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1.
Ear Hear ; 45(4): 894-904, 2024.
Article in English | MEDLINE | ID: mdl-38334699

ABSTRACT

OBJECTIVES: The Montreal Cognitive Assessment (MoCA) is a cognitive screening tool that has 4 of 10 test items heavily dependent on auditory input, potentially leaving hearing-impaired (HI) individuals at a disadvantage. Previous work found that HI individuals scored lower than normal-hearing (NH) individuals on the MoCA, potentially attributed to the degraded auditory signals negatively impacting the ability to commit auditory information to memory. However, there is no research comparing how cochlear implant (CI) recipients perform on the MoCA relative to NH and HI individuals. This study aimed to (1) examine the effect of implementing three different hearing-adjusted scoring methods for a group of age-matched CI recipients and NH individuals, (2) determine if there is a difference between the two groups in overall scores and hearing-adjusted scores, and (3) compare scores across our CI and NH data to the published HI data for all scoring methods. We hypothesized that (1) scores for CI recipients would improve with implementation of the hearing-adjusted scoring methods over the original method, (2) CI recipients would score lower than NH participants for both original and adjusted scoring methods, and (3) the difference in scores between NH and CI listeners for both adjusted and unadjusted scores would be greater than that reported in the literature between NH and HI individuals due to the greater severity of hearing loss and relatively poor spectral resolution of CIs. DESIGN: A total of 94 adults with CIs and 105 adults with NH were initially enrolled. After age-matching the two groups and excluding those who self-identified as NH but failed a hearing screening, a total of 75 CI participants (mean age 61.2 y) and 74 NH participants (mean age 58.8 y) were administered the MoCA. Scores were compared between the NH and CI groups, as well as to published HI data, using the original MoCA scoring method and three alternative scoring methods that excluded various auditory-dependent test items. RESULTS: MoCA scores improved for all groups when two of the three alternative scoring methods were used, with no significant interaction between scoring method and group. Scores for CI recipients were significantly poorer than those for age-matched NH participants for all scoring methods. CI recipients scored better than the published data for HI individuals; however, the HI group was not age matched to the CI and NH groups. CONCLUSIONS: MoCA scores are only partly affected by the potentially greater cognitive processing required to interpret degraded auditory signals. Even with the removal of the auditory-dependent items, CI recipients still did not perform as well as the age-matched NH group. Importantly, removing auditory-dependent items significantly and fundamentally alters the test, thereby reducing its sensitivity. This has important limitations for administration and interpretation of the MoCA for people with hearing loss.


Subject(s)
Cochlear Implants , Mental Status and Dementia Tests , Humans , Male , Female , Middle Aged , Aged , Adult , Case-Control Studies , Hearing Loss/rehabilitation , Cochlear Implantation , Aged, 80 and over
2.
Am J Ther ; 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37820082

ABSTRACT

BACKGROUND: Loop diuretic therapy effectively treats edema related to heart failure, chronic kidney disease, and liver impairment; however, evidence supporting other indications is lacking. For indications such as hypertension or dependent edema or treatment of adverse events associated with other medications, the benefits likely do not outweigh the risks, putting patients at an unacceptably high risk of poor outcomes. STUDY QUESTION: What is the proportion of loop diuretic prescribing that occurs in the absence of a diagnosis of heart failure, chronic kidney disease, liver impairment, or other evidence-based indications? STUDY DESIGN: This was a national, retrospective, cross-sectional investigation conducted using the National Ambulatory Care Survey from 2013 to 2016. Outpatient visits for patients aged 18 years or older prescribed with loop diuretics were included. MEASURES AND OUTCOMES: The primary end point was the frequency of potentially inappropriate loop diuretic prescribing. The secondary end point was a multivariable regression model that identified predictors of potentially inappropriate loop diuretic utilization. RESULTS: This analysis identified 5261 outpatient visits conducted during the study period in which loop diuretics were prescribed. Of these, 3648 visits (65.8% of weighted visits) were of patients without a history of heart failure, chronic kidney disease, or liver impairment. Positive predictors included age older than 65 years (odds ratio [OR] 1.71; 95% confidence interval [CI] 1.38-2.13), concomitant calcium channel blocker (OR 1.42; 95% CI, 1.09-1.84), sodium-containing medication use (OR 2.78; 95% CI, 1.23-6.25), and office visit with a cardiology specialist (OR 2.84; 95% CI, 2.31-3.50). CONCLUSIONS: This analysis identified that loop diuretics are prescribed in the absence of evidence-based indications more frequently than they are prescribed for them. This prescribing pattern creates a unique opportunity for clinicians to optimize patient care. Further study of the outcomes associated with this prescribing pattern is warranted.

3.
Environ Sci Pollut Res Int ; 30(6): 15392-15399, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36169821

ABSTRACT

There is increasing awareness of the negative ecological and environmental effects of widespread use of pesticides on the landscape. Spillover or drift of pesticides from agricultural areas has been shown to impact species health, reproduction, and trophic dynamics through both direct and indirect mechanisms. Neonicotinoid insecticides are associated with observed declines of insectivorous and grassland birds, and these environmental pollutants are a significant conservation concern for many species that have experienced past or current population declines. Due to the high efficacy of these modern insecticides in depressing local insect populations, insectivorous birds can be negatively impacted by a pesticide-mediated reduction in food supply. Neonicotinoids may act synergistically with other stressors, such as habitat loss, to exacerbate threats to species or population viability. The Tricolored Blackbird is an insectivorous grassland bird of conservation concern in California, USA. Due to the high association of this species with agricultural habitats, we sought to quantify the amount of neonicotinoid residues in Tricolored Blackbird carcasses as a first step in assessing how this species may be impacted by pesticides. Out of 85 salvaged carcasses sampled (N = 24 adults, N = 3 fledglings, and N = 58 nestlings), only two contained detectable levels of target compounds. These were an adult and one nestling that contained clothianidin residue (40 ppb and 7 ppb, respectively); both of these birds were salvaged from breeding colonies associated with dairy farms in Kern County, California. We suggest that further work is needed to assess neonicotinoid exposure of Tricolored Blackbirds in dairy-associated breeding colonies.


Subject(s)
Insecticides , Pesticides , Songbirds , Animals , Plant Breeding , Neonicotinoids
4.
Life Sci Alliance ; 6(1)2023 01.
Article in English | MEDLINE | ID: mdl-36241425

ABSTRACT

New therapeutic targets are a valuable resource for treatment of SARS-CoV-2 viral infection. Genome-wide association studies have identified risk loci associated with COVID-19, but many loci are associated with comorbidities and are not specific to host-virus interactions. Here, we identify and experimentally validate a link between reduced expression of EXOSC2 and reduced SARS-CoV-2 replication. EXOSC2 was one of the 332 host proteins examined, all of which interact directly with SARS-CoV-2 proteins. Aggregating COVID-19 genome-wide association studies statistics for gene-specific eQTLs revealed an association between increased expression of EXOSC2 and higher risk of clinical COVID-19. EXOSC2 interacts with Nsp8 which forms part of the viral RNA polymerase. EXOSC2 is a component of the RNA exosome, and here, LC-MS/MS analysis of protein pulldowns demonstrated interaction between the SARS-CoV-2 RNA polymerase and most of the human RNA exosome components. CRISPR/Cas9 introduction of nonsense mutations within EXOSC2 in Calu-3 cells reduced EXOSC2 protein expression and impeded SARS-CoV-2 replication without impacting cellular viability. Targeted depletion of EXOSC2 may be a safe and effective strategy to protect against clinical COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/genetics , Chromatography, Liquid , Codon, Nonsense , DNA-Directed RNA Polymerases/genetics , Exosome Multienzyme Ribonuclease Complex/genetics , Genome-Wide Association Study , Humans , RNA, Viral/metabolism , RNA-Binding Proteins/genetics , SARS-CoV-2/genetics , Tandem Mass Spectrometry , Viral Replicase Complex Proteins , Virus Replication/genetics
5.
Proc Biol Sci ; 289(1982): 20220991, 2022 09 14.
Article in English | MEDLINE | ID: mdl-36100019

ABSTRACT

Nuanced understanding of seasonal movements of partially migratory birds is paramount to species and habitat conservation. Using nascent statistical methods, we identified migratory strategies of birds outfitted with radio-frequency identification (RFID) tags detected at RFID feeders in two sites in California, USA. We quantified proportions of migrants and residents and the seasonal phenology for each movement strategy in Allen's and Anna's hummingbirds; we also validated our methodology by fitting our model to obligate migratory black-chinned hummingbirds. Allen's and Anna's hummingbirds exhibited characteristics of facultative migratory behaviour. We also quantified apparent annual survival for each migratory strategy and found that residents had significantly higher probabilities of apparent survival. Low survival estimates for migrants suggest that a high proportion of birds in the migrant group permanently emigrated from our study sites. Considered together, our analyses suggest that hummingbirds in both northern and southern California sites partake in diverse and highly plastic migratory behaviours. Our assessment elucidates the dynamics underlying idiosyncratic migratory behaviours of two species of hummingbirds, in addition to describing a framework for similar assessments of migratory behaviours using the multi-state open robust design with state uncertainty model and single-site dynamics.


Subject(s)
Animal Migration , Birds , Animals , Ecosystem
6.
Life Sci Alliance ; 5(9)2022 09.
Article in English | MEDLINE | ID: mdl-35568435

ABSTRACT

Dipeptide repeat (DPR) proteins are aggregation-prone polypeptides encoded by the pathogenic GGGGCC repeat expansion in the C9ORF72 gene, the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. In this study, we focus on the role of poly-GA DPRs in disease spread. We demonstrate that recombinant poly-GA oligomers can directly convert into solid-like aggregates and form characteristic ß-sheet fibrils in vitro. To dissect the process of cell-to-cell DPR transmission, we closely follow the fate of poly-GA DPRs in either their oligomeric or fibrillized form after administration in the cell culture medium. We observe that poly-GA DPRs are taken up via dynamin-dependent and -independent endocytosis, eventually converging at the lysosomal compartment and leading to axonal swellings in neurons. We then use a co-culture system to demonstrate astrocyte-to-motor neuron DPR propagation, showing that astrocytes may internalise and release aberrant peptides in disease pathogenesis. Overall, our results shed light on the mechanisms of poly-GA cellular uptake and propagation, suggesting lysosomal impairment as a possible feature underlying the cellular pathogenicity of these DPR species.


Subject(s)
Amyotrophic Lateral Sclerosis , C9orf72 Protein , Frontotemporal Dementia , Amyotrophic Lateral Sclerosis/pathology , C9orf72 Protein/genetics , Dipeptides , Frontotemporal Dementia/genetics , Frontotemporal Dementia/metabolism , Frontotemporal Dementia/pathology , Humans , Motor Neurons/metabolism
7.
Life Sci Alliance ; 5(8)2022 08.
Article in English | MEDLINE | ID: mdl-35440492

ABSTRACT

Spinal muscular atrophy, the leading genetic cause of infant mortality, is a motor neuron disease caused by low levels of survival motor neuron (SMN) protein. SMN is a multifunctional protein that is implicated in numerous cytoplasmic and nuclear processes. Recently, increasing attention is being paid to the role of SMN in the maintenance of DNA integrity. DNA damage and genome instability have been linked to a range of neurodegenerative diseases. The ribosomal DNA (rDNA) represents a particularly unstable locus undergoing frequent breakage. Instability in rDNA has been associated with cancer, premature ageing syndromes, and a number of neurodegenerative disorders. Here, we report that SMN-deficient cells exhibit increased rDNA damage leading to impaired ribosomal RNA synthesis and translation. We also unravel an interaction between SMN and RNA polymerase I. Moreover, we uncover an spinal muscular atrophy motor neuron-specific deficiency of DDX21 protein, which is required for resolving R-loops in the nucleolus. Taken together, our findings suggest a new role of SMN in rDNA integrity.


Subject(s)
Motor Neurons , Muscular Atrophy, Spinal , DEAD-box RNA Helicases/metabolism , DNA Damage/genetics , DNA, Ribosomal/genetics , DNA, Ribosomal/metabolism , Humans , Infant , Motor Neurons/metabolism , Muscular Atrophy, Spinal/genetics , Muscular Atrophy, Spinal/metabolism , Ribosomes/genetics , Ribosomes/metabolism
8.
bioRxiv ; 2022 Mar 07.
Article in English | MEDLINE | ID: mdl-35291294

ABSTRACT

New therapeutic targets are a valuable resource in the struggle to reduce the morbidity and mortality associated with the COVID-19 pandemic, caused by the SARS-CoV-2 virus. Genome-wide association studies (GWAS) have identified risk loci, but some loci are associated with co-morbidities and are not specific to host-virus interactions. Here, we identify and experimentally validate a link between reduced expression of EXOSC2 and reduced SARS-CoV-2 replication. EXOSC2 was one of 332 host proteins examined, all of which interact directly with SARS-CoV-2 proteins; EXOSC2 interacts with Nsp8 which forms part of the viral RNA polymerase. Lung-specific eQTLs were identified from GTEx (v7) for each of the 332 host proteins. Aggregating COVID-19 GWAS statistics for gene-specific eQTLs revealed an association between increased expression of EXOSC2 and higher risk of clinical COVID-19 which survived stringent multiple testing correction. EXOSC2 is a component of the RNA exosome and indeed, LC-MS/MS analysis of protein pulldowns demonstrated an interaction between the SARS-CoV-2 RNA polymerase and the majority of human RNA exosome components. CRISPR/Cas9 introduction of nonsense mutations within EXOSC2 in Calu-3 cells reduced EXOSC2 protein expression, impeded SARS-CoV-2 replication and upregulated oligoadenylate synthase ( OAS) genes, which have been linked to a successful immune response against SARS-CoV-2. Reduced EXOSC2 expression did not reduce cellular viability. OAS gene expression changes occurred independent of infection and in the absence of significant upregulation of other interferon-stimulated genes (ISGs). Targeted depletion or functional inhibition of EXOSC2 may be a safe and effective strategy to protect at-risk individuals against clinical COVID-19.

9.
PLoS One ; 15(1): e0227333, 2020.
Article in English | MEDLINE | ID: mdl-31952076

ABSTRACT

The valley elderberry longhorn beetle (VELB), Desmocerus californicus dimorphus (Coleoptera: Cerambycidae), is a federally threatened subspecies endemic to the Central Valley of California. The VELB range partially overlaps with that of its morphologically similar sister taxon, the California elderberry longhorn beetle (CELB), Desmocerus californicus californicus (Coleoptera: Cerambycidae). Current surveying methods are limited to visual identification of larval exit holes in the VELB/CELB host plant, elderberry (Sambucus spp.), into which larvae bore and excavate feeding galleries. Unbiased genetic approaches could provide a much-needed complementary approach that has more precision than relying on visual inspection of exit holes. In this study we developed a DNA sequencing-based method for indirect detection of VELB/CELB from frass (insect fecal matter), which can be easily and non-invasively collected from exit holes. Frass samples were collected from 37 locations and the 12S and 16S mitochondrial genes were partially sequenced using nested PCR amplification. Three frass-derived sequences showed 100% sequence identity to VELB/CELB barcode references from museum specimens sequenced for this study. Database queries of frass-derived sequences also revealed high similarity to common occupants of old VELB feeding galleries, including earwigs, flies, and other beetles. Overall, this non-invasive approach is a first step towards a genetic assay that could augment existing VELB monitoring and accurately discriminate between VELB, CELB, and other insects. Furthermore, a phylogenetic analysis of 12S and 16S data from museum specimens revealed evidence for the existence of a previously unrecognized, genetically distinct CELB subpopulation in southern California.


Subject(s)
Coleoptera/genetics , Ecosystem , Environmental Monitoring , Larva/genetics , Animals , California , Coleoptera/physiology , DNA, Mitochondrial/genetics , Endangered Species , Humans , Larva/physiology , Phylogeny , Sequence Analysis, DNA
10.
Environ Sci Pollut Res Int ; 26(15): 15458-15466, 2019 May.
Article in English | MEDLINE | ID: mdl-30941712

ABSTRACT

External feather rinses and homogenized whole-carcass tissue matrix from two hummingbird species found in California (Calypte anna and Archilochus alexandri) were analyzed for the presence of nine insecticides commonly used in urban settings. Using a liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analytical method, samples were quantitatively tested for the following neonicotinoids: dinotefuran, nitenpyram, thiamethoxam, acetamiprid, thiacloprid, clothianidin, imidacloprid, and sulfoxaflor. This analytical method was also used to qualitatively screen for the presence of approximately 150 other pesticides, drugs, and natural products. Feather rinsates from both hummingbird species had detectable concentrations of carbamate and neonicotinoid classes of insecticides. Combined results of the rinsate and homogenized samples (n = 64 individual hummingbirds) showed that 44 individuals (68.75%) were positive for one to four target compounds. This study documented that hummingbirds found in California are exposed to insecticides. Furthermore, feather rinsates and carcass homogenates are matrices that can be used for assessing pesticide exposure in small bird species. The small body size of hummingbirds limits traditional sampling methods for tissues and whole blood to evaluate for pesticide exposure. Thus, utilization of this analytical method may facilitate future research on small-sized avian species, provide insight into pesticide exposure, and ultimately lead to improved conservation of hummingbirds.


Subject(s)
Chromatography, Liquid/methods , Insecticides/analysis , Tandem Mass Spectrometry/methods , Animals , Birds , California , Feathers/chemistry , Guanidines/chemistry , Neonicotinoids/chemistry , Nitro Compounds/chemistry , Pyridines/chemistry , Sulfur Compounds/chemistry , Thiamethoxam/chemistry , Thiazines/chemistry , Thiazoles
11.
J Vet Diagn Invest ; 31(3): 399-407, 2019 May.
Article in English | MEDLINE | ID: mdl-30853007

ABSTRACT

We developed and validated a liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analytical method for quantitatively measuring pesticide concentrations in small-body avian tissue samples using homogenized 1-2-d-old chicken carcasses as the test matrix. We quantified the following key insecticides: sulfoxaflor (sulfoximine class) and the neonicotinoids dinotefuran, nitenpyram, thiamethoxam, acetamiprid, thiacloprid, clothianidin, and imidacloprid. We used fortified chick carcass samples to validate method accuracy (80-125% recoveries), precision (<20% relative standard deviation), and sensitivity (≤1.2 ppb) for these targeted analytes. This method also uses full-scan, high-resolution MS to screen for the presence of a wide variety of other xenobiotics in bird carcasses. The utility of our screening process was demonstrated by the detection of carbaryl in some samples. This sensitive LC-HRMS analytical method for insecticide detection in a matrix of homogenized carcass is ideal for evaluating small birds for insecticide exposure. This novel whole-carcass method may allow for research studies of small-bodied, free-ranging avian species, and could provide insight regarding their exposure to multiple classes of environmental contaminants.


Subject(s)
Chickens , Drug Residues/chemistry , Insecticides/chemistry , Neonicotinoids/chemistry , Xenobiotics/chemistry , Animals , Chromatography, High Pressure Liquid/methods , Limit of Detection , Tandem Mass Spectrometry
12.
J Binocul Vis Ocul Motil ; 69(1): 13-17, 2019.
Article in English | MEDLINE | ID: mdl-30806169

ABSTRACT

PURPOSE: We report the first case of congenital ocular neuromyotonia (ONM) and the results of strabismus surgery for this patient's co-existing cranial nerve (CN) III palsy. PATIENTS AND METHOD: The patient presented at 18 months with strabismus that had reportedly been present since the time of birth. On exam, she had persistent exotropia (RXT) and hypertropia (RHT) with episodes of esotropia in the right eye that could be evoked by sustained left gaze. A diagnosis of ONM with partial CN III palsy was made. T1-weighted, T2-weighted, and fluid-attenuated inversion recovery magnetic resonance imaging failed to reveal intracranial pathology. RESULTS: Gaze induced intermittent esotropia resolved with carbamazepine. Surgery was performed to improve the patient's RXT and RHT. Post-operatively, the patient's RXT had improved from 12 to 15 prism diopters (∆) at near and 20∆ at a distance to 10∆ RXT at near with no horizontal deviation at distance. Her deviation has remained stable for 13 years, as has her neurological exam and good state of health. CONCLUSION: This case demonstrates that ONM may present congenitally and adds to the body of knowledge regarding surgical outcomes on concurrent CN palsies in these patients.


Subject(s)
Isaacs Syndrome/congenital , Oculomotor Nerve Diseases/congenital , Strabismus/congenital , Carbamazepine/therapeutic use , Eye Movements , Female , Humans , Infant , Isaacs Syndrome/diagnosis , Isaacs Syndrome/therapy , Oculomotor Muscles/innervation , Oculomotor Nerve Diseases/diagnosis , Oculomotor Nerve Diseases/surgery , Ophthalmologic Surgical Procedures , Sodium Channel Blockers/therapeutic use , Strabismus/diagnosis , Strabismus/therapy
13.
PLoS One ; 13(2): e0191323, 2018.
Article in English | MEDLINE | ID: mdl-29444089

ABSTRACT

Proctophyllodes huitzilopochtlii Atyeo & Braasch 1966 (Acariformes: Astigmata: Proctophyllodidae), a feather mite, was found on feathers collected from five hummingbird species in California. This mite has not been previously documented on feathers from Anna's (Calypte anna [Lesson 1829]) or Black-chinned (Archilochus alexandri [Bourcier & Mulsant 1846]) Hummingbirds. A total of 753 hummingbirds were evaluated for the presence of mites by species (Allen's n = 112; Anna's n = 500; Black-chinned n = 122; Rufous n = 18; Calliope n = 1), sex (males n = 421; females n = 329; 3 unidentified), and age (juvenile n = 199; after-hatch-year n = 549; 5 unidentified). Of these 753 hummingbirds evaluated, mites were present on the rectrices of 40.9% of the birds. Significantly more Anna's Hummingbirds were positive for rectricial mites (59.2%) compared with 8.2% of Black-chinned, 0.9% of Allen's, 5.6% of Rufous Hummingbirds, and 0% for Calliope (p-value < 0.0001). Across all hummingbird species, male hummingbirds (44.9%) had a higher prevalence of rectricial mites compared to female hummingbirds (36.2%; p-value = 0.004), while juvenile hummingbirds (46.2%) had a non-significantly higher prevalence compared to after-hatch-year hummingbirds (39.0%; p-value = 0.089). On average, the percentage of the long axis of the rachis occupied by mites for the outer rectrices (R4 and R5) was 19%, compared to 11% for inner rectrices (R1 and R2), a significant difference (p-value = <0.0001). There was a marginal lack of significance for symmetrical distribution of tail mites with the mean left side percentage of long axis of the rachis occupied by mites being 16% and very close to the mean right side score of 18% (p-value = 0.003). The identification of the feather mite species was based on light microscopic morphometry, and mite distribution on feathers was further evaluated using tabletop scanning electron microscopy (TSEM). The hummingbird-feather mite relationship is not well understood, but the specialized TSEM technique may be especially useful in examining natural positioning and developmental aspects of the mites since it allows in situ feather examination of live mites.


Subject(s)
Birds/parasitology , Feathers/parasitology , Mites/classification , Animals , California , Female , Flight, Animal , Male , Microscopy/methods , Microscopy, Electron, Scanning/methods , Mites/genetics , Mites/pathogenicity , Prevalence
14.
J AAPOS ; 19(6): 526-30, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26691031

ABSTRACT

PURPOSE: To report our experince in establishing a sustainable pediatric surgical outreach mission to an underserved population in Guatemala for treatment of strabismic disorders. METHODS: A pediatric ophthalmic surgical outreach mission was established. Children were evaluated for surgical intervention by 3 pediatric ophthalmologists and 2 orthoptists. Surgical care was provided at the Moore Pediatric Surgery Center, Guatemala City, over 4 days. Postoperative care was facilitated by Guatemalan physicians during the second year. RESULTS: In year 1, patients 1-17 years of age were referred by local healthcare providers. In year 2, more than 60% of patients were prescreened by a local pediatric ophthalmologist. We screened 47% more patients in year 2 (132 vs 90). Diagnoses included congenital and acquired esotropia, consecutive and acquired exotropia, congenital nystagmus, Duane syndrome, Brown syndrome, cranial nerve palsy, dissociated vertical deviation, and oblique muscle dysfunction. Overall, 42% of the patients who were screened underwent surgery. We performed 21 more surgeries in our second year (58 vs 37), a 57% increase. There were no significant intra- or postoperative complications. CONCLUSIONS: Surgical outreach programs for children with strabismic disorders in the developing world can be established through international cooperation, a multidisciplinary team of healthcare providers, and medical equipment allocations. Coordinating care with local pediatric ophthalmologists and medical directors facilitates best practice management for sustainability.


Subject(s)
Community-Institutional Relations , Developing Countries , Medical Missions/organization & administration , Ophthalmologic Surgical Procedures , Patient Care Team/organization & administration , Strabismus/surgery , Adolescent , Child , Child, Preschool , Female , Guatemala , Humans , Infant , Male , Pediatrics , Vulnerable Populations
16.
PLoS One ; 9(5): e96980, 2014.
Article in English | MEDLINE | ID: mdl-24817307

ABSTRACT

In metapopulations in which habitat patches vary in quality and occupancy it can be complicated to calculate the net time-averaged contribution to reproduction of particular populations. Surprisingly, few indices have been proposed for this purpose. We combined occupancy, abundance, frequency of occurrence, and reproductive success to determine the net value of different sites through time and applied this method to a bird of conservation concern. The Tricolored Blackbird (Agelaius tricolor) has experienced large population declines, is the most colonial songbird in North America, is largely confined to California, and breeds itinerantly in multiple habitat types. It has had chronically low reproductive success in recent years. Although young produced per nest have previously been compared across habitats, no study has simultaneously considered site occupancy and reproductive success. Combining occupancy, abundance, frequency of occurrence, reproductive success and nest failure rate we found that that large colonies in grain fields fail frequently because of nest destruction due to harvest prior to fledging. Consequently, net time-averaged reproductive output is low compared to colonies in non-native Himalayan blackberry or thistles, and native stinging nettles. Cattail marshes have intermediate reproductive output, but their reproductive output might be improved by active management. Harvest of grain-field colonies necessitates either promoting delay of harvest or creating alternative, more secure nesting habitats. Stinging nettle and marsh colonies offer the main potential sources for restoration or native habitat creation. From 2005-2011 breeding site occupancy declined 3x faster than new breeding colonies were formed, indicating a rapid decline in occupancy. Total abundance showed a similar decline. Causes of variation in the value for reproduction of nesting substrates and factors behind continuing population declines merit urgent investigation. The method we employ should be useful in other metapopulation studies for calculating time-averaged reproductive output for different sites.


Subject(s)
Breeding , Ecosystem , Passeriformes/physiology , Reproduction , Animals , Longevity , Population Density , Time Factors
17.
Ecol Evol ; 3(9): 2845-58, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24101977

ABSTRACT

Population trends represent a minimum amount of information required to assess the conservation status of a species. However, understanding and detecting trends can be complicated by variation among habitats and regions, and by dispersal connecting habitats through source-sink dynamics. We analyzed trends in breeding populations between habitats and regions to better understand the overall dynamics of a species' decline. Specifically, we analyzed historical trends in breeding populations of tricolored blackbirds (Agelaius tricolor) using breeding records from 1907 to 2009. The species breeds itinerantly and ephemerally uses multiple habitat types and breeding areas, which make interpretation of trends complex. We found overall abundance declines of 63% between 1935 and 1975. Since 1980 overall declines became nonsignificant and obscure despite large amounts of data from 1980 to 2009. Temporal trends differed between breeding habitat types and were associated with regional differences in population declines. A new habitat, triticale crops (a wheat-rye hybrid grain) produced colonies 40× larger, on average, than other breeding habitats, and contributed to a change in regional distribution since it primarily occurred in a single region. The mechanism for such an effect is not clear, but could represent the local availability of foodstuffs in the landscape rather than something specific to triticale crops. While variation in trends among habitats clearly occurred, they could not easily be ascribed to source-sink dynamics, ecological traps, habitat selection or other detailed ecological mechanisms. Nonetheless, such exchanges provide valuable information to guide management of dynamic systems.

19.
Neurotherapeutics ; 9(4): 801-13, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22270809

ABSTRACT

Advances in the understanding of the endogenous cannabinoid system have led to several therapeutic indications for new classes of compounds that enhance cannabinergic responses. Endocannabinoid levels are elevated during pathogenic conditions, and inhibitors of endocannabinoid inactivation promote such on-demand responses. The endocannabinoids anandamide and 2-arachidonoyl glycerol have been implicated in protective signaling against excitotoxic episodes, including seizures. To better understand modulatory pathways that can exploit such responses, we used the new generation compound AM6701 that blocks both the anandamide-deactivating enzyme fatty acid amide hydrolase (FAAH) and the 2-arachidonoyl glycerol-deactivating enzyme monoacylglycerol lipase (MAGL) with equal potency. Also studied was the structural isomer AM6702 which is 44-fold more potent for inhibiting FAAH versus MAGL. When applied before and during kainic acid (KA) exposure to cultured hippocampal slices, AM6701 protected against the resulting excitotoxic events of calpain-mediated cytoskeletal damage, loss of presynaptic and postsynaptic proteins, and pyknotic changes in neurons. The equipotent inhibitor was more effective than its close relative AM6702 at protecting against the neurodegenerative cascade assessed in the slice model. In vivo, AM6701 was also the more effective compound for reducing the severity of KA-induced seizures and protecting against behavioral deficits linked to seizure damage. Corresponding with the behavioral improvements, cytoskeletal and synaptic protection was elicited by AM6701, as found in the KA-treated hippocampal slice model. It is proposed that the influence of AM6701 on FAAH and MAGL exerts a synergistic action on the endocannabinoid system, thereby promoting the protective nature of cannabinergic signaling to offset excitotoxic brain injury.


Subject(s)
Amidohydrolases/antagonists & inhibitors , Endocannabinoids/metabolism , Monoacylglycerol Lipases/antagonists & inhibitors , Neurons/enzymology , Seizures/enzymology , Animals , Convulsants/toxicity , Enzyme Inhibitors/pharmacology , Hippocampus/drug effects , Hippocampus/enzymology , Immunoblotting , Male , Neurons/drug effects , Organ Culture Techniques , Rats , Rats, Sprague-Dawley , Tetrazoles/toxicity
20.
J Gen Psychol ; 134(1): 23-42, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17283853

ABSTRACT

The authors compared emotional memory in younger (aged 18-32 years) and older (aged 59-84 years) adults. Previous researchers who investigated the emotionmemory relationship in younger adults consistently showed that emotional arousal enhances memory for central detail. The present authors' goal was to determine whether a similar effect could be found with older adults. Younger and older adults viewed a series of 12 slides, accompanied by a taped narrative, that showed emotionally arousing or neutral scenes in the middle phase (Slides 5-8). Participants then completed recognition tests that were scored for central detail, peripheral detail, and gist. The results indicated that, although younger adults showed higher performance than older adults did, both groups showed increased memory for central detail. In contrast, the authors found no such enhancement for peripheral detail or gist in either group. These results indicated that the arousal manipulation produced a similar effect on memory in younger and older adults. Furthermore, these results were consistent with the notion of poststimulus elaboration, which is the continued processing of central detail after the termination of an arousing event.


Subject(s)
Aging , Arousal/physiology , Emotions , Memory/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Neuropsychological Tests , Photic Stimulation/methods
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