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1.
Sci Adv ; 6(9): eaaz3801, 2020 02.
Article in English | MEDLINE | ID: mdl-32133409

ABSTRACT

Illegal, unreported, and unregulated fishing is widespread; it is therefore likely that illicit trade in marine fish catch is also common worldwide. We combine ecological-economic databases to estimate the magnitude of illicit trade in marine fish catch and its impacts on people. Globally, between 8 and 14 million metric tons of unreported catches are potentially traded illicitly yearly, suggesting gross revenues of US$9 to US$17 billion associated with these catches. Estimated loss in annual economic impact due to the diversion of fish from the legitimate trade system is US$26 to US$50 billion, while losses to countries' tax revenues are between US$2 and US$4 billion. Country-by-country estimates of these losses are provided in the Supplementary Materials. We find substantial likely economic effects of illicit trade in marine fish catch, suggesting that bold policies and actions by both public and private actors are needed to curb this illicit trade.


Subject(s)
Conservation of Natural Resources/economics , Ecosystem , Fisheries/economics , Fishes , Models, Biological , Models, Economic , Animals , Humans
2.
J Chem Phys ; 149(23): 234908, 2018 Dec 21.
Article in English | MEDLINE | ID: mdl-30579322

ABSTRACT

This work addresses the use of the Gaussian approximation as a common tool to extract atomic motions in proteins from elastic incoherent neutron scattering and whether improvements in data analysis and additional information can be obtained when going beyond that. We measured alpha-lactalbumin with different levels of hydration on three neutron backscattering spectrometers, to be able to resolve a wide temporal and spatial range for dynamics. We demonstrate that the Gaussian approximation gives qualitatively similar results to models that include heterogeneity, if one respects a certain procedure to treat the intercept of the elastic intensities with the momentum transfer axis. However, the inclusion of motional heterogeneity provides better fits to the data. Our analysis suggests an approach of limited heterogeneity, where including only two kinds of motions appears sufficient to obtain more quantitative results for the mean square displacement. Finally, we note that traditional backscattering spectrometers pose a limit on the lowest accessible momentum transfer. We therefore suggest that complementary information about the spatial evolution of the elastic intensity close to zero momentum transfer can be obtained using other neutron methods, in particular, neutron spin-echo together with polarization analysis.

3.
Phys Chem Chem Phys ; 19(37): 25369-25379, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28894859

ABSTRACT

An essential role of enzymes is to catalyze various chemical reactions in the human body and inhibition of the enzymatic activity by small molecules is the mechanism of action of many drugs or tool compounds used to study biological processes. Here, we investigate the effect on the dynamics of the serine protease α-chymotrypsin when in complex with two different covalently bound inhibitors using elastic incoherent neutron scattering. The results show that the inhibited enzyme displays enhanced dynamics compared to the free form. The difference was prominent at higher temperatures (240-310 K) and the type of motions that differ include both small amplitude motions, such as hydrogen atom rotations around a methyl group, and large amplitude motions, such as amino acid side chain movements. The measurements were analyzed with multivariate methods in addition to the standard univariate methods, allowing for a more in-depth analysis of the types of motions that differ between the two forms. The binding strength of an inhibitor is linked to the changes in dynamics occurring during the inhibitor-enzyme binding event and thus these results may aid in the deconvolution of this fundamental event and in the design of new inhibitors.


Subject(s)
Chymotrypsin/metabolism , Neutron Diffraction , Protein Binding , Amino Acids/chemistry , Biophysical Phenomena , Catalysis , Elasticity , Humans , Hydrogen , Molecular Dynamics Simulation , Motion
4.
Neuroscience ; 283: 222-30, 2014 Dec 26.
Article in English | MEDLINE | ID: mdl-24881573

ABSTRACT

Multiple sclerosis (MS) is a chronic neurological disease characterized by inflammation and degeneration within the CNS. Over the course of the disease, most MS patients successively accumulate inflammatory lesions, axonal damage, and a rather diffuse CNS pathology, along with an increasing degree of disability. Pharmacological treatment options which are currently approved for MS aim at limiting inflammation and decreasing the relapse rate, or at simply relieving symptoms. Established disease-modifying and immunosuppressive treatments are unable to prevent the accumulation of pathology in most patients over long-term. Therefore, therapies promoting the innate ability of the CNS to compensate for dysfunction resulting from brain injury might be highly beneficial in MS. As a precondition, however, development of such strategies requires well-grounded knowledge about the extent to which central plasticity is intact and accessible in MS patients, and whether it is functionally relevant at all. This review will focus on plasticity of the motor system in patients with MS. A number of functional imaging studies have assessed patterns of brain activation during simple motor tasks in MS patients and their relationship with CNS damage and motor function. Deeper insights about causal and functional relationships were gained by neurophysiological techniques, predominantly by transcranial magnetic stimulation. In addition, and probably closest to rehabilitative approaches, practice-induced plasticity has been probed in a few studies. Altogether, there is growing evidence for a preservation of rapid-onset motor plasticity and for functionally relevant chronic reorganization processes, which might be limited by high CNS injury in advanced stages of the disease. Clinical implications of these findings with regard to the development and optimization of rehabilitative treatments in MS are discussed, as well as open questions which need to be addressed by future studies.


Subject(s)
Brain/pathology , Multiple Sclerosis , Neuronal Plasticity/physiology , Recovery of Function/physiology , Animals , Humans , Multiple Sclerosis/pathology , Multiple Sclerosis/physiopathology , Multiple Sclerosis/therapy , Neuroimaging
6.
Schmerz ; 26(1): 8-15, 2012 Feb.
Article in German | MEDLINE | ID: mdl-22134376

ABSTRACT

Pain-related evoked potentials (PREPs) represent a novel method for the evaluation of peripheral and central nociceptive pathways, e.g. in the diagnosis of small fiber neuropathy (SFN) or after therapeutic interventions for headache. Compared to contact heat-evoked and laser-evoked potentials, recording of PREPs is less stressful for the subjects and technically less demanding. The clinical usefulness of PREPs has been described for SFN associated with diabetes, HIV and hepatitis C infections as well as in headache and facial pain disorders. They have also been evaluated after interventional methods, such as direct current stimulation (tDCS). The article reviews and discusses the advantages and pitfalls of this technique in the context of recent clinical studies as compared to other paradigms of peripheral electrical stimulation and delineates perspectives and possible indications.


Subject(s)
Evoked Potentials, Somatosensory/drug effects , Evoked Potentials, Somatosensory/physiology , Nociceptors/drug effects , Nociceptors/physiology , Pain/drug therapy , Pain/physiopathology , Adult , Analgesics/adverse effects , Analgesics/therapeutic use , Electric Stimulation , Female , Headache/drug therapy , Headache/physiopathology , Humans , Lasers , Male , Nerve Fibers, Myelinated/drug effects , Nerve Fibers, Myelinated/physiology , Pain Measurement/drug effects , Pain Measurement/methods , Pain Threshold/drug effects , Pain Threshold/physiology , Peripheral Nerves/drug effects , Peripheral Nerves/physiopathology , Peripheral Nervous System Diseases/diagnosis , Peripheral Nervous System Diseases/physiopathology , Predictive Value of Tests , Reaction Time/drug effects , Reaction Time/physiology , Skin/innervation , Thermosensing/drug effects , Thermosensing/physiology , Treatment Outcome
7.
Neurology ; 78(2): 122-8, 2012 Jan 10.
Article in English | MEDLINE | ID: mdl-22205757

ABSTRACT

OBJECTIVE: To examine whether the corticospinal system emanating from the primary motor cortex may be organized to facilitate generation of dystonic movements. METHODS: In this cross-sectional observational study, finger movement (FM) representations were assessed in 10 patients with focal hand dystonia (FHD) and 10 matched healthy controls by transcranial magnetic stimulation during rest. Evoked finger movements of the right hand were recorded using an instrumented data glove. Patterns of finger joint movements were analyzed using cluster analysis. Principal component analysis and centers of gravity for finger movement representations and motor evoked potentials recorded from the abductor pollicis brevis and abductor digiti minimi muscles were computed. For comparison, high-resolution somatosensory evoked potentials (SSEP) were recorded after electrical stimulation of the thumb (D1) or little finger (D5) in the same patients. Source reconstruction for the N20 SSEP component was performed using a dual-dipole model. RESULTS: Stimulation of the resting motor cortex did not reveal overt abnormalities in FHD, neither with respect to finger joint movement patterns nor with respect to the topologic organization of finger movements or intrinsic hand muscle representations. However, in line with previous reports, the distance between the dipole sources of D1 and D5 in the somatosensory cortex (S1) was smaller in patients with FHD, suggesting disruption of homuncular finger representations in S1. CONCLUSIONS: Our findings may imply that abnormality of motor organization in focal hand dystonia arises principally only during activation, when abnormal somatosensory representations are functionally integrated.


Subject(s)
Dystonic Disorders/pathology , Dystonic Disorders/physiopathology , Evoked Potentials, Motor/physiology , Hand , Motor Cortex/physiopathology , Adult , Aged , Brain Mapping , Cross-Sectional Studies , Electric Stimulation , Electromyography , Evoked Potentials, Somatosensory/physiology , Female , Hand/innervation , Humans , Male , Middle Aged , Movement/physiology , Principal Component Analysis , Psychomotor Performance , Pyramidal Tracts/physiopathology , Transcranial Magnetic Stimulation
8.
Neurology ; 74(9): 728-35, 2010 Mar 02.
Article in English | MEDLINE | ID: mdl-20194911

ABSTRACT

OBJECTIVE: To study rapid-onset central motor plasticity, and its relationship to motor impairment and CNS injury in patients with multiple sclerosis (MS). METHODS: In this cross-sectional observational study, motor plasticity was examined neurophysiologically and behaviorally in 22 patients with moderately severe (median Expanded Disability Status Scale score 2.5 [0-6]) stable MS and matched healthy controls. First, plasticity was assessed using paired associative stimulation (PAS), a protocol modeling long-term synaptic potentiation in human cortex. PAS combines repetitive electric nerve stimulation with transcranial magnetic stimulation (TMS) of the contralateral motor cortex. Second, motor learning was tested by a force production task. Motor impairment was assessed by functional tests. CNS injury was evaluated by obtaining normalized N-acetyl-aspartate (NAA/Cr) spectra using magnetic resonance spectroscopy and by the corticomuscular latency (CML) to the abductor pollicis brevis muscle as tested by TMS. RESULTS: Patients with MS performed worse than controls in functional motor tests, CMLs were prolonged, and NAA/Cr was decreased. PAS-induced enhancement of corticospinal excitability and training-induced increments of motor performance were comparable between patients with MS and controls. Neither PAS-induced plasticity nor motor learning performance correlated with motor impairment or measures of CNS injury. Patients with high CNS injury and good motor performance did not differ significantly from those with high CNS injury and poor motor performance with respect to PAS-induced plasticity and motor learning success. CONCLUSIONS: Despite motor impairment and CNS injury in patients with multiple sclerosis (MS), rapid-onset motor plasticity is comparable to that in healthy subjects. Compensation of MS-related CNS injury is unlikely to be constrained by insufficient rapid-onset neuroplasticity.


Subject(s)
Motor Activity/physiology , Motor Cortex/physiopathology , Multiple Sclerosis, Chronic Progressive/physiopathology , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Neuronal Plasticity , Pyramidal Tracts/physiopathology , Adult , Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Creatine/metabolism , Cross-Sectional Studies , Female , Humans , Learning/physiology , Male , Middle Aged , Muscle, Skeletal/physiopathology , Time Factors , Young Adult
9.
Fortschr Neurol Psychiatr ; 77 Suppl 1: S45-8, 2009 Aug.
Article in German | MEDLINE | ID: mdl-19685393

ABSTRACT

Multiple Sclerosis (MS) is associated with a chronic demyelinating and axonal injury to the central nervous system. Functional activation studies in MS patients have demonstrated that performance of simple motor tasks may activate non-canonical brain regions. Using virtual lesion induction by transcranial magnetic stimulation, it is possible to show that this activation is functionally relevant. Rapid-onset neuronal plasticity in patients with mild-to-moderate MS is uncompromised despite many plasticity-impeding factors. Long-term adaptive mechanisms, relying on the formation on new neuronal connections, most likely are the principal mechanism underlying compensation of brain injury in MS.


Subject(s)
Efferent Pathways/physiopathology , Multiple Sclerosis/physiopathology , Neuronal Plasticity/physiology , Efferent Pathways/pathology , Humans , Movement/physiology , Multiple Sclerosis/pathology , Neural Pathways/pathology , Transcranial Magnetic Stimulation
10.
Ecotoxicol Environ Saf ; 64(1): 85-99, 2006 May.
Article in English | MEDLINE | ID: mdl-16439022

ABSTRACT

An environmental risk assessment for alcohol ethoxylates (AE) is presented that integrates wastewater treatment plant monitoring, fate, and ecotoxicity research with a new application of mixture toxicity theory based on simple similar concentration addition of AE homologs in a species-sensitivity distribution (SSD) context. AEs are nonionic surfactants composed of a homologous series of molecules that range in alkyl chain length from 12 to 18 carbons and ethoxylates from 0 to 18 units. Chronic ecotoxicity of AE is summarized for 17 species in 60 tests and then normalized to monitoring data for AE mixtures. To do so, chronic aquatic toxicity was first expressed as EC10 per species (the concentration predicted to cause a 10% reduction in an important ecological endpoint). Normalization integrated several new quantitative structure-activity relationships for algae, daphnids, fish, and mesocosms and provided an interpretation of toxicity test data as a function of individual homologs in an AE mixture. SSDs were constructed for each homolog and the HC5 (hazardous concentration protective of 95% of species based on a small biological effect [the chronic EC10]) was predicted. Total mass of AE in monitored effluents from 29 sites in Europe, Canada, and the United States averaged 6.8, 2.8, and 3.55 microg/L, respectively. For risk assessment purposes, correction of exposure to account for fatty alcohol derived from sources other than AE and for sorbed components based on experimental evidence was used to determine AE concentrations in undiluted (100%) effluents from North America and Europe. Exposure and effect findings were integrated in a toxic unit (TU)-based model that considers the measured distribution of individual AE homologs in effluent with their corresponding SSDs. Use of environmentally relevant exposure corrections (bioavailability and accounting for AE-derived alcohol) resulted in TUs ranging from 0.015 to 0.212. Low levels of risk are concluded for AE in the aquatic environments of Europe and North America.


Subject(s)
Alcohols/toxicity , Water Pollutants, Chemical/toxicity , Adsorption , Alcohols/analysis , Algorithms , Animals , Biodegradation, Environmental , Daphnia , Eukaryota , Europe , Fishes , North America , Quantitative Structure-Activity Relationship , Reference Values , Risk Assessment , Species Specificity , Terminology as Topic , Water Microbiology , Water Pollutants, Chemical/analysis
12.
Mo Med ; 98(3): 97-102, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11265143

ABSTRACT

Vertebroplasty is an effective technique in which polymethyl methacrylate, a surgical cement, is injected into a vertebral body. This technique provides increased strength and pain relief in vertebrae weakened by osseous lesions as metastases, multiple myeloma, and aggressive hemangiomas, and from osteoporotic fractures. Infrequent serious complications are mainly related to polymethyl methacrylate leakage into the spinal canal and around vital soft tissue structures. Complications are decreased by careful fluoroscopic guidance and meticulous radiological technique. Indications should be dictated by a multidisciplinary team approach.


Subject(s)
Back Pain/surgery , Minimally Invasive Surgical Procedures/methods , Polymethyl Methacrylate , Spinal Cord Compression/surgery , Contraindications , Humans , Injections, Subcutaneous , Minimally Invasive Surgical Procedures/adverse effects , Missouri , Treatment Outcome
16.
J Clin Microbiol ; 13(5): 885-7, 1981 May.
Article in English | MEDLINE | ID: mdl-7240401

ABSTRACT

Four recent cases of Yersinia enterocolitica infections from Florida are discussed. Two of the cases presented as acute mesenteric lymphadenitis, and the other two presented as septicemia. Three of the isolates were an uncommon serotype, O:2,3, and the fourth was serotype O:5. The increasing occurrence of Y. enterocolitica in semitropical areas of the United States is emphasized.


Subject(s)
Mesenteric Lymphadenitis/etiology , Sepsis/etiology , Yersinia Infections/etiology , Yersinia/classification , Adolescent , Child , Female , Florida , Humans , Infant , Male , Middle Aged , Serotyping
17.
Mayo Clin Proc ; 55(8): 513-5, 1980 Aug.
Article in English | MEDLINE | ID: mdl-7401694

ABSTRACT

Three cases of disseminated cryptococcosis associated with massive levels of cryptococcal antigen in the serum and cerebrospinal fluid are presented. These patients had antigen titers of at least 1:32,768. Titers of this magnitude have not previously been reported.


Subject(s)
Antigens, Fungal/blood , Cryptococcosis/diagnosis , Adult , Aged , Antigens, Fungal/cerebrospinal fluid , Cryptococcosis/immunology , Cryptococcosis/pathology , Female , Humans , Immunosuppressive Agents/adverse effects , Meninges/pathology , Meningitis/diagnosis , Meningitis/immunology , Meningitis/pathology , Thyroid Gland/pathology
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