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1.
J Dairy Sci ; 102(2): 1832-1846, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30580949

ABSTRACT

Canadian dairy producers have an increasing interest in recycled manure solids (RMS) as bedding material because of reduced availability of traditional bedding resources. Information regarding methods to obtain RMS and composition of RMS is very limited. Hence, a 2-part investigation was developed to compare the performances of 3 mechanical solid-liquid manure separators (part I) and 4 composting methods (part II; companion paper in this issue) for the production of high quality RMS. In this first study, a roller press, a screw press, and a decanter centrifuge were tested for the separation of slurry manure from a commercial dairy farm. During the experiment, the quantity of slurry manure processed and the volume and mass of the liquid and solid fractions were measured. The energy consumption of each separator was recorded, and samples of the slurry, liquid, and solid effluents were collected for analysis. The type of separator did not significantly influence the chemical and bacteriological composition of RMS produced. The choice of a separator for Canadian dairy producers should thus be based on the equipment cost and its capacity, targeted solids dry matter (DM) content and structure, and fertilizing quality of the separated liquid. The decanter centrifuge produced the solid phase with the highest DM and best separation efficiencies for DM, N, and P. However, its low production capacity (1.5 m3/h vs. 9.1-20.3 m3/h) combined with its high acquisition cost (Can$145,000 vs. Can$75,000) and energy consumption (4.99 kWh/m3 vs. 0.10-0.35 kWh/m3) reduce its technical and profitability values. Besides, the centrifuge produced fine structured RMS and a low-quality liquid fraction, not suitable as dairy cow bedding and fertilizer, respectively. Both presses reached acceptable production capacity at a minimal operation cost. However, the poor performance in terms of DM (25%) of the model of screw press used in this study produced RMS unsuitable for immediate use without further processing. The model of roller press used in this study had the advantages of almost reaching the recommended DM content in RMS (>34%), being flexible in terms of inputs, and producing fluffy RMS. Nevertheless, its compression process seemed to allow greater passage of solids into the liquid fraction compared with the screw press. Part II of this work explores different composting methods to reduce the health risks associated with screw-pressed RMS before their use as bedding.


Subject(s)
Animal Husbandry/methods , Bedding and Linens/veterinary , Cattle/physiology , Manure/analysis , Recycling/methods , Animal Husbandry/instrumentation , Animals , Canada , Farms , Female , Male
2.
Psychol Med ; 46(12): 2605-15, 2016 09.
Article in English | MEDLINE | ID: mdl-27353541

ABSTRACT

BACKGROUND: Language use is of increasing interest in the study of mental illness. Analytical approaches range from phenomenological and qualitative to formal computational quantitative methods. Practically, the approach may have utility in predicting clinical outcomes. We harnessed a real-world sample (blog entries) from groups with psychosis, strong beliefs, odd beliefs, illness, mental illness and/or social isolation to validate and extend laboratory findings about lexical differences between psychosis and control subjects. METHOD: We describe the results of two experiments using Linguistic Inquiry and Word Count software to assess word category frequencies. In experiment 1, we compared word use in psychosis and control subjects in the laboratory (23 per group), and related results to subject symptoms. In experiment 2, we examined lexical patterns in blog entries written by people with psychosis and eight comparison groups. In addition to between-group comparisons, we used factor analysis followed by clustering to discern the contributions of strong belief, odd belief and illness identity to lexical patterns. RESULTS: Consistent with others' work, we found that first-person pronouns, biological process words and negative emotion words were more frequent in psychosis language. We tested lexical differences between bloggers with psychosis and multiple relevant comparison groups. Clustering analysis revealed that word use frequencies did not group individuals with strong or odd beliefs, but instead grouped individuals with any illness (mental or physical). CONCLUSIONS: Pairing of laboratory and real-world samples reveals that lexical markers previously identified as specific language changes in depression and psychosis are probably markers of illness in general.


Subject(s)
Personal Narratives as Topic , Psychotic Disorders/physiopathology , Psychotic Disorders/psychology , Schizophrenia/physiopathology , Schizophrenic Psychology , Verbal Behavior , Adult , Depression/physiopathology , Depression/psychology , Female , Humans , Male , Middle Aged , Young Adult
3.
Curr Oncol ; 22(2): 156-63, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25908914

ABSTRACT

Across Canada, introduction of the Pap test for cervical cancer screening, followed by mammography for breast cancer screening and, more recently, the fecal occult blood test for colorectal cancer screening, has contributed to a reduction in cancer mortality. However, another contribution of screening has been disparities in cancer mortality between certain populations. Here, we explore the disparities associated with breast and cervical cancer screening and preliminary data concerning disparities in colorectal cancer screening. Although some disparities in screening utilization have been successfully reduced over time (for example, mammography and Pap test screening in rural and remote populations), screening utilization data for other populations (for example, low-income groups) clearly indicate that disparities have existed and continue to exist across Canada. Organized screening programs in Canada have been able to successfully engage 80% of women for regular cervical cancer screening and 70% of women for regular mammography screening, but of the women who remain to be reached or engaged in regular screening, those with the least resources, those who are the most isolated, and those who are least culturally integrated into Canadian society as a whole are over-represented. Population differences are also observed for utilization of colorectal cancer screening services. The research literature on interventions to promote screening utilization provides some evidence about what can be done to increase participation in organized screening by vulnerable populations. Adaption and adoption of evidence-based screening promotion interventions can increase the utilization of available screening services by populations that have experienced the greatest burden of disease with the least access to screening services.

4.
Ann Bot ; 111(2): 207-14, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23235696

ABSTRACT

BACKGROUND AND AIMS: Three ecological relationships are possible between co-flowering plant species; they may have no effect on one another, compete for pollination services, or facilitate one another by attracting more pollinators to the area. In this study, the pollinator-mediated relationship between two mangrove species with overlapping flowering phenologies was investigated in one south Florida community. METHODS: Pollinator observations were recorded between 0900 h and 1700 h during June and July, 2008-2010. Insect visitation rates to Avicennia germinans and Laguncularia racemosa were estimated from 522 observation intervals of 10 min during three phenological time periods, when each species flowered alone and when they co-flowered. The number of timed intervals varied between years due to differences in flowering phenology, from four to 42 for A. germinans and from nine to 94 for L. racemosa. KEY RESULTS: Avicennia germinans began flowering first in all years, and insect visitation rates were significantly greater to A. germinans than to L. racemosa (P<0Ā·001). Flowers of both species received visits from bees, wasps, flies and butterflies; Apis mellifera was the most common floral visitor to both species. Visitation rates to L. racemosa increased significantly when A. germinans stopped flowering (P<0Ā·001). However, there was no significant change in visitation rates to A. germinans after L. racemosa began flowering (P=0Ā·628). CONCLUSIONS: When they co-flowered, A. germinans outcompeted L. racemosa for pollinators. Laguncularia racemosa hermaphrodites self-pollinate autogamously when not visited by insects, so reduced visitation to L. racemosa flowers reduced the frequency of outcrossing and increased the frequency of selfing. Reduced outcrossing limits male reproductive success in this androdioecious species, which could lead to changes in the breeding system. The degree of overlap in flowering phenologies varied between years, so the effect on the mating and breeding system may differ between years.


Subject(s)
Avicennia/physiology , Avicennia/parasitology , Bees/physiology , Combretaceae/physiology , Combretaceae/parasitology , Animals , Breeding , Feeding Behavior , Florida , Flowers/parasitology , Flowers/physiology , Insecta/physiology , Pollination , Reproduction , Species Specificity
5.
J Bacteriol ; 194(3): 740-1, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22247535

ABSTRACT

Edwardsiella ictaluri is the cause of extensive mortalities and economic losses to the channel catfish industry of the southeast United States. Here we report the complete genome of Edwardsiella ictaluri 93-146. Whole-genome sequence analysis of E. ictaluri provides a tool for understanding the genomic regions specific to the species and the Edwardsiella genus.


Subject(s)
Edwardsiella ictaluri/genetics , Enterobacteriaceae Infections/veterinary , Fish Diseases/microbiology , Genome, Bacterial , Ictaluridae , Sepsis/veterinary , Animals , Base Sequence , Disease Outbreaks , Edwardsiella ictaluri/classification , Edwardsiella ictaluri/isolation & purification , Enterobacteriaceae Infections/epidemiology , Enterobacteriaceae Infections/microbiology , Fish Diseases/epidemiology , Molecular Sequence Data , Sepsis/epidemiology , Sepsis/microbiology , United States/epidemiology
6.
Nat Commun ; 12(1): 3126, 2021 05 25.
Article in English | MEDLINE | ID: mdl-34035259

ABSTRACT

Hybridization and polyploidization are powerful mechanisms of speciation. Hybrid speciation often coincides with whole-genome duplication (WGD) in eukaryotes. This suggests that WGD may allow hybrids to thrive by increasing fitness, restoring fertility and/or increasing access to adaptive mutations. Alternatively, it has been suggested that hybridization itself may trigger WGD. Testing these models requires quantifying the rate of WGD in hybrids without the confounding effect of natural selection. Here we show, by measuring the spontaneous rate of WGD of more than 1300 yeast crosses evolved under relaxed selection, that some genotypes or combinations of genotypes are more prone to WGD, including some hybrids between closely related species. We also find that higher WGD rate correlates with higher genomic instability and that WGD increases fertility and genetic variability. These results provide evidence that hybridization itself can promote WGD, which in turn facilitates the evolution of hybrids.


Subject(s)
Gene Duplication , Genome, Fungal/genetics , Hybridization, Genetic , Saccharomyces/genetics , Adaptation, Physiological/genetics , Diploidy , Evolution, Molecular , Genetic Variation/genetics , Genomic Instability/genetics , Mutation Rate , Phylogeny , Polyploidy , Saccharomyces/classification , Saccharomyces cerevisiae/genetics , Species Specificity
7.
J Exp Med ; 193(10): 1189-98, 2001 May 21.
Article in English | MEDLINE | ID: mdl-11369790

ABSTRACT

We show that cytotoxic T lymphocytes (CTLs) infiltrating a kidney tumor recognize a peptide encoded by an alternative open reading frame (ORF) of the macrophage colony-stimulating factor (M-CSF) gene. Remarkably, this alternative ORF, which is translated in many tumors concurrently with the major ORF, is also translated in some tissues that do not produce M-CSF, such as liver and kidney. Such a dissociation of the translation of two overlapping ORFs from the same gene is unexpected. The antigenic peptide encoded by the alternative ORF is presented by human histocompatibility leukocyte antigen (HLA)-B*3501 and has a length of 14 residues. Peptide elution indicated that tumor cells naturally present this 14 mer, which is the longest peptide known to be recognized by CTLs. Binding studies of peptide analogues suggest that it binds by its two extremities and bulges out of the HLA groove to compensate for its length.


Subject(s)
Antigens, Neoplasm/genetics , Lymphocytes, Tumor-Infiltrating/immunology , Macrophage Colony-Stimulating Factor/genetics , Open Reading Frames , Peptides/genetics , T-Lymphocytes, Cytotoxic/immunology , Amino Acid Sequence , Antigens, Neoplasm/immunology , Base Sequence , Carcinoma, Renal Cell/immunology , Cytotoxicity, Immunologic , HLA-B35 Antigen , Humans , Kidney Neoplasms , Macrophage Colony-Stimulating Factor/immunology , Molecular Sequence Data , Peptides/immunology , Protein Biosynthesis
8.
Sci Total Environ ; 726: 138515, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32481216

ABSTRACT

Since the mid-1990s, the decline of the yellow perch population of Lake Saint-Pierre (hereinafter LSP) in Quebec, Canada has been the subject of several research programs. The combined effect of habitat deterioration, the presence of invasive species, and poor water quality negatively affected the yellow perch population in this lake. In 2013, we sampled yellow perch (larvae, juveniles and adults) at six sites along the St. Lawrence River representing a gradient of increasing human influences from upstream to downstream and measured several biomarkers including retinoid compounds (vitamin A). In the most contaminated sites (LSP, north and south shores), we found that retinoid stores were decreased in all three stages of development. To corroborate these results and to test other biomarkers, we once again sampled yellow perch (adults only) from the same sites. Results from our 2014 and 2015 samplings confirmed that LSP yellow perch appeared to be at a disadvantage compared to fish from upstream populations. Individuals from LSP have lower acetylcholinesterase (AChE) activity as well as lower retinoid levels in liver and plasma. These fish were also marked by lower levels of antioxidants such as lycopene and vitamin E. A discriminant analysis of this set of results confirmed that the yellow perch of the LSP could be easily discriminated from those of the other sites (2014 and 2015) on the basis of liver retinoid and, to a lesser extent, of the liver tocopherol and protein concentration of the muscle, as well as AChE activity and DROH (all-trans-3,4-dehydroretinol) measured in plasma.


Subject(s)
Perches , Water Pollutants, Chemical/analysis , Animals , Biomarkers , Canada , Health Status , Humans , Quebec
9.
Science ; 260(5114): 1653-5, 1993 Jun 11.
Article in English | MEDLINE | ID: mdl-17810208

ABSTRACT

Polycrystalline samples of the chalcopyrites CulnS(2), CulnSe(2), and CulnSSe were Prepared from stoichiometric mixtures of the pure elements by microwave irradiation. The reactions were performed in sealed quartz tubes in as few as 3 minutes. The products were analyzed by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray analysis, and x-ray photoelectron spectroscopy. The surface morphology and shape of the particles produced by this method suggest that the products are formed from liquid melts. This method could be applied to the production of bulk chalcopyrite as sources for thin film growth.

10.
Science ; 157(3790): 808-9, 1967 Aug 18.
Article in English | MEDLINE | ID: mdl-17842784

ABSTRACT

Ultrasensitive radars and uninstrumented jet aircraft in concert have probed regions of the clear atmosphere in search of clear-air turbulence. All sources of clear-air radar echoes above 6 kilometers that were probed simultaneously by the aircraft were found to be turbulent.

11.
Leukemia ; 31(1): 136-142, 2017 01.
Article in English | MEDLINE | ID: mdl-27560108

ABSTRACT

Stem cell transplantation (SCT), an effective therapy for amyloid light chain (AL) amyloidosis patients, is associated with low treatment-related mortality (TRM) with appropriate patient selection and risk-adapted dosing of melphalan (RA-SCT). Consolidation after SCT increases hematologic complete response (CR) rates and may improve overall survival (OS) for patients with

Subject(s)
Amyloidosis/drug therapy , Amyloidosis/mortality , Melphalan/administration & dosage , Amyloidosis/therapy , Bortezomib/therapeutic use , Consolidation Chemotherapy/methods , Disease-Free Survival , Follow-Up Studies , Humans , Immunoglobulin Light Chains , Middle Aged , Remission Induction , Retrospective Studies , Risk Adjustment , Stem Cell Transplantation , Survival Rate
12.
Neuroscience ; 139(4): 1435-48, 2006.
Article in English | MEDLINE | ID: mdl-16517089

ABSTRACT

Gene expression profiling of suprachiasmatic nucleus, ventrolateral preoptic area and the lateral hypothalamus was used to identify genes regulated diurnally in the hypothalamus of Mus musculus. The putative transcription regulator, cysteine and histidine-rich domain-containing, zinc binding protein 1, which had not been previously described in brain, was found to cycle diurnally in hypothalamus and forebrain with peak levels of mRNA expression during the dark phase. mRNA for the brain-type fatty acid binding protein 7 was found to change rhythmically in hypothalamic and extra-hypothalamic brain regions reaching peak levels early in the light phase suggesting that lipid metabolism is under circadian regulation in astrocytes. Rhythmically expressed genes in suprachiasmatic nucleus identified here were compared with previous reports in a meta-analysis. Genes held in common included fabp7, and the period gene, Per2. Also identified were genes implicated in guanosine-mediated signaling pathways that included dexamethasone-induced ras-related protein one (dexras1), regulator of G-protein signaling (rgs) 16, and ras-like family member 11b. Northern blotting confirmed diurnal changes in mRNA expression in the hypothalamus for these genes. Ras-like family member 11b was examined in more detail using in situ hybridization and antiphase diurnal changes in expression in suprachiasmatic nucleus and arcuate nucleus were identified implicating the gene in circadian-related, guanosine-mediated signaling. The transcription transactivator protein, CBP/p300-interacting transactivators with glutamic acid/aspartic acid-rich carboxyl-terminal domain, which had not been previously identified in brain, was enriched in suprachiasmatic nucleus and discrete regions of the hypothalamus and forebrain. The potential regulatory role of CBP/p300-interacting transactivators with glutamic acid/aspartic acid-rich carboxyl-terminal domain in the transcription of genes like TGF-alpha implicates the protein in diurnal activity rhythms. These results demonstrate the ability of gene expression profiling to identify potential candidates important in circadian or homeostatic processes.


Subject(s)
Carrier Proteins/metabolism , Circadian Rhythm/physiology , Fatty Acid-Binding Proteins/metabolism , GTP Phosphohydrolases/metabolism , Gene Expression Regulation/physiology , Hypothalamus/metabolism , Immediate-Early Proteins/metabolism , Repressor Proteins/metabolism , Animals , Blotting, Northern/methods , In Situ Hybridization/methods , Male , Mice , Mice, Inbred C57BL , Oligonucleotide Array Sequence Analysis/methods
13.
Cancer Res ; 57(18): 4098-104, 1997 Sep 15.
Article in English | MEDLINE | ID: mdl-9307299

ABSTRACT

We examined the expression of glial- and neuronal-specific mRNAs within human gliomas using in situ hybridization. We found that low-grade astrocytomas contained a high number of proteolipid protein (PLP) mRNA-positive cells and that the number of PLP-stained cells decreased markedly with increasing tumor grade. Interestingly, the ratio of PLP mRNA-stained cells:myelin basic protein (MBP) mRNA-stained cells in normal white matter and low-grade astrocytoma was about 2:1 but approached 1:1 with increasing tumor grade. This parameter appeared to be a good indicator of tumor infiltration in astrocytomas, so we tested this in the analysis of other gliomas. Unlike astrocytomas, oligodendrogliomas were found consistently to contain few PLP mRNA- or MBP mRNA-expressing cells. In contrast, gemistocytic astrocytomas, typically highly invasive tumors, contained high numbers of PLP-positive cells and a ratio of PLP mRNA:MBP mRNA-stained cells of about 1.5:1, similar to low-grade astrocytomas. Nonradioactive in situ hybridization also enabled the morphological identification of specific cells. For example, gemistocytic astrocytes, which were found to be strongly vimentin mRNA positive, contained little glial fibrillary acidic protein mRNA and did not stain for PLP or MBP mRNAs. Neuronal mRNAs, such as neurofilament 68, were observed in small numbers of entrapped neurons within gliomas but were uninformative with respect to predicting tumor grade. Our results suggest that oligodendrocytes survive low-grade tumor infiltration and that glial tumor cells, unlike cell lines derived from them, do not express oligodendrocyte or neuronal mRNAs. In addition, the expression of mRNAs for the two major myelin protein genes, PLP and MBP, could be used to predict the grade and extent of tumor infiltration in astrocytomas.


Subject(s)
Astrocytoma/genetics , Brain Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Glioma/genetics , Neuroglia/physiology , Oligodendroglia/physiology , Glial Fibrillary Acidic Protein/genetics , Humans , In Situ Hybridization , Keratins/genetics , Myelin Basic Protein/genetics , Myelin Proteolipid Protein/genetics , Neurofilament Proteins/genetics , Neurons/physiology , Oligodendroglioma/genetics , RNA, Messenger/genetics , RNA, Neoplasm/genetics , Vimentin/genetics
14.
J Neurosci ; 22(20): 8981-91, 2002 Oct 15.
Article in English | MEDLINE | ID: mdl-12388605

ABSTRACT

Transgenic mice were generated to permit the targeted ablation of cortical preplate cells at the time they are born. In these mice, the 1.3 kb golli promoter of the myelin basic protein gene was used to drive the herpes simplex virus thymidine kinase (TK) transgene in cortical preplate cells. Heterozygous transgenic pairs were bred, and pregnant dams were treated with ganciclovir at embryonic days 11-12 to ablate preplate cells at the time the preplate was forming. This paradigm exposed control (TK-) and experimental (TK+) littermates to exactly the same conditions. Embryological ablation of preplate cells led to an early disruption of the radial glial framework and subplate structure in the developing cortex and dramatically altered the cellular lamination and connectivity of the cortical plate. The disturbed radial glial network contributed to an impaired radial migration of neurons into the cortical plate from the ventricular zone. The cortical plate became dyslaminated, and there was a substantial reduction in short- and long-range cortical projections within the cortex and to subcortical regions. Cell death within the cortical plate and the proliferative zones was substantially increased in the ablated animals. After birth, a cortical lesion developed, which became exacerbated with the secondary onset of hydrocephaly in the second postnatal week. The results underscore the critical importance of the preplate in cortex formation, mediated through its guidance of the formation of radial glial scaffolding, subsequent neuronal migration into the incipient cortical plate, and the final arrangement of its vertical organization and cellular connectivity.


Subject(s)
Cerebral Cortex/embryology , Embryonic Structures/embryology , Neurons/drug effects , Animals , Bromodeoxyuridine , Cell Death/drug effects , Cell Death/genetics , Cell Movement/drug effects , Cerebral Cortex/cytology , Cerebral Cortex/drug effects , Embryonic Structures/cytology , Embryonic Structures/drug effects , Ganciclovir/pharmacology , Hydrocephalus/chemically induced , Hydrocephalus/genetics , Hydrocephalus/pathology , Immunohistochemistry , In Situ Nick-End Labeling , Mice , Mice, Transgenic , Models, Animal , Myelin Basic Protein/genetics , Nervous System Malformations/chemically induced , Nervous System Malformations/genetics , Nervous System Malformations/pathology , Neuroglia/cytology , Neuroglia/drug effects , Neurons/cytology , Promoter Regions, Genetic/genetics , Simplexvirus/genetics , Thymidine Kinase/biosynthesis , Thymidine Kinase/genetics
15.
Neuroscience ; 135(1): 285-97, 2005.
Article in English | MEDLINE | ID: mdl-16084664

ABSTRACT

Relatively little attention has been focused on mechanisms related to neural plasticity and drug abuse in adolescence, compared with abundant research using adult animal models. As smoking is typically initiated in adolescence, an important question to address is whether the adolescent brain responds differently to nicotine compared with the adult. To investigate this question, we examined the expression of a number of early response genes (arc, c-fos and NGFI-B) that have been implicated in synaptic plasticity and addiction, following acute nicotine in adolescent and adult rats. Baseline expression of arc and c-fos was higher in adolescent brains compared with adults. Following acute nicotine treatment (0.1, 0.4mg/kg), we found a marked induction of arc mRNA in the prefrontal cortex of nicotine-treated adolescents compared with a less pronounced increase of arc in the adult. c-fos and NGFI-B were also upregulated by nicotine, but not in an age-related manner. In contrast, nicotine induced less arc, c-fos, and NGFI-B expression in the somatosensory cortex of adolescents compared with adults. A fourth gene, quinoid dihydropteridine reductase was expressed at lower levels in white matter of the adolescent forebrain compared with the adult, but was not affected by nicotine. These results suggest that in adolescence, the activity of specific early response genes is higher in brain regions critical for emotional regulation and decision-making. Further, nicotine affects key plasticity molecules in these areas in a manner different from the adult. Thus, adolescence may represent a neurobiologically vulnerable period with regard to nicotine exposure.


Subject(s)
Immediate-Early Proteins/biosynthesis , Nerve Tissue Proteins/biosynthesis , Neuronal Plasticity/genetics , Nicotine/pharmacology , Prosencephalon/physiology , RNA, Messenger/biosynthesis , Aging/physiology , Animals , Cytoskeletal Proteins , DNA Primers , In Situ Hybridization , Male , Prefrontal Cortex/physiology , Prosencephalon/drug effects , Rats , Rats, Sprague-Dawley , Synapses/physiology , Up-Regulation/genetics
16.
Mech Dev ; 87(1-2): 207-12, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10495289

ABSTRACT

We characterized the first POU-homeoprotein in a crustacean (designated APH-1 for Artemia POU-Homeoprotein, EMBL Y15070). The amino acid sequence of the APH-1 POU-domain is identical, except for two residues, to that of the two class III POU proteins Cf1-a (Drosophila) and POU-M1 (Bombyx mori). Southern blot analysis suggests that crustaceans have only one class III POU gene. RT-PCR and whole-mount in situ hybridization show that APH-1 mRNA is present in larvae specifically in the salt gland, an organ which is involved in osmoregulation, and disappears in the adult.


Subject(s)
Artemia/genetics , Caenorhabditis elegans Proteins , Gene Expression , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Salt Gland/metabolism , Amino Acid Sequence , Animals , Artemia/metabolism , Base Sequence , Blotting, Southern , DNA Restriction Enzymes/metabolism , In Situ Hybridization , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Time Factors
17.
J Comp Neurol ; 391(1): 87-98, 1998 Feb 02.
Article in English | MEDLINE | ID: mdl-9527544

ABSTRACT

The cellular localization of the dopaminergic D2 receptor (D2R) mRNA and protein was determined during postnatal development, from birth to 35 days, in the rat neostriatum by in situ hybridization histochemistry and immunohistochemistry. To localize and identify more precisely the morphology of cells expressing the D2R mRNA, nonradioactive, digoxigenin in situ hybridization was performed. Throughout this period of development, D2R mRNA and protein were widely expressed by neostriatal cells, adjoining forebrain cells and small cellular processes. Within morphologically identifiable neurons, the expression of the D2 receptor appeared to occur after cell division ceased. D2R gene expression appeared during neuronal migration and followed the developmental pattern of neuronal settling within the neostriatum. Both D2R mRNA and protein appeared to colocalize in neostriatal cells and the labeling of both appeared to accumulate within the cells progressively with age. The structural phenotypes of neostriatal neurons bearing D2R mRNA and protein were diverse throughout postnatal development. The most frequently stained cells were a heterogeneous group of medium spiny and aspiny neurons. Large cells corresponding to aspiny neurons were less frequently stained. Both phenotypes exhibited considerable postnatal growth of their cell bodies. In addition to neurons, other cell types were also observed to express the D2R mRNA and protein over the developmental period studied. These other cells included patches of ciliated ependymal cells lining the lateral ventricles and many interfascicular oligodendroglia of forebrain fiber tracts. These results demonstrate the unexpected expression of the dopaminergic D2 receptor in non-neuronal cells within the brain. They provide a novel morphologic suggestion that the dopaminergic D2 receptor may support unrecognized, nonsynaptic functions in specific non-neuronal cell populations in the nervous system.


Subject(s)
Neostriatum/chemistry , Prosencephalon/chemistry , Receptors, Dopamine D2/genetics , Animals , Ependyma/cytology , Ependyma/metabolism , Female , Histocytochemistry , Immunohistochemistry , In Situ Hybridization , Male , Morphogenesis , Neostriatum/embryology , Neostriatum/growth & development , Neurons/metabolism , Oligodendroglia/metabolism , Prosencephalon/embryology , Prosencephalon/growth & development , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley
18.
J Comp Neurol ; 374(3): 342-53, 1996 Oct 21.
Article in English | MEDLINE | ID: mdl-8906503

ABSTRACT

The myelin basic protein (MBP) gene locus is composed of two overlapping transcription units that share all of the MBP exons. One of these transcription units expresses the MBPs and the other expresses a family of proteins structurally related to the MBPs. This second transcription unit is called the Golli gene, and the entire complex is called the Golli-mbp gene. In this study, the expression of the Golli gene was examined in the human fetal central nervous system (CNS). By using reverse transcriptase-polymerase chain reaction cloning we have identified eight new members of the Golli gene family of transcripts expressed in the human CNS. Golli gene expression was examined by in situ hybridization and immunohistochemistry, and surprisingly, Golli products were found to be expressed in neurons as well as oligodendrocytes. Furthermore, the subcellular distribution of Golli immunoreactivity in fetal spinal cord interneurons shifted between the various laminae. Golli protein was localized within the nuclei of interneurons in the posterior horn, but was found in the cell bodies and processes of interneurons in the anterior horn. Within oligodendrocytes, Golli protein was detected in the cell bodies and processes, including processes which were wrapping axonal segments. Golli mRNA expression was also observed in neurons within the cerebral cortex between 18 and 20 weeks postconception, prior to myelination of this brain region. During this period, there was a striking developmental increase in the numbers and in the locations of neurons expressing Golli mRNAs within the cortical plate. The diverse distribution of Golli proteins within neurons and oligodendrocytes indicates that their function is quite different from that of the MBPs to which they are closely related.


Subject(s)
Central Nervous System/embryology , Gene Expression Regulation, Developmental/physiology , Myelin Basic Protein/biosynthesis , Myelin Basic Protein/genetics , Neurons/physiology , Oligodendroglia/physiology , Antibodies/analysis , Blotting, Northern , Central Nervous System/cytology , Central Nervous System/physiology , Cerebral Cortex/cytology , Cerebral Cortex/embryology , Cerebral Cortex/physiology , Chromatography, Affinity , DNA Probes , Female , Humans , Immunohistochemistry , In Situ Hybridization , Polymerase Chain Reaction , Pregnancy , RNA, Messenger/biosynthesis , Recombinant Proteins/biosynthesis
19.
Proc Biol Sci ; 268(1473): 1279-85, 2001 Jun 22.
Article in English | MEDLINE | ID: mdl-11410155

ABSTRACT

According to the theory of mate choice based on heterozygosity, mates should choose each other in order to increase the heterozygosity of their offspring. In this study, we tested the 'good genes as heterozygosity' hypothesis of mate choice by documenting the mating patterns of wild Atlantic salmon (Salmo salar) using both major histocompatibility complex (MHC) and microsatellite loci. Specifically, we tested the null hypotheses that mate choice in Atlantic salmon is not dependent on the relatedness between potential partners or on the MHC similarity between mates. Three parameters were assessed: (i) the number of shared alleles between partners (x and y) at the MHC (M(xy)), (ii) the MHC amino-acid genotypic distance between mates' genotypes (AA(xy)), and (iii) genetic relatedness between mates (r(xy)). We found that Atlantic salmon choose their mates in order to increase the heterozygosity of their offspring at the MHC and, more specifically, at the peptide-binding region, presumably in order to provide them with better defence against parasites and pathogens. This was supported by a significant difference between the observed and expected AA(xy) (p = 0.0486). Furthermore, mate choice was not a mechanism of overall inbreeding avoidance as genetic relatedness supported a random mating scheme (p = 0.445). This study provides the first evidence that MHC genes influence mate choice in fish.


Subject(s)
Major Histocompatibility Complex , Salmo salar/genetics , Salmo salar/immunology , Sexual Behavior, Animal , Alleles , Animals , Female , Heterozygote , Inbreeding , Male , Microsatellite Repeats , Models, Biological , Polymorphism, Genetic , Salmo salar/physiology
20.
Proc Biol Sci ; 270(1526): 1839-47, 2003 Sep 07.
Article in English | MEDLINE | ID: mdl-12964987

ABSTRACT

The rich species diversity of the marine Indo-West Pacific (IWP) has been explained largely on the basis of historical observation of large-scale diversity gradients. Careful study of divergence among closely related species can reveal important new information about the pace and mechanisms of their formation, and can illuminate the genesis of biogeographic patterns. Young species inhabiting the IWP include urchins of the genus Echinometra, which diverged over the past 1-5 Myr. Here, we report the most recent divergence of two cryptic species of Echinometra inhabiting this region. Mitochondrial cytochrome oxidase 1 (CO1) sequence data show that in Echinometra oblonga, species-level divergence in sperm morphology, gamete recognition proteins and gamete compatibility arose between central and western Pacific populations in the past 250 000 years. Divergence in sperm attachment proteins suggests rapid evolution of the fertilization system. Divergence of sperm morphology may be a common feature of free-spawning animals, and offers opportunities to simultaneously understand genetic divergence, changes in protein expression patterns and morphological evolution in traits directly related to reproductive isolation.


Subject(s)
Phylogeny , Sea Urchins/anatomy & histology , Sea Urchins/genetics , Spermatozoa/ultrastructure , Animals , Base Sequence , Cluster Analysis , DNA, Mitochondrial/genetics , Fertility , Geography , Indian Ocean , Male , Molecular Sequence Data , Pacific Ocean
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