Abstract
In cold climates, some plants and bacteria that cannot avoid freezing use antifreeze proteins (AFPs) to lessen the destructive effects of ice recrystallization. These AFPs have weak freezing ...point depression activity, perhaps to avoid sudden, uncontrolled growth of ice. Here, we report on an uncharacteristically powerful bacterial AFP found in an Antarctic strain of the bacterium, Marinomonas primoryensis. It is Ca2+-dependent, shows evidence of cooperativity, and can produce over 2 °C of freezing point depression. Unlike most AFPs, it does not produce obvious crystal faceting during thermal hysteresis. This AFP might be capable of imparting freezing avoidance to M. primoryensis in ice-covered Antarctic lakes. A hyperactive bacterial AFP has not previously been reported.
Understanding of the role of turbulence in controlling transport processes is of paramount importance for the preservation and protection of aquatic ecosystems, the minimization of the deleterious ...consequences of anthropogenic activity, and the successful sustainable development of river and maritime areas. In this context, the present Special Issue collects 15 papers which provide a representation of the present understanding of turbulent processes and their effects in river and maritime environments. The presented collection of papers is not exhaustive, but it highlights the key priority areas and knowledge gaps in this field of research.
The published papers present the state-of-the-art knowledge of complex environmental flows which are useful for researchers and practitioners. The paper contents are an overview of some recent topics of research and an exposure of the current and future challenges associated with these topics.
Background: Markers indicative of micronutrient and antioxidant status in children with cerebral palsy (CP) were explored due to these children’s well-documented issues with food intake and the ...limited biochemical literature. Materials and Methods: Children aged 4 to 12 years with marked CP (n = 24) and controls (n = 24) were recruited. The CP group represented orally (O) or enterally fed (E) children. Concentrations of red cell folate (RCF), magnesium, superoxide dismutase (SOD), glutathione reductase, and peroxidase were measured, as well as serum methylmalonic acid and vitamin C. Plasma hemoglobin, C-reactive protein, α-tocopherol, cholesterol, zinc, protein carbonyls, and total antioxidant capacity were also quantified. Results: Data are reported as mean (SD) and z scores where values differ with age. Many similarities existed, but zinc z scores were reduced in O (–1.10 0.83) vs controls (–0.54 0.54) (P < .05), as well as for glutathione reductase in O (10.15 1.69) vs E (12.22 2.41) and controls (11.51 1.67) (P < .05). RCF was greatly increased in E (1422 70) vs O (843 80) and controls (820 43) (P < .001). SOD was decreased in E (24.3 1.4) vs controls (27.0 2.8) (P < .05). Conclusion: Considering their vast impact on physiology, micronutrients should be routinely monitored in orally fed children with swallowing disorders and dietary limitations. Excessive intakes, particularly long term in enterally fed children, should also be monitored in view of their potential for competitive inhibition, particularly at high levels.
The three trials of SS camp personnel, held in Frankfurt am Main in the mid-1960s, represent a key moment in the development of public awareness of and attitudes towards the Holocaust in West and ...East Germany. The involvement of several hundred witnesses, many of whom were survivors, from across the world and collectively speaking 11 different languages, brought home the international scale of the genocide and drew attention to the individual quality of the witnesses’ voices as they told their stories. The only interpreter at the trial who attracted public attention for her work and who left a substantial trace in the archival record was the Polish-Russian-German interpreter Wera Kapkajew, who also accompanied the court on its visit to the Auschwitz complex. In contrast to the other interpreters, her work and biography attracted journalistic interest and she was singled out for praise by court personnel and witnesses: in particular, she is praised for conveying the nuances of the witness’ voices, rather than just the content of their testimony. This article explores Kapkajew’s contribution to the trial proceedings and what happens when an interpreter’s work becomes visible in a Holocaust trial.
In Alzheimer's disease and frontotemporal dementias the microtubule-associated protein tau forms intracellular paired helical filaments (PHFs). The filaments formed in vivo consist mainly of ...full-length molecules of the six different isoforms present in adult brain. The substructure of the PHF core is still elusive. Here we applied scanning transmission electron microscopy (STEM) and limited proteolysis to probe the mass distribution of PHFs and their surface exposure. Tau filaments assembled from the three repeat domain have a mass per length (MPL) of approximately 60 kDa/nm and filaments from full-length tau (htau40DeltaK280 mutant) have approximately 160 kDa/nm, compared with approximately 130 kDa/nm for PHFs from Alzheimer's brain. Polyanionic cofactors such as heparin accelerate assembly but are not incorporated into PHFs. Limited proteolysis combined with N-terminal sequencing and mass spectrometry of fragments reveals a protease-sensitive N-terminal half and semiresistant PHF core starting in the first repeat and reaching to the C-terminus of tau. Continued proteolysis leads to a fragment starting at the end of the first repeat and ending in the fourth repeat. PHFs from tau isoforms with four repeats revealed an additional cleavage site within the middle of the second repeat. Probing the PHFs with antibodies detecting epitopes either over longer stretches in the C-terminal half of tau or in the fourth repeat revealed that they grow in a polar manner. These data describe the physical parameters of the PHFs and enabled us to build a model of the molecular arrangement within the filamentous structures.
Infants who present or are admitted to hospital with illness or with inadequate growth and development are those most at risk of decreased nutritional status. However, not all infants who present or ...are admitted to hospital have their growth assessed. The aim of the present study was to identify how frequently anthropometric measurements were documented in charts of infants presenting and/or admitted to a tertiary paediatric hospital.
A systematic random sample of hospital charts of infants who had presented to the emergency department between 1 July 2011 and 30 June 2012 was audited retrospectively for the presence of appropriate documentation of measurement.
In all, 465 charts were audited, representing 10% of infants who presented to the emergency department in the year. The frequency of anthropometric measures was: birthweight 103 (22%), presentation weight 275 (59%), length 8 (2%), head circumference 15 (3%), percentiles 27 (6%) and body mass index score 1 (0%). Age of the infant was significantly associated with recording of birthweight. There were no significant relationships found between gender, socioeconomic status, gestational age, delivery type and recording of diagnosis and birthweight.
Infant measurements were not recorded on many occasions. Assessment of growth as a marker of illness or nutritional deficit has been poorly assessed in this group. This is a missed opportunity to assess infant growth in this population, which has been found to be at risk of decreased nutritional status. Identification and treatment of growth deficits are a cost-effective method of optimising infant health worldwide.
NPC-1 gene mutations cause Niemann-Pick type C (NPC), a neurodegenerative storage disease resulting in premature death in humans. Spontaneous mutation of the NPC-1 gene in mice generates a similar ...phenotype, usually with death ensuing by 12 weeks of age. Both human and murine NPC are characterized neuropathologically by ballooned neurons distended with lipid storage, axonal spheroid formation, demyelination, and widespread neuronal loss. To elucidate the biochemical mechanism underlying this neuropathology, we have investigated the phosphorylation of neuronal cytoskeletal proteins in the brains of npc-1 mice. A spectrum of antibodies against phosphorylated epitopes in neurofilaments (NFs) and MAP2 and tau were used in immunohistochemical and immunoblotting analyses of 4- to 12-week-old mice. Multiple sites in NFs, MAP2, and tau were hyperphosphorylated as early as 4 weeks of age and correlated with a significant increase in activity of the cyclin-dependent kinase 5 (cdk5) and accumulation of its more potent activator, p25, a proteolytic fragment of p35. At 5 weeks of age, the development of axonal spheroids was noted in the pons. p25 and cdk5 coaccumulated with hyperphosphorylated cytoskeletal proteins in axon spheroids. These various abnormalities escalated with each additional week of age, spreading to other regions of the brainstem, basal ganglia, cerebellum, and eventually, the cortex. Our data suggest that focal deregulation of cdk5/p25 in axons leads to cytoskeletal abnormalities and eventual neurodegeneration in NPC. The npc-1 mouse is a valuable in vivo model for determining how and when cdk5 becomes deregulated and whether cdk5 inhibitors would be useful in blocking NPC neurodegeneration.
Neurofibrillary tangles (NFT) composed of the microtubule-associated protein tau are prominent in Alzheimer disease (AD), Pick disease, progressive supranuclear palsy (PSP) and corticobasal ...degeneration (CBD). Mutations in the gene (Mtapt) encoding tau protein cause frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), thereby proving that tau dysfunction can directly result in neurodegeneration. Expression of human tau containing the most common FTDP-17 mutation (P301L) results in motor and behavioural deficits in transgenic mice, with age- and gene-dose-dependent development of NFT. This phenotype occurred as early as 6.5 months in hemizygous and 4.5 months in homozygous animals. NFT and Pick-body-like neuronal lesions occurred in the amygdala, septal nuclei, pre-optic nuclei, hypothalamus, midbrain, pons, medulla, deep cerebellar nuclei and spinal cord, with tau-immunoreactive pre-tangles in the cortex, hippocampus and basal ganglia. Areas with the most NFT had reactive gliosis. Spinal cord had axonal spheroids, anterior horn cell loss and axonal degeneration in anterior spinal roots. We also saw peripheral neuropathy and skeletal muscle with neurogenic atrophy. Brain and spinal cord contained insoluble tau that co-migrated with insoluble tau from AD and FTDP-17 brains. The phenotype of mice expressing P301L mutant tau mimics features of human tauopathies and provides a model for investigating the pathogenesis of diseases with NFT.
Behavioral disturbances occur in nearly all Alzheimer disease (AD) patients together with an array of cognitive impairments. Prior investigations have failed to demonstrate specific associations ...between them, suggesting an independent, rather than shared, pathophysiology. The objective of this study was to reexamine this issue using an extensive cognitive battery together with a sensitive neurobehavioral and functional rating scale to correlate behavioral syndromes and cognitive domains across the spectrum of impairment in dementia.
Cross-sectional study of comprehensive cognitive and behavioral ratings in subjects with AD and mild cognitive impairment.
Memory disorders research center.
Fifty subjects with AD and 26 subjects with mild cognitive impairment; and their caregivers.
Cognitive rating scales administered included the Mini-Mental State Examination; the Modified Mini-Mental State Examination; the Boston Naming Test; the Benton Visual Retention Test; the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychology Assessment; the Controlled Oral Word Test; the Wechsler Memory Scale logical memory I and logical memory II task; the Wechsler Memory Scale-Revised digit span; the Wechsler Adult Intelligence Scale-Revised digit symbol task; and the Clock Drawing Task together with the Clinical Dementia Rating Scale and the Neuropsychiatric Inventory.
Stepwise regression of cognitive domains with symptom domains revealed significant associations of mood with impaired executive function/speed of processing (Δr = 0.22); impaired working memory (Δr = 0.05); impaired visual memory (Δr = 0.07); and worsened Clinical Dementia Rating Scale (Δr = 0.08). Psychosis was significantly associated with impaired working memory (Δr = 0.13).
Mood symptoms appear to impact diverse cognitive realms and to compromise functional performance. Among neuropsychological indices, the unique relationship between working memory and psychosis suggests a possible common underlying neurobiology.
The cardiac response to increased work includes a reactivation of fetal genes. The response to a decrease in cardiac work is not known. Such information is of clinical interest, because mechanical ...unloading can improve the functional capacity of the failing heart. We compared here the patterns of gene expression in unloaded rat heart with those in hypertrophied rat heart. Both conditions induced a re-expression of growth factors and proto-oncogenes, and a downregulation of the 'adult' isoforms, but not of the 'fetal' isoforms, of proteins regulating myocardial energetics. Therefore, opposite changes in cardiac workload in vivo induce similar patterns of gene response. Reactivation of fetal genes may underlie the functional improvement of an unloaded failing heart.
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