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1.
BMJ Open Sport Exerc Med ; 5(1): e000386, 2019.
Article in English | MEDLINE | ID: mdl-30899543

ABSTRACT

OBJECTIVE: To prospectively investigate the injury profile and the incidence rate per 1000 hours exposure during training and actual league matches in the Nigerian Women's Premier League (NWPL) and to develop an adequate information pool, using the UEFA injury study model in order to develop appropriate injury prevention strategies. METHODS: 241 women footballers from the eight football clubs that participated in the 2015/2016 Nigerian Women Premier league (NWPL) season were selected for the study and prospectively followed for a period of 6 months. The UEFA injury report forms and Competitive Aggressiveness and Anger Scale were sent to the various clubs, and the forms administered on them as at when due. The forms were analysed using descriptive statistics. RESULTS: There was a high incidence rate per 1000 hours of exposure during training sessions (10.98 injuries/1000 hours) and matches (55.56 injuries/1000 hours); the predominant injury type was muscle rupture/strain injuries (35.49%), while moderate severity injuries were the most frequent. The predominant injury mechanism was traumatic injuries caused by contact with other players as a result of a tackle by other players (14.5%). No statistical association was established between the level of aggression and the prevalent types of injury (p=0.63). CONCLUSIONS: The organisers of the league and indeed the referees should ensure that the rules of the game are upheld, and foul or overly aggressive play is penalised. Medical staff and coaches should consider evidence-based injury prevention strategies to reduce the risk of the common injuries sustained in the NWPL.

2.
Sci Adv ; 5(1): eaav1887, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30613782

ABSTRACT

Reconstructions of past Saharan dust deposition in marine sediments provide foundational records of North African climate over time scales of 103 to 106 years. Previous dust records show primarily glacial-interglacial variability in the Pleistocene, in contrast to other monsoon records showing strong precessional variability. Here, we present the first Saharan dust record spanning multiple glacial cycles obtained using 230Th normalization, an improved method of calculating fluxes. Contrary to previous data, our record from the West African margin demonstrates high correlation with summer insolation and limited glacial-interglacial changes, indicating coherent variability in the African monsoon belt throughout the late Pleistocene. Our results demonstrate that low-latitude Saharan dust emissions do not vary synchronously with high- and mid-latitude dust emissions, and they call into question the use of existing Plio-Pleistocene dust records to investigate links between climate and hominid evolution.

3.
Water Sci Technol ; 77(9-10): 2377-2387, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29893726

ABSTRACT

Stormwater retention ponds can play a critical role in mitigating the detrimental effects of urbanization on receiving waters that result from increases in polluted runoff. However, the benthic oxygen demand of stormwater facilities may cause significant hypoxia and trigger the production of hydrogen sulfide (H2S). This process is not well-documented and further research is needed to characterize benthic processes in stormwater retention ponds in order to improve their design and operation. In this study, sediment oxygen demand (SOD), sediment ammonia release (SAR) and sediment sulfide production (SSP) kinetics were characterized in situ and in the laboratory. In situ SOD and SSP data were utilized to develop a stormwater retention pond water sulfide concentration model which demonstrates strong correlation with sulfide concentrations observed in situ (r = 0.724, N = 91, p < 0.001) and in laboratory experiments (r = 0.691, N = 38, p < 0.001). At 4 °C, in situ rates of SOD, SAR and SSP were higher than those measured in laboratory. Sulfate-reducing bacteria (SRB) represented 4.99% of the bacteria present in the top 30 cm of the pond sediment, with Desulfobulbaceae spp., Desulfobacteraceae spp. and Desulfococcus spp. being the dominant SRB taxa identified.


Subject(s)
Ponds , Sulfides/chemistry , Waste Disposal, Fluid/methods , Bacteria/classification , Bacteria/metabolism , Geologic Sediments/microbiology , Kinetics , Models, Theoretical , Water Pollutants, Chemical/chemistry
4.
Water Sci Technol ; 76(2): 286-293, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28726695

ABSTRACT

A combined reed bed-freezing bed (RB-FB) technology was effective at treating septage under Canadian climatic conditions over a 5-year period with average loading rates of 82-104 kg TS/m2/y. Varying hydraulic and solid loading rates as well as the increasing sludge cake with time had little to no effect on treatment efficiency, with almost complete removal of organic matter, solids, heavy metals and nutrients. Filtrate concentrations varied significantly between the freeze-thaw and growing seasons for many parameters, although the differences were not important from a treatment or reuse perspective with filtrate quality similar to a low to medium strength domestic wastewater. The potential to reuse the filtrate as a source of irrigation water will depend upon local regulations. The dewatered sludge cake consistently met biosolids land application standards in terms of pathogen and metals content, with Escherichia coli numbers declining with time as sludge cake depth increased. A combined RB-FB technology can provide a cost-effective solution for septage management in northern rural communities with potential for beneficial reuse of both the filtrate and dewatered sludge cake.


Subject(s)
Cold Climate , Sewage , Waste Disposal, Fluid/methods , Canada , Freezing
5.
Semin Cell Dev Biol ; 67: 48-55, 2017 07.
Article in English | MEDLINE | ID: mdl-28104520

ABSTRACT

Extracellular vesicles (EVs), lipid bilayer-enclosed structures that contain a variety of biological molecules shed by cells, are increasingly becoming appreciated as a major form of cell-to-cell communication. Indeed, EVs have been shown to play important roles in several physiological processes, as well as diseases such as cancer. EVs dock on to the surfaces of recipient cells where they transmit signals from the cell surface and/or transfer their contents into cells to elicit functional responses. EV docking and uptake by cells represent critical, but poorly understood processes. Here, we focus on the mechanisms by which EVs dock and transfer their contents to cells. Moreover, we highlight how these findings may provide new avenues for therapeutic intervention.


Subject(s)
Extracellular Vesicles/metabolism , Gene Expression Regulation, Neoplastic , Membrane Microdomains/metabolism , Neoplasms/metabolism , Tumor Microenvironment/genetics , Antineoplastic Agents/therapeutic use , Biological Transport , Caveolins/genetics , Caveolins/metabolism , Cell Communication , Disease Progression , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Extracellular Vesicles/pathology , Humans , Integrins/genetics , Integrins/metabolism , Membrane Microdomains/pathology , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Tetraspanins/genetics , Tetraspanins/metabolism
6.
Biophys Chem ; 216: 37-43, 2016 09.
Article in English | MEDLINE | ID: mdl-27393931

ABSTRACT

The 39-residue fragment of human prostatic acidic phosphatase (PAP) is found in high concentrations in semen and easily form fibrils. Previous work has shown that fibrillization is accelerated with a deletion of the first 8, mostly charged residues and it was hypothesized that fibrillization depended on the dynamics of these peptides. To test this hypothesis we have measured the intramolecular diffusion of the full length and 8-residue deletion peptides at two different pHs and found a correlation with fibrillization lag time. These results can be explained by a simple kinetic model of the early stages of aggregation in which oligomerization is controlled by the rate of peptide reconfiguration.


Subject(s)
Acid Phosphatase/chemistry , Peptide Fragments/chemistry , Amyloid/chemistry , Diffusion , Humans , Hydrogen-Ion Concentration , Kinetics , Protein Aggregates
7.
Exp Neurol ; 277: 171-177, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26746986

ABSTRACT

Among several genetic mutations known to cause amyotrophic lateral sclerosis (ALS), a hexanucleotide repeat expansion in the C9orf72 gene is the most common. In approximately 30% of C9orf72-ALS cases, 5-methylcytosine (5mC) levels within the C9orf72 promoter are increased, resulting in a modestly attenuated phenotype. The developmental timing of C9orf72 promoter hypermethylation and the reason why it occurs in only a subset of patients remain unknown. In order to model the acquisition of C9orf72 hypermethylation and examine the potential role of 5-hydroxymethylcytosine (5hmC), we generated induced pluripotent stem cells (iPSCs) from an ALS patient with C9orf72 promoter hypermethylation. Our data show that 5mC levels are reduced by reprogramming and then re-acquired upon neuronal specification, while 5hmC levels increase following reprogramming and are highest in iPSCs and motor neurons. We confirmed the presence of 5hmC within the C9orf72 promoter in post-mortem brain tissues of hypermethylated patients. These findings show that iPSCs are a valuable model system for examining epigenetic perturbations caused by the C9orf72 mutation and reveal a potential role for cytosine demethylation.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Induced Pluripotent Stem Cells/physiology , Mutation/genetics , Promoter Regions, Genetic/physiology , Proteins/genetics , 5-Methylcytosine/metabolism , Brain/pathology , C9orf72 Protein , Coculture Techniques , CpG Islands/physiology , Cytosine/analogs & derivatives , DNA Methylation/genetics , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Homeodomain Proteins/metabolism , Humans , Lymphocytes/physiology , Motor Neurons/physiology , Nanog Homeobox Protein , Nestin/metabolism , RNA, Messenger/metabolism , SOXB1 Transcription Factors/metabolism , Time Factors
8.
Environ Technol ; 37(13): 1597-604, 2016.
Article in English | MEDLINE | ID: mdl-26806787

ABSTRACT

This study examined sand filtration as a component of a potato farm wastewater treatment system. Two different sand filter designs, saturated flow and unsaturated flow, were evaluated at three different loading rates: 34, 68, and 136 L m(-2) d(-1). Filter design had a significant effect, with unsaturated flow sand filters having significantly (p < .05) better total suspended solids (TSS) removal (89%) than saturated flow sand filters did (79%). Loading rate also had a significant (p < .05) effect, given that the lowest loading rate had higher mass removal for TSS than the higher loading rates did. Overall, all sand filters removed TSS, 5-d biochemical oxygen demand, and total phosphorus well (62-99%). Total nitrogen removal was twice as high in unsaturated flow filters (53%) than in saturated flow filters (27%), because of the recurring cycle of aerobic and anaerobic conditions during sand saturation and drying in unsaturated flow sand filters.


Subject(s)
Solanum tuberosum , Waste Disposal, Fluid/methods , Wastewater/chemistry , Agriculture/methods , Farms , Filtration , Nitrogen/analysis , Phosphorus/analysis , Silicon Dioxide , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/prevention & control
9.
Mol Cell Neurosci ; 68: 244-57, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26284979

ABSTRACT

BACKGROUND: GABAergic synaptic transmission is known to play a critical role in the assembly of neuronal circuits during development and is responsible for maintaining the balance between excitatory and inhibitory signaling in the brain during maturation into adulthood. Importantly, defects in GABAergic neuronal function and signaling have been linked to a number of neurological diseases, including autism spectrum disorders, schizophrenia, and epilepsy. With patient-specific induced pluripotent stem cell (iPSC)-based models of neurological disease, it is now possible to investigate the disease mechanisms that underlie deficits in GABAergic function in affected human neurons. To that end, tools that enable the labeling and purification of viable GABAergic neurons from human pluripotent stem cells would be of great value. RESULTS: To address the need for tools that facilitate the identification and isolation of viable GABAergic neurons from the in vitro differentiation of iPSC lines, a cell type-specific promoter-driven fluorescent reporter construct was developed that utilizes the human vesicular GABA transporter (hVGAT) promoter to drive the expression of mCherry specifically in VGAT-expressing neurons. The transduction of iPSC-derived forebrain neuronal cultures with the hVGAT promoter-mCherry lentiviral reporter construct specifically labeled GABAergic neurons. Immunocytochemical analysis of hVGAT-mCherry expression cells showed significant co-labeling with the GABAergic neuronal markers for endogenous VGAT, GABA, and GAD67. Expression of mCherry from the VGAT promoter showed expression in several cortical interneuron subtypes to similar levels. In addition, an effective and reproducible protocol was developed to facilitate the fluorescent activated cell sorting (FACS)-mediated purification of high yields of viable VGAT-positive cells. CONCLUSIONS: These studies demonstrate the utility of the hVGAT-mCherry reporter construct as an effective tool for studying GABAergic neurons differentiated in vitro from human pluripotent stem cells. This approach could provide a means of obtaining large quantities of viable GABAergic neurons derived from disease-specific hiPSCs that could be used for functional assays or high-throughput screening of small molecule libraries.


Subject(s)
GABAergic Neurons/metabolism , Luminescent Proteins/metabolism , Pluripotent Stem Cells/physiology , Vesicular Inhibitory Amino Acid Transport Proteins/metabolism , Calbindin 2/metabolism , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Survival , Cells, Cultured , Flow Cytometry , Glial Cell Line-Derived Neurotrophic Factor/pharmacology , Glial Fibrillary Acidic Protein/metabolism , Glutamate Decarboxylase/metabolism , Humans , Luminescent Proteins/genetics , Mutation/genetics , Nerve Growth Factor/pharmacology , Parvalbumins/metabolism , Pluripotent Stem Cells/drug effects , Prosencephalon/cytology , Somatostatin/metabolism , Synapsins/metabolism , Transfection , Vesicular Inhibitory Amino Acid Transport Proteins/genetics , Red Fluorescent Protein
10.
Exp Neurol ; 271: 241-50, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26099177

ABSTRACT

A hexanucleotide repeat expansion residing within the C9ORF72 gene represents the most common known cause of amyotrophic lateral sclerosis (ALS) and places the disease among a growing family of repeat expansion disorders. The presence of RNA foci, repeat-associated translation products, and sequestration of RNA binding proteins suggests that toxic RNA gain-of-function contributes to pathology while C9ORF72 haploinsufficiency may be an additional pathological factor. One viable therapeutic strategy for treating expansion diseases is the use of small molecule inhibitors of epigenetic modifier proteins to reactivate expanded genetic loci. Indeed, previous studies have established proof of this principle by increasing the drug-induced expression of expanded (and abnormally heterochromatinized) FMR1, FXN and C9ORF72 genes in respective patient cells. While epigenetic modifier proteins are increasingly recognized as druggable targets, there have been few screening strategies to address this avenue of drug discovery in the context of expansion diseases. Here we utilize a semi-high-throughput gene expression based screen to identify siRNAs and small molecule inhibitors of epigenetic modifier proteins that regulate C9ORF72 RNA in patient fibroblasts, lymphocytes and reprogrammed motor neurons. We found that several bromodomain small molecule inhibitors increase the expression of C9ORF72 mRNA and pre-mRNA without affecting repressive epigenetic signatures of expanded C9ORF72 alleles. These data suggest that bromodomain inhibition increases the expression of unexpanded C9ORF72 alleles and may therefore compensate for haploinsufficiency without increasing the production of toxic RNA and protein products, thereby conferring therapeutic value.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Lymphocytes/metabolism , Proteins/genetics , Adenosine Triphosphate , Benzodiazepines/pharmacology , C9orf72 Protein , Cell Cycle/drug effects , Cell Line, Transformed , DNA Methylation/drug effects , DNA Methylation/genetics , Deoxycytidine/pharmacology , Enzyme Inhibitors/pharmacology , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Gene Library , Humans , Lymphocytes/drug effects , Mutation/genetics , Neurons/drug effects , Neurons/metabolism , RNA, Messenger/metabolism , RNA, Small Interfering/genetics , Transfection
11.
Biochemistry ; 53(20): 3267-77, 2014 May 27.
Article in English | MEDLINE | ID: mdl-24811874

ABSTRACT

SEM1(86-107) is a 22-residue peptide corresponding to residues 86-107 in the semenogelin I protein. SEM1(86-107) is an abundant component of freshly liquefied semen and forms amyloid fibrils capable of enhancing HIV infection. To probe the factors affecting fibril formation and gain a better understanding of how differences in pH between semen and vaginal fluid affect fibril stability, this study determined the effect of pH on SEM1(86-107) fibril formation and dissociation. The SEM1(86-107) fibril structure (i.e., residues that comprise the fibrillar core) was also probed using hydrogen-deuterium exchange mass spectrometry (HDXMS) and hydroxyl radical-mediated protein modification. The average percent exposure to hydroxyl radical-mediated modification in the SEM1(86-107) fibrils was determined without requiring tandem mass spectrometry spectral acquisition or complete separation of modified peptides. It was found that the residue exposures calculated from HDXMS and hydroxyl radical-mediated modification were similar. These techniques demonstrated that three regions of SEM1(86-107) comprise the amyloid fibril core and that positively charged residues are exposed, suggesting that electrostatic interactions between SEM1(86-107) and HIV or the cell surface may be responsible for mediating HIV infection enhancement by the SEM1(86-107) fibrils.


Subject(s)
HIV Infections/metabolism , HIV-1 , Semen/chemistry , Semen/physiology , Seminal Vesicle Secretory Proteins/chemistry , Seminal Vesicle Secretory Proteins/genetics , Amino Acid Sequence , Amyloid/chemistry , Amyloid/genetics , HIV Infections/genetics , Humans , Male , Molecular Sequence Data
12.
Protein Expr Purif ; 88(2): 196-200, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23314347

ABSTRACT

PAPf39 is a 39 residue peptide fragment from human prostatic acidic phosphatase that forms amyloid fibrils in semen. These fibrils have been implicated in facilitating HIV transmission. To enable structural studies of PAPf39 by NMR spectroscopy, efficient methods allowing the production of milligram quantities of isotopically labeled peptide are essential. Here, we report the high-yield expression and purification of uniformly (13)C- and (15)N-labeled PAPf39 peptide, through expression as a fusion to ubiquitin at the N-terminus and an intein at the C-terminus. This allows the study of the PAPf39 monomer conformational ensemble by NMR spectroscopy. To this end, we performed the NMR chemical shift assignment of the PAPf39 peptide in the monomeric state at low pH.


Subject(s)
Amyloid/chemistry , Amyloid/genetics , Peptide Fragments/chemistry , Peptide Fragments/genetics , Protein Tyrosine Phosphatases/chemistry , Protein Tyrosine Phosphatases/genetics , Amino Acid Sequence , Amyloid/isolation & purification , Amyloid/metabolism , Escherichia coli/genetics , Humans , Inteins , Molecular Sequence Data , Nuclear Magnetic Resonance, Biomolecular , Peptide Fragments/isolation & purification , Peptide Fragments/metabolism , Protein Conformation , Protein Tyrosine Phosphatases/isolation & purification , Protein Tyrosine Phosphatases/metabolism , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Ubiquitin/genetics , Ubiquitin/isolation & purification
13.
Biochemistry ; 51(51): 10127-36, 2012 Dec 21.
Article in English | MEDLINE | ID: mdl-23215256

ABSTRACT

PAPf39, a 39-residue peptide fragment from human prostatic acidic phosphatase, has been shown to form amyloid fibrils in semen (SEVI), which increase HIV infectivity by up to 5 orders of magnitude. The sequence of the PAPf39 fibrillar core was identified using hydrogen-deuterium exchange (HDX) mass spectrometry and protease protection assays. The central and C-terminal regions are highly protected from HDX and proteolytic cleavage and, thus, are part of the fibrillar core. Conversely, the N-terminal region is unprotected from HDX and proteolytic cleavage, suggesting that it is exposed and not part of the fibrillar core. This finding was tested using two N-terminal truncated variants, PAPf39Δ1-8 and PAPf39Δ1-13. Both variants formed amyloid fibrils at neutral pH. However, these variants showed a markedly different pH dependence of fibril formation versus that of PAPf39. PAPf39 fibrils can form at pH 7.7, but not at pH 5.5 or 2.5, while both N-terminally truncated variants can form fibrils at these pH values. Thus, the N-terminal region is not necessary for fibril formation but modulates the pH dependence of PAPf39 fibril formation. PAPf39Δ1-8 and PAPf39Δ1-13 are capable of seeding PAPf39 fibril formation at neutral pH, suggesting that these variants are structurally compatible with PAPf39, yet no mixed fibril formation occurs between the truncated variants and PAPf39 at low pH. This suggests that pH affects the PAPf39 monomer conformational ensemble, which is supported by far-UV circular dichroism spectroscopy. A conceptual model describing the pH dependence of PAPf39 aggregation is proposed and provides potential biological implications.


Subject(s)
Amyloid/chemistry , Peptide Fragments/chemistry , Protein Tyrosine Phosphatases/chemistry , Acid Phosphatase , Amino Acid Sequence , Circular Dichroism , Deuterium Exchange Measurement , Humans , Hydrogen-Ion Concentration , Male , Molecular Sequence Data , Protein Conformation
14.
Mini Rev Med Chem ; 12(11): 1063-70, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22924484

ABSTRACT

Herein we discuss the effects of hormones on reproduction, but with a focus on the ripples that emanate from the main effects. That is, the role of hormones in reproductive events is both well-known and well accepted; less studied and understood are effects that appear to be ancillary to the primary objectives of the hormonal effects, which support, complement and extend their primary effects. We present evidence for how the hormonal stimulation of pregnancy constructs the maternal brain; makes it more efficient; enhances cognition; regulates stress responsiveness; modifies sensory systems (we discuss mainly olfaction); neurogenesis; and learning. Thus, steroid and other hormones and neuropeptides restructure the nervous system, particularly of females, to produce and regulate maternal behavior as well as behaviors and physiological systems that contribute to and support what is arguably the primary function of the hormones: survival and effective nurturance of the female's metabolic and genetic investment.


Subject(s)
Brain/physiology , Gonadal Steroid Hormones/metabolism , Reproduction , Animals , Brain/metabolism , Female , Humans , Learning , Neurogenesis , Olfactory Perception , Pregnancy , Stress, Physiological
15.
J Neuroendocrinol ; 23(11): 1177-87, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21933288

ABSTRACT

The hormones and experiences of pregnancy, parturition and lactation have been shown to dramatically remodel the female rat's hippocampus, potentially enhancing behaviours critical for meeting the increased demands of motherhood. Previous work in our laboratory has also suggested that pup exposure, apart from pregnancy and lactation, constitutes an important influence on ancillary maternal behaviour (e.g. foraging behaviour). In the present study, we press the parental model further by examining the effect of pup exposure on the hippocampus of males from a biparental mouse species, the California mice (Peromyscus californicus). Males were either Fathers (i.e. first-time fathers housed with a female from mating until 7 days after parturition), pup-exposed virgins (PEV; i.e. sexually naïve males briefly exposed to pups daily for 7 days) or Virgins (i.e. never exposed to females or pups). A dry-land maze (DLM), as used for assessing spatial learning, was employed to determine the foraging abilities of the males. The results indicated that, on the most challenging day of testing (i.e. acquisition day), California mouse Fathers demonstrated superior memory for the task compared to PEVs and Virgins. In addition to the behavioural data, significantly more fos-immunoreactivity was observed in the CA1, CA3 and dentate gyrus regions of the hippocampi of Fathers than PEVs or Virgins in response to the probe trial. Additionally, a trend for altered performance on the DLM was observed in the PEVs on the last day of testing, which was accompanied by the highest levels of nestin-immunoreactivity, an indicant of neuroplasticity, of the three groups. In summary, these data suggest that, in accordance with previous observations of maternal rats, the paternal brain is similarly influenced by parental experience, as demonstrated by accompanying modifications to relevant neurobiological and behavioural responses.


Subject(s)
Behavior, Animal , Fathers , Task Performance and Analysis , Animals , Female , Immunohistochemistry , Male , Maze Learning , Mice , Neuronal Plasticity
16.
J Neuroendocrinol ; 23(11): 974-83, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21790810

ABSTRACT

In the rat, the change from a virgin/nulliparous female to the maternal animal takes place at many levels. A subtle developmental wave washes over the female nervous system and transforms her from largely self-centred to offspring-directed, from personal care and protection to care of genetically-related offspring, from indifference to ardour. Such change is preceded by substantial and apparently permanent neural alterations, the depth of which results in the maternal brain, and is the basis of the present review. The neuroplasticity of pregnancy, inherent to the female brain and, we believe, representative of the full expression of the female nervous system's capacity, is a result of significant hormonal and other neurochemical actions. It results in the striking brain changes that are associated with, and necessary for, successful reproduction. We discuss some of these changes and their ramifications. Collectively, they represent the culmination of mammalian evolution and have led to the development of the social brain characteristic of higher orders of mammal, including the human. We also examine different facets of the maternal brain, beginning with a review of the genes involved in maternal behaviour, and in the subsequent 'expression' of the maternal brain. We next discuss olfaction and the manner in which this major sense draws from the rich sensory milieu of the mother to regulate and support maternal behaviour. Last, we discuss the 'whys' of maternal behaviour, a theoretical foray into the reasons for such substantial maternal brain alterations. We focus on the male's potential role as the raison d'etre for the manifest alterations in his mate's brain. In the end, it is clear that the female brain undergoes a significant reorganisation en route to motherhood, the results of which are deep and enduring.


Subject(s)
Behavior , Brain/physiology , Mothers , Animals , Biological Evolution , Brain/metabolism , Female , Gene Expression , Humans , Male , Signal Transduction , Smell
17.
Water Sci Technol ; 62(3): 475-83, 2010.
Article in English | MEDLINE | ID: mdl-20705993

ABSTRACT

The objective of this study was to determine the effectiveness of anaerobic digestion in the treatment of polyphenols (PP) present in olive mill wastewater (OMW) and wine distillery wastewater (WDW). Anaerobic Toxicity Assay (ATA) was conducted to assess the impact of the most representative phenolic compounds present in OMW and WDW: catechol, tannins and p-Coumaric acid, on biogas production. The results from this study show that tannins do not present any inhibitory effect on methanogenesis at a concentration level of 1,664 ppm, whereas catechol has an inhibitory effect at 1,664 ppm. In addition, p-Coumaric acid was strongly inhibitory at 50 ppm. The co-digestion of OMW and WDW with other effluents was proposed as a solution for reducing the load of PP in the anaerobic medium. Biochemical methane potential (BMP) tests were carried out for dairy cattle manure and mixtures of five PP. A central composite design was implemented on the BMP tests to model the biogas production response and the degradation kinetics of PP. The co-digestion of WDW with cattle manure and/or whey was also investigated in BMP tests. The results show that the digestion was optimal at a ratio of 16: 64: 20 (WDW: manure: inoculum) with a maximum biogas yield of 172 mL/g of VS and 66% COD removal.


Subject(s)
Flavonoids/chemistry , Industrial Waste , Manure/analysis , Milk Proteins/chemistry , Models, Statistical , Phenols/chemistry , Wine/analysis , Anaerobiosis , Animals , Bioreactors , Cattle , Dairying , Flavonoids/metabolism , Molecular Structure , Phenols/metabolism , Polyphenols , Time Factors , Waste Disposal, Fluid/methods , Water Pollutants, Chemical , Water Purification , Whey Proteins
18.
Biochemistry ; 48(48): 11582-91, 2009 Dec 08.
Article in English | MEDLINE | ID: mdl-19902966

ABSTRACT

PAPf39 is a 39-residue peptide fragment from the sequence of human prostatic acidic phosphatase. This peptide was shown to form amyloid-like fibrils, which have been implicated in facilitating semen-mediated HIV transmission. Thus understanding molecular details of PAPf39 peptide fibril formation may aid in elucidating the mechanism of how PAPf39 fibrils are involved in HIV etiology. To this end, the kinetics of PAPf39 peptide fibrillization was studied using a battery of biophysical methods (atomic force microscopy, ThT fluorescence assays, far-UV circular dichroism spectroscopy, deep-UV resonance Raman spectroscopy, size exclusion chromatography, analytical ultracentrifugation, and small-angle X-ray scattering). It has been shown that fibril formation follows a nucleation-dependent elongation mechanism. Several critical factors for fibrillization have been identified. It was shown that agitation and/or seeding is required for fibril formation at 37 degrees C and neutral pH, with an additional requirement of a salt concentration above approximately 100 mM. Fibril formation by the PAPf39 peptide is inhibited by low pH or by low salt concentration at neutral pH. These observations suggest that the nucleation and fibrillization of the PAPf39 peptide are a tug-of-war between the interactions formed upon agitation and the electrostatic interactions, modulated by pH and salt concentration.


Subject(s)
Amyloid/metabolism , Peptide Fragments/metabolism , Protein Tyrosine Phosphatases/metabolism , Acid Phosphatase , Amino Acid Sequence , Amyloid/chemistry , Amyloid/isolation & purification , Chromatography, Gel , Circular Dichroism , Hydrogen-Ion Concentration , Kinetics , Microscopy, Atomic Force , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/isolation & purification , Protein Tyrosine Phosphatases/chemistry , Scattering, Radiation , Spectrometry, Fluorescence , Spectrum Analysis, Raman , Temperature , Ultracentrifugation , X-Rays
19.
Water Sci Technol ; 59(12): 2455-62, 2009.
Article in English | MEDLINE | ID: mdl-19542652

ABSTRACT

A tracer study is an efficient method of determining flow dynamics within a constructed wetland. In previous studies, a number of tracer studies have been carried out on various constructed wetlands covering a wide range of configurations. From these tracer studies it is evident that all constructed wetlands perform differently and generally with less efficiency than assumed by theoretical design computations. During the summer of 2004, a tracer study was performed on a constructed wetland located in Embrun, Ontario (Canada) treating milkhouse wastewater and agricultural runoff to determine its actual hydraulic performance. Sediment height and vegetation density profiles were also obtained and examined to explain the preferential flow pathways that were observed during the tracer analysis. It was determined that the constructed wetland had an effective treatment area representing 79% of the total area, and that the hydraulic efficiency of the system was 74%. Examination of the sediment height and vegetation density profiles resulted in no evidence of physical pathways that could be attributed to the establishment of preferential flow. The hydraulic efficiency was therefore attributed to the inflow and outflow layout of the constructed wetland cell, combined with wind induced mixing.


Subject(s)
Agriculture , Waste Disposal, Fluid/methods , Wetlands , Water Movements
20.
Water Sci Technol ; 56(3): 151-8, 2007.
Article in English | MEDLINE | ID: mdl-17802850

ABSTRACT

A pilot scale treatment system was established in 2002 at the Laflèche Landfill in Eastern Ontario, Canada. The system consists of a series of treatment steps: a stabilisation basin (10,000 m3), a woodland peat trickling filter (5,200 m2), a subsurface flow constructed wetland planted in Phragmites sp. (2,600 m2), a surface flow constructed wetland planted in Typha sp. (3,600 m2) and a polishing pond (3,600 m2). The system operates from May to December with leachate being recycled within the landfill during the winter months. Hydraulic loading was increased three-fold over four operating seasons with nitrogen and organic mass loading increasing six-fold. Excellent removal efficiencies were observed with 93% BOD5, 90% TKN and 97% NH4-N removed under the highest loading conditions. Almost complete denitrification was observed throughout the treatment system with NO3-N concentrations never exceeding 5mg L(-1). The peat filter reached treatment capacity at a hydraulic loading of 4cm d(-1) and organic loading rate of 42 kg BOD ha(-1) d(-1), which is consistent with design criteria for vertical flow wetland systems and intermittent sand filters, The first order plug flow kinetic model was effective at describing TKN and ammonium removal in the SSF and FWS wetlands when background concentrations were taken into account. Ammonium removal k-values were consistent with the literature at 52.6 and 57.7 yr(-1) for the SSF and FWS wetlands, respectively, while TKN k-values at 6.9 and 7.7 yr(-1) were almost an order of magnitude lower than literature values, suggesting that leachate TKN could contain refractory organics not found in domestic wastewater.


Subject(s)
Nitrogen/isolation & purification , Water Pollutants, Chemical/chemistry , Water Purification/methods , Wetlands , Biodegradation, Environmental , Canada , Environment Design , Filtration/methods , Kinetics , Pilot Projects , Water Movements
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