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1.
Proc Biol Sci ; 291(2015): 20232253, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38228502

ABSTRACT

Kelp forests are threatened by ocean warming, yet effects of co-occurring drivers such as CO2 are rarely considered when predicting their performance in the future. In Australia, the kelp Ecklonia radiata forms extensive forests across seawater temperatures of approximately 7-26°C. Cool-edge populations are typically considered more thermally tolerant than their warm-edge counterparts but this ignores the possibility of local adaptation. Moreover, it is unknown whether elevated CO2 can mitigate negative effects of warming. To identify whether elevated CO2 could improve thermal performance of a cool-edge population of E. radiata, we constructed thermal performance curves for growth and photosynthesis, under both current and elevated CO2 (approx. 400 and 1000 µatm). We then modelled annual performance under warming scenarios to highlight thermal susceptibility. Elevated CO2 had minimal effect on growth but increased photosynthesis around the thermal optimum. Thermal optima were approximately 16°C for growth and approximately 18°C for photosynthesis, and modelled performance indicated cool-edge populations may be vulnerable in the future. Our findings demonstrate that elevated CO2 is unlikely to offset negative effects of ocean warming on the kelp E. radiata and highlight the potential susceptibility of cool-edge populations to ocean warming.


Subject(s)
Kelp , Phaeophyceae , Seawater , Hydrogen-Ion Concentration , Ocean Acidification , Carbon Dioxide , Climate Change , Temperature , Oceans and Seas , Global Warming
2.
Commun Biol ; 6(1): 607, 2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37280329

ABSTRACT

Carbon dioxide removal (CDR) and emissions reduction are essential to alleviate climate change. Ocean macroalgal afforestation (OMA) is a CDR method already undergoing field trials where nearshore kelps, on rafts, are purposefully grown offshore at scale. Dissolved iron (dFe) supply often limits oceanic phytoplankton growth, however this potentially rate-limiting factor is being overlooked in OMA discussions. Here, we determine the limiting dFe concentrations for growth and key physiological functions of a representative kelp species, Macrocystis pyrifera, considered as a promising candidate for OMA. dFe additions to oceanic seawater ranging 0.01-20.2 nM Fe' ‒ Fe' being the sum of dissolved inorganic Fe(III) species ‒ result in impaired physiological functions and kelp mortality. Kelp growth cannot be sustained at oceanic dFe concentrations, which are 1000-fold lower than required by M. pyrifera. OMA may require additional perturbation of offshore waters via dFe fertilisation.


Subject(s)
Kelp , Macrocystis , Iron , Oceans and Seas , Seawater , Carbon Dioxide
3.
J Phycol ; 59(4): 738-750, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37252690

ABSTRACT

Release of dissolved organic carbon (DOC) by seaweed underpins the microbial food web and is crucial for the coastal ocean carbon cycle. However, we know relatively little of seasonal DOC release patterns in temperate regions of the southern hemisphere. Strong seasonal changes in inorganic nitrogen availability, irradiance, and temperature regulate the growth of seaweeds on temperate reefs and influence DOC release. We seasonally surveyed and sampled seaweed at Coal Point, Tasmania, over 1 year. Dominant species with or without carbon dioxide (CO2 ) concentrating mechanisms (CCMs) were collected for laboratory experiments to determine seasonal rates of DOC release. During spring and summer, substantial DOC release (10.06-33.54 µmol C · g DW-1 · h-1 ) was observed for all species, between 3 and 27 times greater than during autumn and winter. Our results suggest that inorganic carbon (Ci ) uptake strategy does not regulate DOC release. Seasonal patterns of DOC release were likely a result of photosynthetic overflow during periods of high gross photosynthesis indicated by variations in tissue C:N ratios. For each season, we calculated a reef-scale net DOC release for seaweed at Coal Point of 7.84-12.9 g C · m-2 · d-1 in spring and summer, which was ~16 times greater than in autumn and winter (0.2-1.0 g C · m-2 · d-1 ). Phyllospora comosa, which dominated the biomass, contributed the most DOC to the coastal ocean, up to ~14 times more than Ecklonia radiata and the understory assemblage combined. Reef-scale DOC release was driven by seasonal changes in seaweed physiology rather than seaweed biomass.


Subject(s)
Phaeophyceae , Seaweed , Seasons , Dissolved Organic Matter , Carbon Cycle , Coal , Oceans and Seas
4.
Case Rep Rheumatol ; 2023: 1178035, 2023.
Article in English | MEDLINE | ID: mdl-37139489

ABSTRACT

Immune-mediated necrotizing myopathy (IMNM) is an increasingly common and serious condition in which autoantibodies attack muscle fibers causing clinically significant muscle weakness, fatigue, and myalgias. Recognizing the clinical presentation of IMNM is difficult but necessary, as rapid intervention decreases morbidity. We present a case of a 53-year-old female with IMNM induced by statin therapy with confirmed anti-3-hydroxy-3-methylglutaryl coenzyme A reductase antibodies present on serologic testing. The patient's statin therapy was halted, and the patient was provided with one dose of methylprednisolone and ongoing therapy with mycophenolate. She showed subsequent slow improvements in her muscle weakness and myalgias. It is important for clinicians to be aware of the possible consequences of statin therapy, as these drugs are generally regarded as benign in the medical community. Clinicians should also be aware that statin-induced myopathy can occur at any time during statin therapy. The condition does not necessarily correlate with beginning a new statin medication, as demonstrated in this case in which the patient was on chronic statin therapy before developing symptoms. Continued clinician education and building the fund of medical knowledge regarding this disease are vital to enable clinicians to recognize this disease and act promptly to reduce patient morbidity and improve outcomes.

5.
Case Reports Hepatol ; 2018: 1269340, 2018.
Article in English | MEDLINE | ID: mdl-30363707

ABSTRACT

Acute liver failure (ALF) can be due to numerous causes and result in fatality or necessitate liver transplantation if left untreated. Possible etiologies of ALF include ischemia, venous obstruction, medications, toxins, autoimmune hepatitis, metabolic and infectious causes including hepatitis A-E, varicella-zoster virus (VZV), cytomegalovirus (CMV), herpes simplex virus (HSV), Epstein-Barr virus (EBV), and adenovirus with VZV being the most rarely reported. Pathognomonic skin lesions facilitate diagnosis of VZV hepatitis, but definitive diagnosis is secured with liver biopsy, tissue histopathology, culture, and specific VZV polymerase chain reaction (PCR). Antiviral treatment with intravenous acyclovir can be effective if initiated in a timely manner; however, comorbidities and complications frequently result in high mortality, especially in immunocompromised hosts as exemplified in this case presentation.

6.
Sch Psychol Q ; 30(2): 229-243, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25286311

ABSTRACT

The present study investigated the effectiveness of peer-mediated check-in/check-out (CICO) on the internalizing behaviors of elementary school students. A nonconcurrent multiple-baseline design across participants was utilized to evaluate the intervention's effectiveness for 3 students in 1st and 2nd grade. Two 5th grade students were trained to implement CICO under the supervision of an adult intervention specialist. The peer-mediated CICO procedure was effective for 2 of the 3 participants as evidenced by moderate to large effect sizes; however, all 3 participants were identified as "at-risk" on a universal screener for internalizing problems. The results suggest peer-mediated CICO may be a resource-efficient Tier II strategy to meet the needs of students engaging in internalizing behavior within a multitiered framework of service delivery.


Subject(s)
Child Behavior Disorders/psychology , Peer Group , Students/psychology , Child , Educational Status , Female , Humans , Internal-External Control , Psychiatric Status Rating Scales , Rural Health , School Health Services , United States
7.
Am J Physiol Lung Cell Mol Physiol ; 306(11): L1026-35, 2014 Jun 01.
Article in English | MEDLINE | ID: mdl-24682449

ABSTRACT

The lungs can undergo irreversible damage from chronic alcohol consumption. Herein, we developed an animal model predisposed for edematous lung injury following chronic ingestion of alcohol to better understand the etiology of alcohol-related disorders. Using animal modeling, alongside high-throughput proteomic and microarray assays, we identified changes in lung protein and transcript in mice and rats, respectively, following chronic alcohol ingestion or a caloric control diet. Liquid chromatography-mass spectrometry identified several mitochondrial-related proteins in which the expression was upregulated following long-term alcohol ingestion in mice. Consistent with these observations, rat gene chip microarray analysis of alveolar cells obtained from animals maintained on a Lieber-DeCarli liquid alcohol diet confirmed significant changes in mitochondrial-related transcripts in the alcohol lung. Transmission electron microscopy revealed significant changes in the mitochondrial architecture in alcohol mice, particularly following lipopolysaccharide exposure. Chronic alcohol ingestion was also shown to worsen mitochondrial respiration, mitochondrial membrane polarization, and NAD(+)-to-NADH ratios in alveolar type 2 cells. In summary, our studies show causal connection between chronic alcohol ingestion and mitochondrial dysfunction, albeit the specific role of each of the mitochondrial-related proteins and transcripts identified in our study requires additional study.


Subject(s)
Alveolar Epithelial Cells/metabolism , Central Nervous System Depressants/toxicity , Ethanol/toxicity , Mitochondria/metabolism , Proteome/metabolism , Alcoholism , Alveolar Epithelial Cells/drug effects , Animals , Cells, Cultured , Female , Lipopolysaccharides/pharmacology , Lung/drug effects , Lung/pathology , Male , Membrane Potential, Mitochondrial , Mice , Mice, Inbred C57BL , Microscopy, Electron, Transmission , Mitochondria/drug effects , Mitochondria/pathology , Mitochondrial Swelling , Oligonucleotide Array Sequence Analysis , Proteome/genetics , Rats , Rats, Sprague-Dawley , Transcriptome/drug effects
8.
Am J Physiol Lung Cell Mol Physiol ; 306(10): L897-914, 2014 May 15.
Article in English | MEDLINE | ID: mdl-24658139

ABSTRACT

In vivo imaging is an important tool for preclinical studies of lung function and disease. The widespread availability of multimodal animal imaging systems and the rapid rate of diagnostic contrast agent development have empowered researchers to noninvasively study lung function and pulmonary disorders. Investigators can identify, track, and quantify biological processes over time. In this review, we highlight the fundamental principles of bioluminescence, fluorescence, planar X-ray, X-ray computed tomography, magnetic resonance imaging, and nuclear imaging modalities (such as positron emission tomography and single photon emission computed tomography) that have been successfully employed for the study of lung function and pulmonary disorders in a preclinical setting. The major principles, benefits, and applications of each imaging modality and technology are reviewed. Limitations and the future prospective of multimodal imaging in pulmonary physiology are also discussed. In vivo imaging bridges molecular biological studies, drug design and discovery, and the imaging field with modern medical practice, and, as such, will continue to be a mainstay in biomedical research.


Subject(s)
Lung Diseases/diagnosis , Lung/pathology , Animals , Humans , Lung/diagnostic imaging , Lung Diseases/diagnostic imaging , Lung Diseases/pathology , Magnetic Resonance Imaging , Optical Imaging , Positron-Emission Tomography , Tomography, X-Ray Computed
9.
Biomed Res Int ; 2013: 470217, 2013.
Article in English | MEDLINE | ID: mdl-23509726

ABSTRACT

Similar to effects of alcohol on the heart, liver, and brain, the effects of ethanol (EtOH) on lung injury are preventable. Unlike other vital organ systems, however, the lethal effects of alcohol on the lung are underappreciated, perhaps because there are no signs of overt pulmonary disorder until a secondary insult, such as a bacterial infection or injury, occurs in the lung. This paper provides overview of the complex changes in the alveolar environment known to occur following both chronic and acute alcohol exposures. Contemporary animal and cell culture models for alcohol-induced lung dysfunction are discussed, with emphasis on the effect of alcohol on transepithelial transport processes, namely, epithelial sodium channel activity (ENaC). The cascading effect of tissue and phagocytic Nadph oxidase (Nox) may be triggered by ethanol exposure, and as such, alcohol ingestion and exposure lead to a prooxidative environment; thus impacting alveolar macrophage (AM) function and oxidative stress. A better understanding of how alcohol changes the landscape of the alveolar epithelium can lead to improvements in treating acute respiratory distress syndrome (ARDS) for which hospitalized alcoholics are at an increased risk.


Subject(s)
Alcohol Drinking/adverse effects , Epithelium/drug effects , Lung/drug effects , Alcoholic Beverages/adverse effects , Alcoholism/physiopathology , Animals , Disease Models, Animal , Epithelium/physiopathology , Ethanol/adverse effects , Humans , Inflammation , Lung/physiopathology , Macrophages, Alveolar/drug effects , Oxidative Stress , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/therapy , Signal Transduction
10.
Appl Environ Microbiol ; 79(4): 1385-92, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23263952

ABSTRACT

One explanation given for the high microbial diversity found in soils is that they contain a large inactive biomass that is able to persist in soils for long periods of time. This persistent microbial fraction may help to buffer the functionality of the soil community during times of low nutrients by providing a reservoir of specialized functions that can be reactivated when conditions improve. A study was designed to test the hypothesis: in soils lacking fresh root or detrital inputs, microbial community composition may persist relatively unchanged. Upon addition of new inputs, this community will be stimulated to grow and break down litter similarly to control soils. Soils from two of the Detrital Input and Removal Treatments (DIRT) at the H. J. Andrews Experimental Forest, the no-input and control treatment plots, were used in a microcosm experiment where Douglas-fir needles were added to soils. After 3 and 151 days of incubation, soil microbial DNA and RNA was extracted and characterized using quantitative PCR (qPCR) and 454 pyrosequencing. The abundance of 16S and 28S gene copies and RNA copies did not vary with soil type or amendment; however, treatment differences were observed in the abundance of archaeal ammonia-oxidizing amoA gene abundance. Analysis of ∼110,000 bacterial sequences showed a significant change in the active (RNA-based) community between day 3 and day 151, but microbial composition was similar between soil types. These results show that even after 12 years of plant litter exclusion, the legacy of community composition was well buffered against a dramatic disturbance.


Subject(s)
Biota , Soil Microbiology , Biomass , DNA/genetics , DNA/isolation & purification , Metagenome , Plant Leaves/metabolism , Pseudotsuga/metabolism , RNA/genetics , RNA/isolation & purification , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 28S/genetics , Real-Time Polymerase Chain Reaction , Sequence Analysis, DNA , Time Factors
11.
J Nematol ; 42(1): 78-83, 2010 Mar.
Article in English | MEDLINE | ID: mdl-22736841

ABSTRACT

Soil carbon (C) dynamics and sequestration are controlled by interactions of chemical, physical and biological factors. These factors include biomass quantity and quality, physical environment and the biota. Management can alter these factors in ways that alter C dynamics. We have focused on a range of managed sites with documented land use change from agriculture or grassland to forest. Our results suggest that interactions of soil type, plant and environment impact soil C sequestration. Above and below ground C storage varied widely across sites. Results were related to plant type and calcium on sandy soils in our Northern sites. Predictors of sequestration were more difficult to detect over the temperature range of 12.4°C in the present study. Accrual of litter under pines in the moist Mississippi site limited C storage in a similar manner to our dry Nebraska site. Pre-planting heterogeneity of agricultural fields such as found in Illinois influences C contents. Manipulation of controls on C sequestration such as species planted or amelioration of soil quality before planting within managed sites could increase soil C to provide gains in terrestrial C storage. Cost effective management would also improve soil C pools positively affecting soil fertility and site productivity.

12.
Environ Sci Technol ; 42(18): 6791-9, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-18853791

ABSTRACT

Microbially mediated anaerobic oxidation of methane (AOM) moderates the input of methane, an important greenhouse gas, to the atmosphere by consuming methane produced in various marine, terrestrial, and subsurface environments. AOM coupled to sulfate reduction has been most extensively studied because of the abundance of sulfate in marine systems, but electron acceptors otherthan sulfate are more energetically favorable. Phylogenetic trees based on 16S rRNA gene clone libraries derived from microbial communities where AOM occurs show evidence of diverse, methanotrophic archaea (ANME) closely associated with sulfate-reducing bacteria, but these organisms have not yet been isolated as pure cultures. Several biochemical pathways for AOM have been proposed, including reverse methanogenesis, acetogenesis, and methylogenesis, and both culture-dependent and independent techniques have provided some clues to howthese communities function. Still, questions remain regarding the diversity, physiology, and metabolic restrictions of AOM-related organisms.


Subject(s)
Bacteria/metabolism , Ecology , Energy Metabolism , Methane/metabolism , Anaerobiosis , Oxidation-Reduction
13.
Eat Behav ; 4(2): 159-71, 2003 Aug.
Article in English | MEDLINE | ID: mdl-15000979

ABSTRACT

The primary goal of this study was to determine the relevance of four self-reported eating behaviors (eating before bedtime, eating between meals, feeling hungry within 3 h of eating, and eating beyond satiation) as risk factors for overweight and obesity. The sample consisted of 35- to 49-year-old, premenopausal African American (n=580) and Caucasian (n=398) women, randomly selected from the membership of a large urban prepaid health plan. Eating beyond satiation was the only behavior associated with body mass index (BMI). The odds of becoming obese increased 6-fold for Caucasian women and 15-fold for African American women who ate beyond satiation everyday compared to those who rarely or never ate beyond satiation. Additionally, eating beyond satiation was also the only eating behavior associated with the age of obesity onset. Focusing on this eating behavior in weight loss programs may be important.

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