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1.
J Cardiovasc Electrophysiol ; 34(11): 2286-2295, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37681321

ABSTRACT

INTRODUCTION: Prediction of recurrent ventricular arrhythmia (VA) in survivors of an out-of-hospital cardiac arrest (OHCA) is important, but currently difficult. Risk of recurrence may be related to presence of myocardial scarring assessed with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Our study aims to characterize myocardial scarring as defined by LGE-CMR in survivors of a VA-OHCA and investigate its potential role in the risk of new VA events. METHODS: Between 2015 and 2022, a total of 230 VA-OHCA patients without ST-segment elevation myocardial infarction had CMR before implantable cardioverter-defibrillator implantation for secondary prevention at Copenhagen University Hospital, Rigshospitalet, and Hospital Clínic, University of Barcelona, of which n = 170 patients had a conventional (no LGE protocol) CMR and n = 60 patients had LGE-CMR (including LGE protocol). Scar tissue including core, border zone (BZ) and BZ channels were automatically detected by specialized investigational software in patients with LGE-CMR. The primary endpoint was recurrent VA. RESULTS: After exclusion, n = 52 VA-OHCA patients with LGE-CMR and a mean left ventricular ejection fraction of 49 ± 16% were included, of which 18 (32%) patients reached the primary endpoint of VA. Patients with recurrent VA in exhibited greater scar mass, core mass, BZ mass, and presence of BZ channels compared with patients without recurrent VA. The presence of BZ channels identified patients with recurrent VA with 67% sensitivity and 85% specificity (area under the ROC curve (AUC) 0.76; 95% CI: 0.63-0.89; p < .001) and was the strongest predictor of the primary endpoint. CONCLUSIONS: The presence of BZ channels was the strongest predictor of recurrent VA in patients with an out of-hospital cardiac arrest and LGE-CMR.


Subject(s)
Cicatrix , Out-of-Hospital Cardiac Arrest , Humans , Cicatrix/diagnostic imaging , Cicatrix/etiology , Contrast Media , Stroke Volume , Out-of-Hospital Cardiac Arrest/diagnosis , Out-of-Hospital Cardiac Arrest/therapy , Ventricular Function, Left , Gadolinium , Arrhythmias, Cardiac , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging, Cine/methods , Predictive Value of Tests
2.
J Cardiovasc Electrophysiol ; 33(2): 254-261, 2022 02.
Article in English | MEDLINE | ID: mdl-34918422

ABSTRACT

BACKGROUND: International guidelines recommend work-up of relatives to autopsy negative sudden cardiac death victims, denoted as sudden unexplained death (SUD) and nonautopsied possible sudden cardiac death (pSCD) victims. This study assesses and compare baseline characteristics and clinical outcome at initial evaluation and during follow-up of relatives to SUD and pSCD victims. METHODS: We retrospectively included data from systematic screening and routine follow-up of first-degree relatives to SUD and pSCD victims referred to our Unit for Inherited Cardiac Diseases, Copenhagen, 2005-2018. Victims with an antemortem known inherited cardiac disease were excluded. RESULTS: We included 371 first-degree relatives from 187 families (120 SUD, 67 pSCD): 276 SUD relatives (age 33 ± 18 years, 54% men) and 95 pSCD relatives (age 40 ± 15 years, 51% men). The diagnostic yields of inherited cardiac diseases in SUD and pSCD families were 16% and 13%, respectively (p = .8). The diagnoses in SUD families were mainly channelopathies (68%), whereas pSCD families were equally diagnosed with cardiomyopathies, channelopathies, and premature ischemic heart disease. Ninety-three percent of diagnosed families were diagnosed at initial evaluation and 7% during follow-up (5.4 ± 3.3 years). During follow-up 34% of relatives with a diagnosed inherited cardiac disease had an arrhythmic event, compared to 5% of relatives without established diagnosis (p < .0001). CONCLUSIONS: Channelopathies dominated in SUD families whereas a broader spectrum of inherited diseases was diagnosed in pSCD families. Most affected relatives were diagnosed at initial evaluation. The event rate was low in relatives without an established diagnosis. Long-term clinical follow-up may not be warranted in all relatives with normal baseline-findings.


Subject(s)
Channelopathies , Heart Diseases , Adolescent , Adult , Autopsy , Channelopathies/diagnosis , Channelopathies/genetics , Death, Sudden, Cardiac/epidemiology , Female , Genetic Testing , Heart Diseases/diagnosis , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
3.
Ann Neurol ; 90(6): 983-987, 2021 12.
Article in English | MEDLINE | ID: mdl-34564866

ABSTRACT

Younger adults with epilepsy have an increased mortality. Some deaths are seizure-related, for example, sudden unexpected death in epilepsy (SUDEP), whereas others, for example, suicide, have multiple causes, including adverse effects of the treatment on mood. In this retrospective population-based study of all Danish persons with epilepsy aged 18 to 49 years during 2007 to 2009 we evaluated the risk of death from seizures and suicide. SUDEP comprised 82.7% of all seizure-related death. Younger adults with epilepsy had an 8.3-fold increased risk of death from seizure-related causes compared with suicide. This underpins the importance of effective seizure control in preventing premature death. ANN NEUROL 2021;90:983-987.


Subject(s)
Epilepsy/mortality , Seizures/mortality , Sudden Unexpected Death in Epilepsy , Suicide/statistics & numerical data , Adolescent , Adult , Cause of Death , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Young Adult
4.
Anesth Analg ; 135(1): 100-109, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35213523

ABSTRACT

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is associated with several cardiovascular complications and higher mortality. Several pathophysiological processes such as hypoxia can trigger POAF, but these are sparsely elucidated, and POAF is often asymptomatic. In patients undergoing major gastrointestinal cancer surgery, we aimed to describe the frequency of POAF as automatically estimated and detected via wireless repeated sampling monitoring and secondarily to describe the association between preceding vital sign deviations and POAF. METHOD: Patients ≥60 years of age undergoing major gastrointestinal cancer surgery were continuously monitored for up to 4 days postoperatively. Electrocardiograms were obtained every minute throughout the monitoring period. Clinical staff were blinded to all measurements. As for the primary outcome, POAF was defined as 30 consecutive minutes or more detected by a purpose-built computerized algorithm and validated by cardiologists. The primary exposure variable was any episode of peripheral oxygen saturation (Spo2) <85% for >5 consecutive minutes before POAF. RESULTS: A total of 30,145 hours of monitoring was performed in 398 patients, with a median of 92 hours per patient (interquartile range [IQR], 54-96). POAF was detected in 26 patients (6.5%; 95% confidence interval [CI], 4.5-9.4) compared with 14 (3.5%; 95% CI, 1.94-5.83) discovered by clinical staff in the monitoring period. POAF was followed by 9.4 days hospitalization (IQR, 6.5-16) versus 6.5 days (IQR, 2.5-11) in patients without POAF. Preceding episodes of Spo2 <85% for >5 minutes (OR, 1.02; 95% CI, 0.24-4.00; P = .98) or other vital sign deviations were not significantly associated with POAF. CONCLUSIONS: New-onset POAF occurred in 6.5% (95% CI, 4.5-9.4) of patients after major gastrointestinal cancer surgery, and 1 in 3 cases was not detected by the clinical staff (35%; 95% CI, 17-56). POAF was not preceded by vital sign deviations.


Subject(s)
Atrial Fibrillation , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Atrial Fibrillation/etiology , Electrocardiography , Humans , Postoperative Complications/diagnosis , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Prospective Studies , Risk Factors
5.
Epilepsia ; 62(10): 2405-2415, 2021 10.
Article in English | MEDLINE | ID: mdl-34418071

ABSTRACT

OBJECTIVE: Persons with epilepsy have an increased mortality including a high risk of sudden unexplained death (SUD), also referred to as sudden unexpected death in epilepsy (SUDEP). We aimed to evaluate the risk of SUDEP in comparison to other causes of death and the risk of SUD in persons with and without epilepsy. METHODS: We undertook a retrospective population-based cohort study of all Danish citizens with and without epilepsy aged 1-49 years during 2007-2009. All deaths in the population were evaluated, and all cases of SUD identified. Primary causes of death in persons with epilepsy were evaluated independently by three neurologists and one neuropediatrician, using the unified SUDEP criteria. RESULTS: The three most frequent causes of death in persons with epilepsy were cancer (2.38 per 1000 person-years), SUDEP (1.65 per 1000 person-years), and pneumonia (1.09 per 1000 person-years) compared with cancer (.17 per 1000 person-years), accident-related deaths (.14 per 1000 person-years), and cardiovascular disease (.09 per 1000 person-years) in persons without epilepsy. Considering definite, definite plus, and probable cases, the SUDEP incidence was .27 per 1000 person-years (95% confidence interval [CI] = .11-.64) in children aged 1-17 years and 1.21 per 1000 person-years (95% CI = .96-1.51) in adults aged 18-49 years. Adjusted for age and sex, persons with epilepsy younger than 50 years had a 10.8-fold (95% CI = 9.97-11.64, p < .0001) increased all-cause mortality and a 34.4-fold (95% CI = 23.57-50.28, p < .0001) increased risk of SUD compared with persons without epilepsy. SUDEP accounted for 23.3% of all SUD. SIGNIFICANCE: This nationwide study of all deaths in persons with epilepsy younger than 50 years found a lower SUDEP risk in children compared with adults, and that epilepsy was a major risk factor for SUD in the background population. This underlines the importance of addressing risk factors for SUDEP to prevent premature death.


Subject(s)
Epilepsy , Sudden Unexpected Death in Epilepsy , Adult , Child , Cohort Studies , Death, Sudden/epidemiology , Death, Sudden/etiology , Denmark/epidemiology , Epilepsy/complications , Humans , Retrospective Studies , Risk Factors
6.
Geophys Res Lett ; 48(24): e2021GL095908, 2021 Dec 28.
Article in English | MEDLINE | ID: mdl-35860449

ABSTRACT

Hypoxia has occurred intermittently in the Baltic Sea since the establishment of brackish-water conditions at ∼8,000 years B.P., principally as recurrent hypoxic events during the Holocene Thermal Maximum (HTM) and the Medieval Climate Anomaly (MCA). Sedimentary phosphorus release has been implicated as a key driver of these events, but previous paleoenvironmental reconstructions have lacked the sampling resolution to investigate feedbacks in past iron-phosphorus cycling on short timescales. Here we employ Laser Ablation (LA)-ICP-MS scanning of sediment cores to generate ultra-high resolution geochemical records of past hypoxic events. We show that in-phase multidecadal oscillations in hypoxia intensity and iron-phosphorus cycling occurred throughout these events. Using a box model, we demonstrate that such oscillations were likely driven by instabilities in the dynamics of iron-phosphorus cycling under preindustrial phosphorus loads, and modulated by external climate forcing. Oscillatory behavior could complicate the recovery from hypoxia during future trajectories of external loading reductions.

7.
PLoS Pathog ; 14(3): e1006936, 2018 03.
Article in English | MEDLINE | ID: mdl-29499056

ABSTRACT

Gut immunity is regulated by intricate and dynamic mechanisms to ensure homeostasis despite a constantly changing microbial environment. Several regulatory factors have been described to participate in feedback responses to prevent aberrant immune activity. Little is, however, known about how transcriptional programs are directly tuned to efficiently adapt host gut tissues to the current microbiome. Here we show that the POU/Oct gene nubbin (nub) encodes two transcription factor isoforms, Nub-PB and Nub-PD, which antagonistically regulate immune gene expression in Drosophila. Global transcriptional profiling of adult flies overexpressing Nub-PB in immunocompetent tissues revealed that this form is a strong transcriptional activator of a large set of immune genes. Further genetic analyses showed that Nub-PB is sufficient to drive expression both independently and in conjunction with nuclear factor kappa B (NF-κB), JNK and JAK/STAT pathways. Similar overexpression of Nub-PD did, conversely, repress expression of the same targets. Strikingly, isoform co-overexpression normalized immune gene transcription, suggesting antagonistic activities. RNAi-mediated knockdown of individual nub transcripts in enterocytes confirmed antagonistic regulation by the two isoforms and that both are necessary for normal immune gene transcription in the midgut. Furthermore, enterocyte-specific Nub-PB expression levels had a strong impact on gut bacterial load as well as host lifespan. Overexpression of Nub-PB enhanced bacterial clearance of ingested Erwinia carotovora carotovora 15. Nevertheless, flies quickly succumbed to the infection, suggesting a deleterious immune response. In line with this, prolonged overexpression promoted a proinflammatory signature in the gut with induction of JNK and JAK/STAT pathways, increased apoptosis and stem cell proliferation. These findings highlight a novel regulatory mechanism of host-microbe interactions mediated by antagonistic transcription factor isoforms.


Subject(s)
Drosophila Proteins/metabolism , Drosophila melanogaster/immunology , Homeodomain Proteins/metabolism , Homeostasis , Immunity, Innate/immunology , Intestines/immunology , POU Domain Factors/metabolism , Animals , Animals, Genetically Modified , Body Patterning , Drosophila Proteins/genetics , Drosophila melanogaster/metabolism , Drosophila melanogaster/microbiology , Female , Gene Expression Regulation, Developmental , Homeodomain Proteins/genetics , Intestines/microbiology , Male , NF-kappa B/genetics , NF-kappa B/metabolism , POU Domain Factors/genetics , Pectobacterium carotovorum/pathogenicity , Protein Isoforms
8.
J Cardiovasc Electrophysiol ; 31(10): 2677-2686, 2020 10.
Article in English | MEDLINE | ID: mdl-33462911

ABSTRACT

AIMS: The current knowledge of idiopathic ventricular fibrillation (IVF) is limited. We aimed to investigate the nature of IVF, including clinical assessment and later diagnosis, and risk factors of implantable cardioverter defibrillator (ICD) therapy in the follow-up period. METHODS: Between 2007 and 2019 we systematically identified all patients from Rigshospitalet, Denmark, with a resuscitated sudden cardiac arrest (SCA) with no identifiable cause. All patients were followed routinely in the ICD outpatient clinic and the majority also in an inherited heart disease outpatient clinic. Outcomes were analysed with Cox regressions models and cumulative incidence curves. RESULTS: We identified 84 patients with an initial diagnosis of IVF; of these, three (3.6%) patients were later diagnosed with a cardiac disease. The remaining IVF patients (n = 81, median age 45 years; men 71.6%) were followed a median follow-up of 5.2 years (interquartile range, 2.0-7.6). A total of 24 (29.6%) patients had appropriate ICD therapy and 12 (14.8%) patients had inappropriate ICD therapy. No predominant type of ventricular arrhythmia at first appropriate ICD therapy was observed. Early repolarization at baseline was not associated with an increased risk of appropriate ICD therapy (P = .842). Repeated cardiac arrest at index SCA increased the risk of appropriate ICD therapy (hazard ratio, 2.63 [95% CI, 1.08-6.40; P = .033]). CONCLUSION: Most patients remained idiopathic throughout the follow-up period and the overall long-term prognosis of IVF was good. Repeated cardiac arrest at index SCA was a risk factor of appropriate ICD therapy and early repolarization was not associated with an increased risk of appropriate ICD therapy.


Subject(s)
Defibrillators, Implantable , Tachycardia, Ventricular , Death, Sudden, Cardiac/epidemiology , Death, Sudden, Cardiac/prevention & control , Electrocardiography , Follow-Up Studies , Humans , Male , Middle Aged , Risk Factors , Ventricular Fibrillation/diagnosis , Ventricular Fibrillation/epidemiology , Ventricular Fibrillation/therapy
9.
Glob Chang Biol ; 26(4): 2235-2250, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31986234

ABSTRACT

Nutrient loading and climate change affect coastal ecosystems worldwide. Unravelling the combined effects of these pressures on benthic macrofauna is essential for understanding the future functioning of coastal ecosystems, as it is an important component linking the benthic and pelagic realms. In this study, we extended an existing model of benthic macrofauna coupled with a physical-biogeochemical model of the Baltic Sea to study the combined effects of changing nutrient loads and climate on biomass and metabolism of benthic macrofauna historically and in scenarios for the future. Based on a statistical comparison with a large validation dataset of measured biomasses, the model showed good or reasonable performance across the different basins and depth strata in the model area. In scenarios with decreasing nutrient loads according to the Baltic Sea Action Plan but also with continued recent loads (mean loads 2012-2014), overall macrofaunal biomass and carbon processing were projected to decrease significantly by the end of the century despite improved oxygen conditions at the seafloor. Climate change led to intensified pelagic recycling of primary production and reduced export of particulate organic carbon to the seafloor with negative effects on macrofaunal biomass. In the high nutrient load scenario, representing the highest recorded historical loads, climate change counteracted the effects of increased productivity leading to a hyperbolic response: biomass and carbon processing increased up to mid-21st century but then decreased, giving almost no net change by the end of the 21st century compared to present. The study shows that benthic responses to environmental change are nonlinear and partly decoupled from pelagic responses and indicates that benthic-pelagic coupling might be weaker in a warmer and less eutrophic sea.

10.
Environ Manage ; 66(6): 1024-1038, 2020 12.
Article in English | MEDLINE | ID: mdl-32910293

ABSTRACT

Decision-support tools (DSTs) synthesize complex information to assist environmental managers in the decision-making process. Here, we review DSTs applied in the Baltic Sea area, to investigate how well the ecosystem approach is reflected in them, how different environmental problems are covered, and how well the tools meet the needs of the end users. The DSTs were evaluated based on (i) a set of performance criteria, (ii) information on end user preferences, (iii) how end users had been involved in tool development, and (iv) what experiences developers/hosts had on the use of the tools. We found that DSTs frequently addressed management needs related to eutrophication, biodiversity loss, or contaminant pollution. The majority of the DSTs addressed human activities, their pressures, or environmental status changes, but they seldom provided solutions for a complete ecosystem approach. In general, the DSTs were scientifically documented and transparent, but confidence in the outputs was poorly communicated. End user preferences were, apart from the shortcomings in communicating uncertainty, well accounted for in the DSTs. Although end users were commonly consulted during the DST development phase, they were not usually part of the development team. Answers from developers/hosts indicate that DSTs are not applied to their full potential. Deeper involvement of end users in the development phase could potentially increase the value and impact of DSTs. As a way forward, we propose streamlining the outputs of specific DSTs, so that they can be combined to a holistic insight of the consequences of management actions and serve the ecosystem approach in a better manner.


Subject(s)
Ecosystem , Eutrophication , Biodiversity , Environmental Pollution , Humans , Uncertainty
11.
Zhongguo Zhong Yao Za Zhi ; 45(22): 5537-5554, 2020 Nov.
Article in Zh | MEDLINE | ID: mdl-33350217

ABSTRACT

In this study, the chemical profiling of Jingyin Granules and the tissue distribution of nine major constituents in this Chinese medicine were performed after oral administration of Jingyin Granules to rats, by using UHPLC-Q-Exactive Orbitrap HR-MS. An Acquity UPLC BEH C_(18) chromatographic column(2.1 mm×100 mm, 1.7 µm) was used as solid phase, while the mobile phase was methanol and 0.1% formic acid water for gradient elution. The major constituents in this Chinese medicine were quickly and accurately identified, via comparison with the retention times and MS/MS spectra of the standards. A total of 106 chemicals were identified from Jingyin Granules, including 24 kinds of organic acids, 47 kinds of flavonoids, 10 kinds of iridoids, and 21 kinds of saponins and 4 kinds of other compounds. After oral administered Jingyin Granules to rats, 48, 30, 25, 23, 45, 34, 39, 26, 19 prototype compounds were identified in serum, heart, liver, spleen, lung, kidney, brain, fat, and testicles, respectively. Meanwhile, an LC-MS based analytical method was established for simultaneous determination of chlorogenic acid, swertiamarin, caffeic acid, sweroside, liquiritin, prim-O-glucosylcimifugin, arctiin, 5-O-methylvisammioside and arctigenin in biological samples. The tissue distribution(serum, liver and lung) of these nine aim constituents in rats after oral administration of Jingyin Granules were investigated. It was found that these nine constituents could be quickly absorbed into circulation system and then distributed to liver and lung tissues. Except arctigenin, the exposure of other eight aim constituents to serum and lung was peaked at 1 h. At 1 h, the exposure of these components to lung tissue were ranked as follows: swertiamarin [(75 191.0±3 483.21) ng·g~(-1)]>arctiin [(2 716.5±36.06) ng·g~(-1)]>5-O-methylvisammioside [(585.1±0.71) ng·g~(-1)]>arctigenin [(437.45±3.18) ng·g~(-1)]>chlorogenic acid [(308.1±5.66) ng·g~(-1)]>prim-O-glucosylcimifugin [(211.35±2.19) ng·g~(-1)]>sweroside [(184.3±9.05) ng·g~(-1)]>caffeic acid [(175.95±2.05) ng·g~(-1)]>liquiritin [(174.78±153.34) ng·g~(-1)]. In summary, an UHPLC-Q-Exactive Orbitrap HR-MS method has been established for rapid and accurate identification of the constituents in Jingyin Granules, while the tissue distribution of nine major absorpted constituents were investigated in rats following oral administration of Jingyin Granules. These findings provided key information and guidance for further studies on pharmacodynamic substances and clinical applications of Jingyin Granules.


Subject(s)
Drugs, Chinese Herbal , Tandem Mass Spectrometry , Animals , Chromatography, High Pressure Liquid , Chromatography, Liquid , Rats , Tissue Distribution
12.
Zhongguo Zhong Yao Za Zhi ; 45(19): 4719-4724, 2020 Oct.
Article in Zh | MEDLINE | ID: mdl-33164438

ABSTRACT

To investigate the effect of salidroside on the proteomics of erythrocyte membrane in high altitude erythrocytosis(HAPC) rats, in order to explore the mechanism of salidroside in improving HAPC based on the proteomics analysis. First, HPAC rat models were established, and 16 rats were randomly divided into HAPC model group and salidroside(100 mg·kg~(-1)) treatment group(8 rats per group). Saline was administered to the HAPC model group, while salidroside treatment group was given 100 mg·kg~(-1) salidroside once a day. After continuous oral administration with salidroside for 40 days(once a day), blood was collected from the femoral artery to obtain total red blood cell membrane proteins. Two-dimensional electrophoresis was used to separate total proteins. The two-dimensional electrophoresis of erythrocyte membrane proteins was analyzed before and after salidroside intervention, and the proteins with significant differences were identified by mass spectrometry. Finally, biological functions were analyzed using bioinformatics. A two-dimensional electrophoresis method was used to establish a protein expression profile with a high resolution and reproducibility of erythrocyte membranes in HAPC rats. Salidroside treatment significantly changed 18 protein spots in the 2-DE map of erythrocyte membranes, of which 13 proteins were up-regulated and 5 proteins were down-regulated. Eight differential proteins were successfully identified by mass spectrometry. Moreover, bioinformatics analysis found that these differential proteins were involved in such biological processes as oxidative stress, redox, and peroxisome pathway, which are mainly associated with peroxisome and MAPK signaling pathways. Therefore, salidroside could significantly change the expressions of erythrocyte membrane proteins in HAPC rats. Eight differential proteins were identified by a proteomic-based approach. The differential proteins were involved in such biological processes as oxidative stress, redox, peroxisome pathway.


Subject(s)
Polycythemia , Altitude , Animals , Erythrocytes , Glucosides , Phenols , Proteomics , Rats , Reproducibility of Results
13.
Reprod Fertil Dev ; 30(11): 1541-1552, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29778102

ABSTRACT

The aim of the present study was to investigate the effects of a strategy for extending pro-oestrus (the interval between luteolysis and ovulation) in an oestrus synchronisation protocol (named J-Synch) in beef heifers on follicular growth, sexual steroid concentrations, the oestrogen receptor ERα and progesterone receptors (PR) in the uterus, insulin-like growth factor (IGF) 1 and pregnancy rates. In Experiment 1, heifers treated with the new J-Synch protocol had a longer pro-oestrus period than those treated with the conventional protocol (mean (±s.e.m.) 93.7±12.9 vs 65.0±13.7h respectively; P<0.05). The rate of dominant follicle growth from the time of progesterone device removal to ovulation was greater in heifers in the J-Synch than conventional group (P<0.05). Luteal area and serum progesterone concentrations were greater in the J-Synch Group (P<0.05) for the 12 days after ovulation. Progesterone receptor (PGR) staining on Day 6 after ovulation in the uterine stroma was lower in the J-Synch than conventional group (P<0.05), and the expression of PR gene (PGR) and IGF1 gene tended to be lower in J-Synch-treated heifers (P<0.1). In Experiment 2 (n=2349), the pregnancy rate 30-35 days after fixed-time AI (FTAI) was greater for heifers in the J-Synch than conventional group (56.1% vs 50.7% respectively). In conclusion, our strategy for extending pro-oestrus (i.e. the J-Synch protocol) significantly improves pregnancy establishment in beef heifers. This improvement was related to an increased rate of growth of the dominant ovulatory follicle, greater progesterone concentrations during the ensuing luteal phase and different uterine patterns of PGR and IGF1, which may have favoured embryo development and pregnancy establishment.


Subject(s)
Estradiol/analogs & derivatives , Estrus Synchronization/physiology , Ovary/physiology , Proestrus/physiology , Progesterone/administration & dosage , Uterus/physiology , Animals , Cattle , Estradiol/administration & dosage , Estradiol/blood , Estrus Synchronization/drug effects , Female , Ovarian Follicle/diagnostic imaging , Ovarian Follicle/drug effects , Ovary/diagnostic imaging , Ovary/drug effects , Pregnancy , Proestrus/drug effects , Progesterone/blood , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Uterus/diagnostic imaging , Uterus/drug effects
14.
Proc Natl Acad Sci U S A ; 111(15): 5628-33, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24706804

ABSTRACT

Deoxygenation is a global problem in coastal and open regions of the ocean, and has led to expanding areas of oxygen minimum zones and coastal hypoxia. The recent expansion of hypoxia in coastal ecosystems has been primarily attributed to global warming and enhanced nutrient input from land and atmosphere. The largest anthropogenically induced hypoxic area in the world is the Baltic Sea, where the relative importance of physical forcing versus eutrophication is still debated. We have analyzed water column oxygen and salinity profiles to reconstruct oxygen and stratification conditions over the last 115 y and compare the influence of both climate and anthropogenic forcing on hypoxia. We report a 10-fold increase of hypoxia in the Baltic Sea and show that this is primarily linked to increased inputs of nutrients from land, although increased respiration from higher temperatures during the last two decades has contributed to worsening oxygen conditions. Although shifts in climate and physical circulation are important factors modulating the extent of hypoxia, further nutrient reductions in the Baltic Sea will be necessary to reduce the ecosystems impacts of deoxygenation.


Subject(s)
Climate Change , Ecosystem , Oxygen/analysis , Seawater/chemistry , Water Pollution/analysis , Anaerobiosis , Baltic States , Linear Models , Oceans and Seas , Salinity , Species Specificity , Temperature , Time Factors , Water Movements , Water Pollution/prevention & control
15.
Environ Sci Technol ; 50(21): 11787-11796, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27704806

ABSTRACT

Eutrophication is expanding worldwide, but its implication for production and bioaccumulation of neurotoxic monomethylmercury (MeHg) is unknown. We developed a mercury (Hg) biogeochemical model for the Baltic Sea and used it to investigate the impact of eutrophication on phytoplankton MeHg concentrations. For model evaluation, we measured total methylated Hg (MeHgT) in the Baltic Sea and found low concentrations (39 ± 16 fM) above the halocline and high concentrations in anoxic waters (1249 ± 369 fM). To close the Baltic Sea MeHgT budget, we inferred an average normoxic water column HgII methylation rate constant of 2 × 10-4 d-1. We used the model to compare Baltic Sea's present-day (2005-2014) eutrophic state to an oligo/mesotrophic scenario. Eutrophication increases primary production and export of organic matter and associated Hg to the sediment effectively removing Hg from the active biogeochemical cycle; this results in a 27% lower present-day water column Hg reservoir. However, increase in organic matter production and remineralization stimulates microbial Hg methylation resulting in a seasonal increase in both water and phytoplankton MeHg reservoirs above the halocline. Previous studies of systems dominated by external MeHg sources or benthic production found eutrophication to decrease MeHg levels in plankton. This Baltic Sea study shows that in systems with MeHg production in the normoxic water column eutrophication can increase phytoplankton MeHg content.


Subject(s)
Phytoplankton , Water Pollutants, Chemical , Environmental Monitoring , Eutrophication , Mercury , Methylmercury Compounds
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