only esophagitis. Typical GER symptoms were scored by patients preoperatively and postoperatively (0 to 4 scale). We compared symptom response (Wilcoxon rank sum test) and failure rates (t test) in patients with IM and GER controls without IM. Preoperative data were available for 74 IM patients and 496 controls. One-year follow-up was available in 45 IM patients and 301 controls. Intermediate follow-up (2 to 5 years) was available in 20 IM patients and 99 controls. RESULTS Preoperatively and postoperatively, patients with IM reported heartburn, regurgitation, and dysphagia scores similar to controls. Procedure failure, requiring redo fundoplication, appeared more likely in IM patients than controls (6.3% versus 2.5%), but this difference did not reach statistical significance (P = 0.061). CONCLUSION Fundoplication provides equivalent symptom relief for patients with and without IM.
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Effects of supplementation of organic and inorganic combinations of copper, cobalt, manganese, and zinc above nutrient requirement levels on postpartum two-year-old cows. J Anim Sci 1999; 77:522-32. [PMID: 10229347 DOI: 10.2527/1999.773522x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The objective of this study was to determine whether a combination of Cu, Co, Mn, and Zn in an organic or inorganic form fed at higher than nutrient recommendations for 2-yr-old cows from calving to breeding would affect pregnancy rate, calving date, calf performance, and cow liver and serum mineral concentrations. Crossbred 2-yr-old cows were used after calving in 1994 (n = 127) and 1995 (n = 109). Cows were blocked by calving date to one of three treatments: 1) no supplemental minerals (CTL), 2) organic minerals (ORG), or 3) inorganic minerals (ING). Minerals were fed for the same daily intake for both organic and inorganic treatments: Cu (125 mg), Co (25 mg), Mn (200 mg), and Zn (360 mg). Cows were individually fed a mineral-protein supplement with grass hay from calving (February-March) to before breeding (May 15). Hay intakes were calculated using chromium oxide boluses to determine fecal output. Fecal excretion of minerals was calculated following trace element analysis of feces. Liver biopsies were obtained before calving, after calving (start of supplementation), at the end of supplementation, and in midsummer. Over 2 yr, more cows did not become pregnant (P < .01) in ORG (11/78) and ING (11/78) treatments than in CTL (0/80) treatments. A treatment x year interaction was found for day of conception. Cows in the ORG group conceived later (P < .01) than cows in the ING or CTL groups in 1994. In 1995, there was no difference (P > .10) in day of conception among groups. Liver Zn and Mn concentrations were not different (P > .10) and Cu concentrations increased (P < .01) for the ORG and ING groups. Cows in the ORG and ING groups had higher (P < .01) concentrations of Cu, Mn, and Zn in the feces than the CTL cows. Trace elements in the feces did not differ for ORG and ING groups. Results indicate that combinations of Cu, Co, Mn, and Zn fed at higher levels than are required reduced reproductive performance.
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Abstract
BACKGROUND Antireflux operations restore lower esophageal sphincter (LES) function and hiatal anatomy; however, the relative contributions are unclear. METHODS We measured the competency of fundoplications, exclusive of in vivo variables, in gastroesophageal explants from 8 cadavers. Using a multichannel manometer, esophageal, LES, and intragastric pressures were recorded during transpyloric distension. Data were compared at baseline, and after Nissen (360 degrees) and Toupet (270 degrees) fundoplications. RESULTS Before fundoplication, stomachs refluxed immediately upon distension. Nissen fundoplications never refluxed before gastric rupture (46.8 +/- 15.0 mm Hg). LES pressure averaged 2.0 +/- 0.5 times intragastric pressure during distension. Toupet fundoplications refluxed at intragastric pressure <2 mm Hg, then became competent until gastric rupture (49.9 +/- 15.0 mm Hg). LES pressure averaged 2.4 +/- 1.0 times intragastric pressure during distension. CONCLUSIONS Nissen and Toupet fundoplications increase LES pressure linearly at 2 to 2.5 times intragastric pressure, independent of in vivo variables. Toupet fundoplication lacks the competency of Nissen fundoplication at low intragastric pressures.
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Current activities at the Centers for Disease Control and Prevention's National Diabetes Laboratory. Diabetes Technol Ther 1999; 1:403-9. [PMID: 11474824 DOI: 10.1089/152091599316919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In 1997, the Centers for Disease Control and Prevention established the National Diabetes Laboratory in order to help prevent and treat type 1 diabetes. This state-of-the-art laboratory collaborates with research scientists and key national and international organizations throughout the world to identify and study risk factors for type 1 diabetes by developing measurements for glycosylated proteins, developing and evaluating technology for measuring genetic risk factors for the disease, and working to standardize autoantibody measurements. Developing improved technologies for diagnosing and managing diabetes and developing reference materials for properly calibrating and standardizing blood glucose meters are also critical aspects of the laboratory's work. In addition, the laboratory provides quality storage for valuable collections of biologics and other materials and facilitates sharing of specimens, associated epidemiologic data, and test results. Working with our partners in diabetes research, we are improving the diagnosis, treatment, and prevention of type 1 diabetes.
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Abstract
OBJECTIVE To study interactions between leptin and the pituitary-thyroid axis, both in euthyroid and dysthyroid states. SUBJECTS AND MEASUREMENTS We investigated the relationships of plasma leptin to levels of free thyroid hormones and TSH in 18 patients with newly diagnosed hyperthyroidism, 22 with newly diagnosed primary hypothyroidism, and 32 lean (body mass index [BMI] < 30) and 37 obese (BMI > 30 kg/m2) euthyroid subjects. Hypothyroid patients were restudied during thyroxine replacement treatment. RESULTS Median [interquartile range] plasma leptin concentrations were highest in obese euthyroid subjects (31.5 [19.0-48.0] and in untreated hypothyroid patients (19.2 [11.5-31.5]), and lowest levels in untreated hyperthyroid patients (8.9 [5.5-11.1]) and lean euthyroid control subjects (6.6 [3.9-14.4] micrograms/l (Kruskall-Wallis one-way analysis of variance; P < 0.0001). In euthyroid subjects, plasma leptin levels were higher in obese than in lean subjects (P < 0.00001). In obese subjects plasma levels of TSH correlated with percentage body fat (r = 0.67; P < 0.001) and plasma leptin (r = 0.61; P < 0.001). In untreated hyperthyroid subjects plasma leptin was unrelated to free T3, and in untreated hypothyroidism plasma leptin was unrelated to either free T3 or TSH concentrations (all P = NS). In untreated hyperthyroid, but not hypothyroid, patients plasma leptin concentrations correlated with BMI (r = 0.57; P = 0.02). Treatment of hypothyroidism with thyroxine resulted in a significant reduction in plasma leptin concentrations from 20.8 (11.8 to 31.6) to 12.9 (4.6-21.2) micrograms/l (P = 0.005), but BMI did not change significantly in the hypothyroid subjects being studied prospectively. CONCLUSIONS (i) In euthyroid subjects, plasma leptin and TSH levels correlate, and both are positively correlated with adiposity. (ii) Plasma leptin was significantly elevated in hypothyroid subjects, to levels similar to those seen in obese euthyroid subjects. (iii) Treatment of hypothyroidism resulted in a reduction in the raised plasma leptin levels. The data are consistent with the hypothesis that leptin and the pituitary-thyroid axis interact in the euthyroid state, and that hypothyroidism reversibly increases leptin concentrations.
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Laparoscopic Collis gastroplasty and Nissen fundoplication. A new technique for the management of esophageal foreshortening. Surg Endosc 1998; 12:1055-60. [PMID: 9685542 DOI: 10.1007/s004649900780] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND The short esophagus increases the difficulty and limits the effectiveness of laparoscopic Nissen fundoplication. In out experience, approximately 20-25% of esophagi judged by preoperative criteria to be foreshortened will, after dissection, be insufficiently long to allow 2 cm of esophagus to reside below the diaphragm without inferior distraction (i.e., tension free). Collis gastroplasty combined with Nissen fundoplication has become the standard approach for the creation of an intraabdominal neoesophagus and fundic wrap. METHODS After developing methods of performing totally laparoscopic stapled gastroplasty in the cadaver lab in 1994, we started applying the technique clinically in 1966. We performed 220 laparoscopic antireflux procedures between January 1966 and July 1997. Of these 220 patients, 26% were suspected to have esophageal foreshortening based on preoperative barium studies and/or endoscopy. RESULTS After hiatal dissection, nine patients, or 16% of those suspected to have esophageal foreshortening and 4% of the entire population, required the laparoscopic Collis-Nissen procedure. There was symptomatic improvement in all patients as assessed by patient-initiated symptom scores. CONCLUSIONS The management of patients with esophageal foreshortening is a complex problem. We believe that our technique of laparoscopic Collis-Nissen provides an effective means of achieving intraabdominal placement of the fundic wrap while maintaining the benefits of minimally invasive approach.
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Laparoscopic appendectomy is an acceptable alternative for the treatment of perforated appendicitis. Surg Endosc 1998; 12:940-3. [PMID: 9632866 DOI: 10.1007/s004649900752] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Ever since laparoscopy was first applied to the treatment of appendicitis, a controversy has existed as to whether the acknowledged benefits of a minimally invasive approach warrant its preference over the conventional treatment, which historically has had relatively low morbidity. The purpose of this study was to determine if laparoscopic appendectomy should be performed preferentially in cases where surgeons are not limited by technical constraints. METHODS A retrospective chart review was performed of 112 patients operated on for suspected appendicitis from June 1995 to July 1996. Forty-eight patients underwent laparoscopic appendectomy, and 64 had conventional open appendectomy. Laparoscopic appendectomy was performed using a three-trocar technique and the endoscopic stapler. RESULTS The histopathological diagnosis of appendicitis was confirmed in 82.6% of cases. Overall, laparoscopic appendectomy reduced length of hospital stay (1.54 versus 4.09 days; p < 0.0001) compared to conventional open appendectomy, with no significant difference in hospital cost ($6430 versus $6669; p = ns). Although the total OR time was longer in the laparoscopic group (75.8 versus 60.2 min; p < 0.0001), laparoscopy resulted in both a reduction in length of stay (2.17 versus 6.27 days; p < 0.0001) and hospital cost ($7506 versus $10,504; p < 0.02) for cases of perforated appendicitis. Conversion to open appendectomy was performed in 6% of patients, all of whom had perforated appendicitis. CONCLUSIONS Our data suggest that most cases of acute appendicitis with suspected perforation could be managed laparoscopically. Laparoscopic appendectomy significantly reduces length of stay and hospital costs in patients with perforated appendicitis.
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Alternative methods for management of the complicated gallbladder. SEMINARS IN LAPAROSCOPIC SURGERY 1998; 5:115-20. [PMID: 9594038 DOI: 10.1177/155335069800500206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Laparoscopic cholecystectomy is the procedure of choice for symptomatic cholelithiasis. However, in the presence of acute cholecystitis, 10% to 15% of patients face conversion to laparotomy. Alternatives to conventional therapy may therefore help to improve the clinical outcome of patients with complicated gallbladder disease. In selecting patients for alternative therapies, preoperative and intraoperative factors must be considered. Preoperative factors include the severity of biliary disease and preexisting medical risk factors; whereas intraoperative factors include conditions at the time of surgery that make dissection difficult or unsafe. Alternative therapies provide the least invasive management to safely temporize or definitively treat the acute condition. These alternatives include percutaneous cholecystostomy alone or followed by laparoscopic cholecystectomy, laparoscopic cholecystostomy followed by laparoscopic cholecystectomy, laparoscopic subtotal cholecystectomy, endoscopic retrograde cannulation of the gallbladder, and extracorporeal shockwave lithotripsy. By appropriate selection of the initial therapeutic approach, the surgeon may ultimately improve the clinical outcome in these complicated patients.
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A comparison of automated fructosamine and HbA1c methods for monitoring diabetes in pregnancy. Ann Clin Biochem 1998; 35 ( Pt 2):283-9. [PMID: 9547902 DOI: 10.1177/000456329803500214] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Two automated methods for measuring fructosamine (Test Plus and the original fructosamine assay) and glycated haemoglobin (Tina-quant immunoassay) were compared to determine which is the best index of blood glucose control during pregnancy. Thirteen women with type 1 diabetes were studied, with four-weekly measurements of HbA1c and fructosamine Test Plus using a Hitachi 911 analyser and fructosamine measured using an Olympus AU800 analyser. HbA1c correlated better (r = 0.573) with mean blood glucose (MBG) concentration than did fructosamine Test Plus (r = 0.347), even after correction for total protein concentration (r = 0.463), while there was no significant correlation with the original fructosamine method (r = 0.201). HbA1c correlated better with fasting/pre-prandial MBG concentrations, whereas fructosamine Test Plus correlated better with post-prandial MBG concentrations. Fructosamine Test Plus decreased with gestational age, and correlated with albumin and total protein concentrations, whereas HbA1c did not change with gestational age. Thus, HbA1c and fructosamine Test Plus were found to be useful in verifying home blood glucose measurements in diabetic pregnancy, with HbA1c being the best predictor of MBG concentration.
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Zinc repletion with organic or inorganic forms of zinc and protein turnover in marginally zinc-deficient calves. J Anim Sci 1997; 75:3074-81. [PMID: 9374325 DOI: 10.2527/1997.75113074x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We conducted two experiments using marginally Zn-deficient (-Zn) calves to determine which supplemental chemical form of Zn would most rapidly reverse certain Zn deficiency signs and to determine whether a change in protein turnover had occurred in Zn deficiency. In Exp. 1, 40 crossbred beef heifers were allocated by BW to four groups. The control group received 23 mg Zn/kg diet DM from ZnSO4 supplemented to the -Zn diet (17 mg Zn/kg diet DM). The three other groups received the -Zn diet. After 21 d, based on a decreased (P < .05) feed efficiency, they were deemed -Zn. Cell-mediated immune (CMI) response to phytohemagglutinin (PHA) was reduced (P < .05) but plasma and liver Zn were unaffected in the -Zn calves. Zinc was repleted by feeding iso-Zn amounts (23 mg Zn/kg diet DM) from Zn lysine, Zn methionine, or ZnSO4. At 8 h after injection of PHA, control CMI response values were similar to Zn Methionine, and Zn lysine was lower (P < .05). In Exp. 2, 10 Holstein steers were allocated by BW to two groups. One group received the -Zn diet, and the other received the +Zn diet. Urine collections were obtained from both groups of calves when the -Zn calves showed a decrease (P < .05) in feed efficiency relative to the controls and when they were repleted with 23 mg Zn/kg diet DM from ZnSO4 and their feed efficiency had returned to that of the controls. Urinary 3-methylhistidine indicated that -Zn calves had less (P < .05) daily protein degradation than the controls. Refeeding Zn to the -Zn group did not change BW or daily protein degradation. Results indicated that a marginal Zn deficiency decreased fractional accretion rate, increased (P < .05) urine excretion, and tended to increase (P < .19) Na and decrease (P < .12) K concentrations in the urine.
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Preliminary voice and speech analysis following fetal dopamine transplants in 5 individuals with Parkinson disease. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 1997; 40:615-626. [PMID: 9210118 DOI: 10.1044/jslhr.4003.615] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A surgical procedure involving transplantation of fetal dopamine cells into the striatum of persons with advanced Parkinson disease (PD) has recently been performed in an attempt to alleviate Parkinsonian and drug-dose related symptoms (e.g., the "on-off" phenomena). Improvements in limb motor and neurological function, as well as less severe and shorter on-off episodes have been reported following fetal cell transplant (FCT) surgery. Acoustic, electroglottographic, and perceptual measures were analyzed pre- and post-surgery to determine if phonotory and articulatory function were affected by this relatively new form of treatment. In addition, speech and motor exam measures were compared to determine if similar directional changes across motor systems were apparent. Findings suggest that FCT surgery did not systematically influence voice and speech production. Also, it appears that FCT surgery may differentially affect phonatory, articulatory, and limb motor systems. Findings are discussed relative to these differential effects.
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Abstract
A 12-week experiment was conducted to compare supplemental ZnMet, ZnSO4, and ZnO on Zn, Cu and metallothionein (MT) concentrations in various fluids and tissues of 32 yearling cattle. Supplemental Zn (360 mg per day) was fed for four weeks, withdrawn for four weeks, and then resumed for another four weeks. Mineral (Zn and Cu) concentrations were determined in serum, liver, pancreas, kidney, bone, bone marrow (metacarpus), hair, hoof and neck muscle (sterno mandibularis), and Zn only in erythrocytes, skin and cornea. Metallothionein levels were determined in liver, pancreas and kidney. There were no treatment differences (p > 0.05) in serum or erythrocyte Zn content for all days of collection. Serum Cu concentrations tended to decrease with all treatments. There were no treatment differences (p > 0.05) in Zn and Cu tissue concentrations and liver, kidney and pancreas MT concentrations. Tissue Cu concentrations did not drop in the supplemented treatments when compared to controls. At adequate levels of dietary Zn, bioavailability of supplemental Zn sources may be less important than under conditions of limited dietary Zn or if very high levels of supplemental Zn are fed.
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Abstract
A study was conducted to compare bioavailability, interactions and retention of different sources of Zn and Cu fed to rats. Sixty-three male CD rats were fed individually a purified diet and deionized water ad libitum. The nine treatments included were all combinations of three Zn (ZnMet, ZnLys, ZnSO4) and three Cu (CuLys, CuSO4, CuO) sources added to the basal diet at 30 mg/kg of Zn and 6 mg/kg of Cu forming a 3' 3 factorial experiment. After the four-week supplementation phase, four randomly selected rats from each treatment were sacrificed (Phase 1). The remaining rats were fed the purified, unsupplemented diet for an additional week (Phase 2) and then sacrificed. Mineral (Zn and Cu) concentrations were determined in plasma, liver, kidney, bone and muscle, and metallothionein (MT) content was determined in liver and kidney. Plasma Cu concentrations were lower (p < 0.05) for CuO-than CuSO4- and CuLys-supplemented rats. Bone Zn concentrations were higher (p < 0.05) for CuLys-than for CuO-supplemented rats. In all tissues where Cu was measured, CuO was the lowest (p < 0.05) available source of Cu. Furthermore, in muscle, CuSO4-supplemented rats had higher (p < 0.05) Cu concentrations than CuLys-supplemented rats. Kidney MT concentrations followed the same pattern as Cu concentrations, with CuO-fed rats having the lowest (p < 0.05) MT concentrations. Plasma Cu concentrations of depleted rats were lower (p < 0.05) for CuO-than CuLys-supplemented rats. Kidney Zn concentrations were lower (p < 0.05) for CuSO4-than for CuO-supplemented rats after depletion. In liver, CuO supplemented rats had the lowest (p < 0.05) Cu concentration. Copper oxide was less available than CuLys and CuSO4 when added in adequate dietary levels. However, organic (ZnMet and ZnLys) and inorganic (ZnSO4) sources of Zn were similar.
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Identification and expression of eight novel mutations among non-Jewish patients with Canavan disease. Am J Hum Genet 1996; 59:95-102. [PMID: 8659549 PMCID: PMC1915091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Canavan disease is inherited as an autosomal recessive trait that is caused by the deficiency of aspartoacylase (ASPA). The majority of patients with Canavan disease are from an Ashkenazi Jewish background. Mutations in ASPA that lead to loss of enzymatic activity have been identified, and E285A and Y231X are the two predominant mutations that account for 97% of the mutant chromosomes in Ashkenazi Jewish patients. The current study was aimed at finding the molecular basis of Canavan disease in 25 independent patients of non-Jewish background. Eight novel and three previously characterized mutations accounted for 80% (40/50) of mutant chromosomes. The A305E missense mutation accounted for 48% (24/50) of mutant chromosomes in patients of western European descent, while the two predominant Jewish mutations each accounted for a single mutant chromosome. The eight novel mutations identified included 1- and 4-bp deletions (32 deltaT and 876 deltaAGAA, respectively) and I16T, G27R, D114E, G123E, C152Y, and R168C missense mutations. The homozygous 32 deltaT deletion was identified in the only known patient of African-American origin with Canavan disease. The heterozygosity for 876 deltaAGAA mutation was identified in three independent patients from England. Six single-base changes leading to missense mutations were identified in patients from Turkey (D114E, R168C), The Netherlands (I16T), Germany (G27R), Ireland (C152Y), and Canada (G123E). A PCR-based protocol is described that was used to introduce mutations in wild-type cDNA. In vitro expression of mutant cDNA clones demonstrated that all of these mutations led to a deficiency of ASPA and should therefore result in Canavan disease.
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