Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Subpopulations

  • b cell subpopulation
  • cell subpopulation
  • different subpopulation
  • discrete subpopulation
  • distinct subpopulation
  • lymphocyte subpopulation
  • macrophage subpopulation
  • neuronal subpopulation
  • novel subpopulation
  • other subpopulation
  • separate subpopulation
  • small subpopulation
  • specific subpopulation
  • sperm subpopulation

  • Selected Abstracts

    ORIGINAL ARTICLE: The Characterization of the Subpopulation of Suppressive B7H4+ Macrophages and the Subpopulation of CD25+ CD4+ and FOXP3+ Regulatory T-cells in Decidua during the Secretory Cycle Phase, Arias Stella Reaction, and Spontaneous Abortion , A Preliminary Report

    Lukasz Wicherek
    Problem, The presence of immunosuppressive cells within the endometrium and decidua is crucial for establishing maternal immune tolerance against fetal antigens. We decided to evaluate the subpopulations of Treg cells and B7H4 macrophages in eutopic endometrium typified by Arias Stella reaction during the development of Fallopian tube pregnancy as well as in decidua at the time of spontaneous abortion (SA), and to compare these findings to those observed in the endometrium during the secretory cycle phase of healthy women. Method of study, The decidual tissue samples evaluated in our study were obtained from 26 women who underwent curettage as a result of the following circumstances: five of the women because of a laparoscopic procedure necessitated by Fallopian tube pregnancy, and 11 of them because of SA. The control group consisted of 10 patients on whom curettage was preformed as an additional procedure during laparoscopic myomectomy. The presence of regulatory T-cells and B7H4-positive macrophages in the samples was analysed by fluorescence-activated cell sorter (FACScan). Results, Both the percentages of FOXP3+ cells in the subpopulation of CD25+ CD4+ T lymphocytes and the percentage of B7H4-positive cells in the macrophage subpopulation found in the deciduae of patients suffering SA were higher than those found in eutopic endometrium with Arias Stella reaction. No such differences in the percentages of these cells were observed when the tissue samples from patients with SA were compared with those from the control group. The percentage of B7H4-positive macrophages, however, was found to be significantly lower in endometrium with Arias Stella reaction in comparison to that observed in secretory endometrium. Conclusion, The alterations in both the Treg cell and suppressive B7H4+ macrophage subpopulations would seem to be related to the suppression of maternal immune cells in the endometrium at the beginning of decidualization. [source]

    ORIGINAL ARTICLE: Changes in the Subpopulation of CD25+ CD4+ and FOXP3+ Regulatory T Cells in Decidua with Respect to the Progression of Labor at Term and the Lack of Analogical Changes in the Subpopulation of Suppressive B7-H4+ Macrophages , A Preliminary Report

    Krystyna Galazka
    Problem, The initiation of labor is accompanied by alterations in the level of maternal immune tolerance toward fetal antigens. It is a complex molecular response leading to a brief activation of the maternal immune system with an accompanying capacity to restrict this same activation. The aim of our study was to evaluate the subpopulation of regulatory T cells (Tregs) and B7-H4 macrophages in the decidua basalis during cesarean sections performed on patients in various stages of labor. Method of study, The decidual tissue samples evaluated in our study were obtained from 23 pregnant women who underwent cesarean sections at term. Moreover, the patients were divided into three subgroups according to the progression of labor at the time of the cesarean. The presence of Treg cells and B7-H4 positive macrophages were analysed by fluorescence-activated cell sorter. Results, The percentages of FOXP3+ cells in the subpopulation of CD25+ CD4+ T lymphocytes found in the deciduas of patients decreased with the successive stages of labor, while the percentages of B7-H4 positive cells in the macrophage subpopulation remained almost constant. Conclusion, These changes in the Treg cell subpopulation in the decidua would seem to be related to a brief activation of the maternal immune system as labor begins and lack of analogical changes in the subpopulation of decidual suppressive B7-H4+ macrophages that enable the restriction of this same activation as labor progresses. [source]

    Distribution of neurotrophin-3 during the ontogeny and regeneration of the lizard (Gallotia galloti) visual system

    E. Santos
    Abstract We have previously described the spontaneous regeneration of retinal ganglion cell axons after optic nerve (ON) transection in the adult Gallotia galloti. As neurotrophin-3 (NT-3) is involved in neuronal differentiation, survival and synaptic plasticity, we performed a comparative immunohistochemical study of NT-3 during the ontogeny and regeneration (after 0.5, 1, 3, 6, 9, and 12 months postlesion) of the lizard visual system to reveal its distribution and changes during these events. For characterization of NT-3+ cells, we performed double labelings using the neuronal markers HuC-D, Pax6 and parvalbumin (Parv), the microglial marker tomato lectin or Lycopersicon esculentum agglutinin (LEA), and the astroglial markers vimentin (Vim) and glial fibrillary acidic protein (GFAP). Subpopulations of retinal and tectal neurons were NT-3+ from early embryonic stages to adulthood. Nerve fibers within the retinal nerve fiber layer, both plexiform layers and the retinorecipient layers in the optic tectum (OT) were also stained. In addition, NT-3+/GFAP+ and NT-3+/Vim+ astrocytes were detected in the ON, chiasm and optic tract in postnatal and adult lizards. At 1 month postlesion, abundant NT-3+/GFAP+ astrocytes and NT-3,/LEA+ microglia/macrophages were stained in the lesioned ON, whereas NT-3 became downregulated in the experimental retina and OT. Interestingly, at 9 and 12 months postlesion, the staining in the experimental retina resembled that in control animals, whereas bundles of putative regrown fibers showed a disorganized staining pattern in the OT. Altogether, we demonstrate that NT-3 is widely distributed in the lizard visual system and its changes after ON transection might be permissive for the successful axonal regrowth. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008 [source]

    Subpopulations of Cryptocephalus beetles (Coleoptera: Chrysomelidae): geographically close but genetically far

    R. W. Piper
    Abstract. The leaf beetles Cryptocephalus coryli, C. decemmaculatus and C. nitidulus are of conservation concern and are included on the UK Biodiversity Action Plan. The distinctiveness of the disjunct remaining populations of these beetles was compared to that of more continuously distributed Cryptocephalus species. This was carried out with a view to defining evolutionary significant units (ESUs) in the rare species. A portion of the cytochrome b gene, an intergenic spacer and partial tRNA was analysed from 93 specimens of Cryptocephalus beetle (Coleoptera: Chrysomelidae). Considerable sequence divergence was apparent in all the species, even at an intersite scale when the distances between sampled localities were very small (< 1 km). Intrapopulation, intersite and interpopulation divergence observed in the rare species was reflected in the species that have a more continuous distribution, implying that dispersal ability in these species is poor and gene flow can be impeded by relatively trivial barriers to dispersal. The evidence suggests that the disjunct populations of the rare Cryptocephalus species can, tentatively, be considered as ESUs. This has important implications for management strategies and reintroductions. [source]

    Audiogenic kindling in Wistar and WAG/Rij rats: Kindling-prone and kindling-resistant subpopulations

    EPILEPSIA, Issue 10 2008
    Lyudmila V. Vinogradova
    Summary Purpose:, Audiogenic kindling (AK) is a model of naturally occurring epileptogenesis triggered by repeated sound stimulation of rats genetically prone to audiogenic seizures. It is accepted that limbic seizure networks underlie progressive changes in behavioral seizure pattern during AK. The present study investigated AK progression in rats susceptible and unsusceptible to absence seizures. Methods:, Progression of AK as indicated by an appearance and intensification of limbic clonus was examined in Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats with genetic absence epilepsy and in Wistar rats. Results:, Subpopulations of kindling-prone and kindling-resistant rats were found in both Wistar and WAG/Rij strains. Despite identical seizure responses to the first sound stimulation, AK progression dramatically differed between the two subpopulations. AK-prone rats exhibited rapid kindling development up to maximal stage-5 severity. In AK-resistant rats, limbic clonus did not appear after 30 stimulations or if it appeared, it did not progress beyond stage 2. The proportions of AK-prone and AK-resistant animals within Wistar and WAG/Rij strains were similar. Comparison of Wistar and WAG/Rij rats within the kindling-prone and kindling-resistant groups did not reveal a significant strain effect on AK progression. However, within the WAG/Rij strain, a significantly higher incidence of absence seizures was found in AK-resistant rats compared to AK-prone rats. Conclusions:, The present study demonstrates that sensitivity to sound-induced epileptogenesis differs dramatically within Wistar and WAG/Rij strains, whereas genetic susceptibility to absence seizures does not change AK progression significantly. It is supposed that an increased incidence of nonconvulsive seizures and resistance to kindling result from a common seizure modulating mechanism. [source]

    Effect of First Treatment with Aminobisphosphonates Pamidronate and Ibandronate on Circulating Lymphocyte Subpopulations

    Martin Pecherstorfer
    Abstract Up to 60% of patients receiving their first infusion of the bisphosphonate pamidronate experience an acute-phase reaction. In this study, we used flow cytometry to determine the effects of pamidronate treatment on circulating lymphocyte subpopulations, and we investigated whether pamidronate and ibandronate treatment affect lymphocyte subpopulations differently. Twenty patients received a pamidronate infusion, 20 patients received intravenously injected ibandronate, and 10 controls received a clodronate infusion. Pamidronate treatment was followed by a significant increase in median body temperature at the 10-hour measurement and a significant decrease in counts of circulating lymphocytes, natural killer cells, T cells, and CD4+ and CD8+ T-cell subsets. Ibandronate treatment did not affect median body temperature, and it was associated at the 10-hour measurement with maximum increases in total lymphocyte count, B cells, T cells, and CD4+ and CD8+ T-cell subsets. Thus, there is a substantial difference in the hematologic response to initial treatments with pamidronate and ibandronate. Clodronate treatment did not induce changes in body temperature or significantly affect the number of circulating T cells and NK cells. The reduction in lymphocyte subsets after initial pamidronate therapy might be mediated by the release of tumor necrosis factor ,, whose source in the acute-phase reaction could be T cells. [source]

    Relatedness of Macrophomina phaseolina isolates from tallgrass prairie, maize, soybean and sorghum

    MOLECULAR ECOLOGY, Issue 1 2010
    A. A. SALEH
    Abstract Agricultural and wild ecosystems may interact through shared pathogens such as Macrophomina phaseolina, a generalist clonal fungus with more than 284 plant hosts that is likely to become more important under climate change scenarios of increased heat and drought stress. To evaluate the degree of subdivision in populations of M. phaseolina in Kansas agriculture and wildlands, we compared 143 isolates from maize fields adjacent to tallgrass prairie, nearby sorghum fields, widely dispersed soybean fields and isolates from eight plant species in tallgrass prairie. Isolate growth phenotypes were evaluated on a medium containing chlorate. Genetic characteristics were analysed based on amplified fragment length polymorphisms and the sequence of the rDNA-internal transcribed spacer (ITS) region. The average genetic similarity was 58% among isolates in the tallgrass prairie, 71% in the maize fields, 75% in the sorghum fields and 80% in the dispersed soybean fields. The isolates were divided into four clusters: one containing most of the isolates from maize and soybean, two others containing isolates from wild plants and sorghum, and a fourth containing a single isolate recovered from Solidago canadensis in the tallgrass prairie. Most of the sorghum isolates had the dense phenotype on media containing chlorate, while those from other hosts had either feathery or restricted phenotypes. These results suggest that the tallgrass prairie supports a more diverse population of M. phaseolina per area than do any of the crop species. Subpopulations show incomplete specialization by host. These results also suggest that inoculum produced in agriculture may influence tallgrass prairie communities, and conversely that different pathogen subpopulations in tallgrass prairie can interact there to generate ,hybrids' with novel genetic profiles and pathogenic capabilities. [source]

    Blood Lymphocyte Subpopulations, Neutrophil Phagocytosis and Proteinogram During Late Pregnancy and Postpartum in Mares

    R Agrícola
    Contents The aim of this study was to evaluate peripheral blood lymphocyte subpopulations, neutrophil phagocytic capacity and proteinogram characteristics in mares, during the last trimester of pregnancy and in postpartum. Measurement of phagocytosis and quantification of T-lymphocyte subsets were done by flow cytometry. Quantification of T-lymphocyte subsets was performed with monoclonal antibodies specific for CD2, CD3, CD4 and CD8 cell markers. Natural killer and B-cell counts were estimated mathematically. Serum proteinogram was obtained by electrophoresis. No significant differences were observed between gestation and postpartum on CD4+, CD8+ and NK+ lymphocyte subsets, CD4 : CD8 ratio and phagocytosis. The percentage of cells expressing CD3 (64.2 ± 1.8) and CD2 (68.4 ± 1.7) (Mean ± SEM) was reduced during gestation vs postpartum (69.7 ± 1.5 and 73.8 ± 1.4 respectively) (p < 0.05). During pregnancy, CD19+ (31.6 ± 1.7) was higher than in postpartum (26.2 ± 1.4) (p < 0.05). Total T cells (2911 ± 227 cells/,l), T helper cells (2144 ± 169 cells/,l) and T-cytotoxic cells (767 ± 68 cells/,l) were depressed in pregnancy, when compared with postpartum (4093 ± 337 cells/,l; 3004 ± 276 cells/,l; 1089 ± 94 cells/,l respectively) (p < 0.01). Total white blood cell count was reduced during pregnancy (8815 ± 427 cells/,l) with respect to postpartum (10742 ± 446 cells/,l) (p < 0.01), while neutrophil count did not change. Total proteins, albumin, ,1,,2,,1, ,2, , globulins and albumin : globulin did not differ. Our results suggest that the physiological immune depression occurring in mares, during gestation might be due to T-helper and T-cytotoxic lymphocytes reduction. [source]

    Effects of Cryopreservation on Bull Spermatozoa Distribution in Morphometrically Distinct Subpopulations

    J Rubio-Guillén
    Contents Assisted sperm morphometry analysis (ASMA) was used in this study to determine the effects of cryopreservation on bull spermatozoa distribution in morphometrically distinct subpopulations. Ejaculates were collected from five bulls and were divided. One portion was diluted at 30°C in a skim milk,egg yolk medium, containing glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for a minimum of 200 sperm heads were analysed from each sample by means of the Sperm-Class Analyser® (SCA), and the mean measurements recorded. Our results showed that applying the ASMA technology and multivariate cluster analyses, it was possible to determine that three separate subpopulations of spermatozoa with different morphometric characteristics coexist in bull ejaculates (large, average and small spermatozoa). The mean values of each sperm head dimension among the three subpopulations of spermatozoa were significantly different (p < 0.001). Besides, there were significant (p < 0.001) differences in the distribution of these three sperm subpopulations between fresh and thawed samples. Thus, the percentage of representation of the subpopulation that includes those spermatozoa whose dimensions are the biggest, decreased from 52.06% in extended fresh samples to 15.51% in the thawed ones. Contrarily, the percent of representation of the subpopulation containing the smallest spermatozoa, increased from 8.70% in extended fresh samples to 34.04% in the thawed ones. In conclusion, the present study confirms the heterogeneity of sperm head dimensions in bull semen, heterogeneity that vary through the cryopreservation procedure. [source]

    Multivariate Cluster Analysis Regression Procedures as Tools to Identify Motile Sperm Subpopulations in Rabbit Semen and to Predict Semen Fertility and Litter Size

    A Quintero-Moreno
    Contents Computerized motility analysis (CASA) shows that four separate subpopulations of spermatozoa with different motility characteristics co-exist in rabbit ejaculates. There were significant (p < 0.01) differences in the distribution of these subpopulations among separate genetic lines, total sperm abnormalities and the percentage of altered acrosomes. Furthermore, logistic and linear multivariate regressions among several parameters of rabbit semen quality analysis were tested for use as predictive tools for the fertilizing ability of a specific artificial insemination semen sample. Logistic regression analysis rendered two mathematical, significant (p < 0.01) models: one between sperm viability and conception rate and the other between total sperm abnormalities and conception rate. Multiple linear regression analyses also yielded some significant relationships between both fertility (p < 0.001) and litter size (p < 0.05), with respect to some semen characteristics. Our results support the hypothesis that the predictive in vivo fertility use of the standard rabbit semen quality analysis coupled with a CASA determination could be reasonably achieved by applying linear and logistic regression analyses among several parameters of rabbit semen quality analysis. [source]

    Total and Differential Leucocyte Counts and Lymphocyte Subpopulations in Lymph, Afferent and Efferent to the Supramammary Lymph Node, During Endotoxin-Induced Bovine Mastitis

    S Lun
    Contents Leucocyte trafficking in afferent and efferent mammary lymph and the supramammary lymph node in cows was examined during 4 h after intramammary infusion of endotoxin from Escherichia coli. Total and differential leucocyte counts were measured in milk, blood and lymph. The proportions of CD4+, CD8+, major histocompatibility complex (MHC) class II+ and IgM+ lymphocytes were examined in the lymph and lymph node. At post-infusion hour (PIH) 4, the flow rates of both lymph fluids had increased approximately eightfold. Total leucocyte concentration increased in afferent lymph, but decreased in efferent lymph. Neutrophils increased in afferent lymph at PIH 2 and in efferent lymph and milk at PIH 4. The predominant cell type in afferent lymph shifted from lymphocyte to neutrophil while lymphocyte was still at PIH 4 the predominant type in efferent lymph. Among the lymphocytes, B cells were predominant in afferent lymph and lymph node at PIH 4 while T cells, mainly CD4+ cells, were predominant in efferent lymph both at PIH 0 and PIH 4. The CD4 : CD8 ratio was higher in efferent lymph and the challenged lymph node than in afferent lymph and the control node, respectively. There was a significant difference in proportions of each lymphocyte subpopulation except for IgM+ cells, between afferent and efferent lymph after infusion. According to the results, there was already during the first hours of the immune response, a non-random trafficking of neutrophils and lymphocyte subpopulations resulting in a changed distribution of cells in afferent and efferent lymph and a difference in lymphocyte reactivity between the two lymph fluids. [source]

    Intracellular calcium regulation among subpopulations of rat dorsal root ganglion neurons

    Shao-Gang Lu
    Primary afferent neurons are functionally heterogeneous. To determine whether this functional heterogeneity reflects, in part, heterogeneity in the regulation of the concentration of intracellular Ca2+ ([Ca2+]i), the magnitude and decay of evoked Ca2+ transients were assessed in subpopulations of dorsal root ganglion (DRG) neurons with voltage clamp and fura-2 ratiometric imaging. To determine whether differences in evoked Ca2+ transients among subpopulations of DRG neurons reflected differences in the contribution of Ca2+ regulatory mechanisms, pharmacological techniques were employed to assess the contribution of influx, efflux, release and uptake pathways. Subpopulations of DRG neurons were defined by cell body size, binding of the plant lectin IB4 and responsiveness to the algogenic compound capsaicin (CAP). Ca2+ transients were evoked with 30 mm K+ or voltage steps to 0 mV. There were marked differences between subpopulations of neurons with respect to both the magnitude and decay of the Ca2+ transient, with the largest and most slowly decaying Ca2+ transients in small-diameter, IB4 -positive, CAP-responsive neurons. The smallest and most rapidly decaying transients were in large-diameter, IB4 -negative and CAP-unresponsive DRG neurons. These differences were not due to a differential distribution of voltage-gated Ca2+ currents. However, these differences did appear to reflect a differential contribution of other influx, efflux, release and uptake mechanisms between subpopulations of neurons. These results suggest that electrical activity in subpopulations of DRG neurons will have a differential influence on Ca2+ -regulated phenomena such as spike adaptation, transmitter release and gene transcription. Significantly more activity should be required in large-diameter non-nociceptive afferents than in small-diameter nociceptive afferents to have a comparable influence on these processes. [source]

    ORIGINAL ARTICLE: Abnormal Pattern of Lymphocyte Subpopulations in the Endometrium of Infertile Women with Chronic Endometritis

    Maria Matteo
    Problem, Endometrial lymphocytes play a critical role in endometrial receptivity. This study aimed at evaluating the variations induced by chronic endometritis (CE) on endometrial lymphocyte subsets. We compared the results in infertile women diagnosed with CE with those in unexplained infertile women without any sign of CE. Method of study, Twenty-three women referring for unexplained infertility had hysteroscopy and endometrial biopsy in the follicular phase; in nine women, CE was diagnosed (group CE+), while in 14 it was not (group CE,). All patients in the late secretory phase of the subsequent cycle underwent endometrial biopsy. By flow cytometry, the percentage and phenotype of the endometrial lymphocyte subpopulations were analyzed. Results, The secretory endometrium of patients with CE displayed significantly lower percentage of CD56+ CD16, and of CD56bright CD16, cells (47.8% ± 18.6 and 30.1% ± 20.5 versus 79.5% ± 3.9 and 67.3% ± 8.1, respectively; P < 0.01) as compared with group CE(,), while the percentage of CD3+ cells was significantly higher (25% ± 12.2 versus 10.5 ± 5; P < 0.01). Conclusion, Infertile women with CE showed an abnormal percentage of endometrial lymphocyte subsets compared with unexplained infertile women suggesting that different mechanisms underlie the adverse pregnancy outcome of the two groups of patients. [source]

    Maternal and Neonatal Lymphocyte Subpopulations at Delivery and 3 Days Postpartum: Increased Coexpression of CD45 Isoforms

    Emilia Juretic
    Problem:, Huge physiologic changes during parturition involve immune cells. Alterations in maternal and neonatal lymphocytes postpartum might ascertain the subpopulations that are most affected and may possibly be of importance in the process. Method of study:, Peripheral blood was taken from 20 healthy women at vaginal delivery and 3 days later, concomitantly with cord and peripheral blood from their newborns. Lymphocyte immunophenotyping was done by three-color flow-cytometry. Results:, Maternal T helper cells were decreased and natural killer (NK) cells were significantly increased during labor. Percentage of CD4+ and percentage and absolute count of CD8+ cells coexpressing CD45RA and CD45RO antigens were higher than 3 days later. In cord blood NK cells were considerably increased and more CD4+ cells expressed CD45RO antigen. Conclusion:, Coexpression of CD45RA and CD45RO molecules indicates activation of maternal CD4+ and CD8+ lymphocytes. NK cells increase suggests their possible association with parturition processes. Lymphocyte subsets in cord blood correspond to maternal subsets to some extent. [source]

    Rabbit Facial Nerve Regeneration in Autologous Nerve Grafts After Antecedent Injury ,

    THE LARYNGOSCOPE, Issue 4 2000
    FACS, J. Gershon Spector MD
    Objective The effect of incomplete antecedent injuries on subsequent facial nerve regeneration within cable graft repairs is not known. The purpose of this study is to compare facial nerve regeneration after an immediate and delayed neural cable graft repair. Method Rabbit facial nerve regeneration after complete transectional injuries of the buccal division was compared in two experimental models. In one, a 10-mm segment of the nerve was transected, rotated 180°, and immediately repaired as a cable graft (N=8). In the second, a preliminary nerve crush was allowed to recover over a 4-week period and a 10-mm segment of nerve centered on the crush site was then transected, rotated 180°, and delay repaired as a cable graft (N = 7). Data are presented as total numbers of regenerating myelinated axons that traverse the surgical repair to innervate the cable graft and distal nerve stumps, as well as the percentage of regenerating neurites compared with preoperative pooled and individual controls. Subpopulations of regenerating neurons are delineated to quantify the pattern of neural innervation. Results Five weeks after cable graft repair both groups had similar myelinated outgrowth from the proximal nerve stump across the proximal anastomosis to innervate the cable graft (3995 ± 1209 vs. 3284 ± 651;P = .89). However, the delayed repair group had more intrafascicular regeneration within cable grafts (2261 ± 931 vs. 1660 ± 1169;P = .02) and distal nerve stump (1532 ± 281 vs. 445 ± 120;P = .004) than the immediate repair group. The immediate repair group had greater extrafascicular nerve regeneration in the cable graft (2335 ± 1954 vs. 437 ± 236;P = .001) and more myelin and axonal debris in pre-existing neural fascicles of the cable graft (P = .02) and distal nerve stump (463 ± 187 vs. 103 ± 87;P = .02). Conclusions Antecedent priming lesions do not enhance axonal survival as determined by regenerating myelinated axonal counts. However, antecedent injuries enhance the efficiency of neural innervation of the affected mimetic musculature by increasing the number of myelinated intrafascicular neural regenerants in the cable graft and distal nerve stump. This is accomplished by two factors: increased perineural fibrosis and decreased intrafascicular myelin and axonal debris. [source]

    Conserving a subpopulation of the northern Atlantic cod metapopulation with a marine protected area

    Liuming Hu
    Abstract 1.Marine reserves can play an important role in the conservation of subpopulations of marine fish metapopulations. The population spatial structure of northern Atlantic cod of Newfoundland and Labrador has characteristics of a metapopulation. Subpopulations of northern Atlantic cod on the continental shelf were decimated by decades of overfishing, and have not recovered. The remaining northern cod are concentrated in coastal areas. 2.A Marine Protected Area (MPA) was established in Gilbert Bay, Labrador by the Government of Canada in 2005 to protect the bay's resident subpopulation of northern Atlantic cod. Conservation of Gilbert Bay cod will help protect the genetic diversity of the northern cod metapopulation. 3.Unlike some other MPAs, Gilbert Bay is not a harvest refugium or ,no-take' reserve. Aboriginal subsistence fisheries for salmonids with a bycatch of cod are allowed in designated areas of the MPA. A recreational fishery for Atlantic cod by angling open to all people is under consideration. Management of the MPA must ensure that fishing activities do not endanger the local cod population. 4.The population dynamics of Gilbert Bay cod were simulated using an age-structured Leslie matrix model to estimate the total mortality under various recreational fishing scenarios. The level of sustainable harvest by a recreational fishery depends on the natural mortality of the Gilbert Bay cod population, which is unknown. Therefore, there is risk in permitting a recreational fishery in the MPA. 5.There may be benefits to the northern cod metapopulation, if the Gilbert Bay subpopulation is allowed to rebuild to the carrying capacity of the bay. If the abundance of Gilbert Bay cod exceeds the level which the local marine ecosystem can support, some cod may emigrate from the bay and recolonize adjacent coastal areas. The potential for Gilbert Bay cod to recolonize continental shelf areas is less certain. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Outcomes and Prognostic Factors of Systolic as Compared With Diastolic Heart Failure in Urban America

    Peter A. McCullough MD
    We sought to describe a large heart failure (HF) population with respect to systolic and diastolic abnormalities in terms of demographics, echocardiographic parameters, and survival. Using data abstracted from the Resource Utilization Among Congestive Heart Failure (REACH) study, a targeted subpopulation of 3471 patients had electrocardiographic, echocardiographic, and clinical data taken from automated sources during the first year of diagnosis. Among the HF population, 1811 (52.2%) had diastolic HF. Prevalence of diastolic HF trended with age, from 46.4% in those less than 45 years to 58.7% in those 85 years or older (p=0.001 for trend). Patients with diastolic HF had a higher mean ejection fraction (55.7% vs. 28.0%), lower left ventricular end-systolic diameter (3.11 vs. 4.74 cm), and lower left atrium: aortic outlet ratio (1.28 vs. 1.38) (p=0.001 for each comparison). Annualized age, sex, and race-adjusted mortality were 11.2% and 13.0% for those with diastolic and systolic HF, respectively (p=0.001). In a large, racially mixed, urban HF population, those with diastolic HF predominate and enjoy better-adjusted survival than counterparts with systolic HF. [source]

    Non-remission of depression in the general population as assessed by the HAMD-7 scale

    Andrew G. Bulloch Ph.D.
    Abstract Remission from the symptoms of depression is the optimal outcome for depression treatment. Many studies have assessed the frequency of treatment, but there are none that have estimated the frequency of treated remission in the general population. We addressed this issue in the population of Alberta using a brief Hamilton Depression Rating Scale (HAMD)-7 scale (recently validated against the HAMD-17 scale in a clinical setting) that has been proposed as a suitable indicator for remission in primary care. We used data from a survey conducted within the Alberta Depression Initiative in 2005 (n=3,345 adults), to produce a population-based estimate of the number of respondents taking antidepressant medication for depression. From this group we selected a subpopulation that did not screen positive when the MINI module for major depression was administered (i.e., who did not have an active episode). Non-remission in this subpopulation was assessed with a version of the HAMD-7 scale adapted for telephone administration by a nonclinician. Of the survey respondents, 189 reported taking antidepressant medication for depression. Of these, 115 were found not to have an active episode. However, 49.0% of this subpopulation was not in remission as evaluated by the HAMD-7. We estimate that 1.3% (95% confidence interval, 0.9,2.0%) of the population is in treated non-remission for depression. Our study indicates a substantial degree of non-remission from depression in individuals taking antidepressants in the general population. This suggests that, in addition to increasing the frequency of treatment, increasing the effectiveness of treatment can have an impact on population health. Depression and Anxiety 0:1,5, 2007. © 2007 Wiley-Liss, Inc. [source]

    Expression of the zebrafish CD133/prominin1 genes in cellular proliferation zones in the embryonic central nervous system and sensory organs

    Maura McGrail
    Abstract The CD133/prominin1 gene encodes a pentamembrane glycoprotein cell surface marker that is expressed in stem cells from neuroepithelial, hematopoietic, and various organ tissues. Here we report the analysis of two zebrafish CD133/prominin1 orthologues, prominin1a and prominin1b. The expression patterns of the zebrafish prominin1a and b genes were analyzed during embryogenesis using whole mount in situ hybridization. prominin1a and b show novel complementary and overlapping patterns of expression in proliferating zones in the developing sensory organs and central nervous system. The expression patterns suggest functional conservation of the zebrafish prominin1 genes. Initial analyses of prominin1a and b in neoplastic tissue show increased expression of both genes in a subpopulation of cells in malignant peripheral nerve sheath tumors in tp53 mutants. Based on these analyses, the zebrafish prominin1 genes will be useful markers for examining proliferating cell populations in adult organs, tissues, and tumors. Developmental Dynamics 239:1849,1857, 2010. © 2010 Wiley-Liss, Inc. [source]

    Analysis of human muscle stem cells reveals a differentiation-resistant progenitor cell population expressing Pax7 capable of self-renewal

    Bradley Pawlikowski
    Abstract Studies using mouse models have established a critical role for resident satellite stem cells in skeletal muscle development and regeneration, but little is known about this paradigm in human muscle. Here, using human muscle stem cells, we address their lineage progression, differentiation, migration, and self-renewal. Isolated human satellite cells expressed ,7-integrin and other definitive muscle markers, were highly motile on laminin substrates and could undergo efficient myotube differentiation and myofibrillogenesis. However, only a subpopulation of the myoblasts expressed Pax7 and displayed a variable lineage progression as measured by desmin and MyoD expression. Analysis identified a differentiation-resistant progenitor cell population that was Pax7+/desmin, and capable of self-renewal. This study extends our understanding of the role of Pax7 in regulating human satellite stem cell differentiation and self-renewal. Developmental Dynamics 238:138,149, 2009. © 2008 Wiley-Liss, Inc. [source]

    Nestin expression in pancreatic endocrine and exocrine cells of mice lacking glucagon signaling

    Mamdouh H. Kedees
    Abstract Nestin, a marker of neural stem cells, is also expressed by cells located in the epithelium of the pancreatic primordium and by a subpopulation of exocrine cells but not by endocrine cells. These findings raised the possibility that the pancreatic epithelium is heterogeneous and comprised of subpopulations of exocrine/nestin-positive and endocrine/nestin-negative precursor cells. We examined this issue in two mutant mouse models characterized by protracted expression of several embryonal properties in islet cells. One mutant line comprises mice lacking mature glucagon due to abrogation of proprotein convertase-2 (PC2,/,), responsible for the conversion of proglucagon into glucagon, while the second line consists of mice with a global deletion of the glucagon receptor (Gcgr,/,). We demonstrate that nestin is transiently expressed by acinar cells and by insulin and glucagon cells of islets of both lines of mice. In addition, the lack of glucagon signaling increased nestin mRNA levels in pancreas of mutant embryos and adult mice. We conclude that nestin+ cells located in the pancreatic primordium generate the cells of the endocrine and exocrine lineages. Furthermore, our results suggest that nestin expression is regulated by glucagon signaling. Developmental Dynamics 236:1126,1133, 2007. © 2007 Wiley-Liss, Inc. [source]

    Induction of neurogenin-1 expression by sonic hedgehog: Its role in development of trigeminal sensory neurons

    Mitsunori Ota
    Abstract We have examined the roles of signaling molecules in the mechanisms underlying the induction of neurogenin (ngn)-1 expression. ngn-1 is a basic helix-loop-helix (bHLH) transcription factor, which is essential for the specification of trigeminal sensory neurons. Semiquantitative reverse transcriptase-polymerase chain reaction using cranial explants in organ cultures showed that sonic hedgehog (Shh) promotes ngn-1 expression. This promoting activity was not observed in other signaling molecules examined. The promotion of ngn-1 expression by Shh, furthermore, was inhibited by cyclopamine, a specific inhibitor of Shh signaling. Shh did not affect the expression of ngn-2, a bHLH transcription factor that plays an important role in the specification of epibranchial placode-derived sensory neurons. The expression levels of ngn-1 and ngn-2 decreased after fibroblast growth factor-2 treatment. These results suggest that Shh induces ngn-1 expression specifically and that expression of ngn-1 and ngn-2 is regulated by different mechanisms. The induction of ngn-1 expression by Shh suggests that this signaling molecule participates in the specification of trigeminal sensory neurons. We therefore examined the effect of Shh on the development of these neurons. Immunostaining using anti,ngn-1 demonstrated that Shh promotes ngn-1 expression in trigeminal neural crest cells. Trigeminal neural crest cells are derived from the posterior mesencephalon and the most-anterior rhombencephalon, and they contain a subset of precursors of trigeminal sensory neurons. Moreover, a subpopulation of trigeminal neural crest cells expressed the Shh receptor Patched. The number of cells that express Brn3a, a POU-domain transcription factor that plays an important role in differentiation of sensory neurons, also increased with Shh treatment. Our data suggest that Shh signaling is involved in the specification of trigeminal sensory neurons through the induction of ngn-1 expression. Furthermore, Shh promotes the differentiation of neural crest cells into trigeminal sensory neurons. Developmental Dynamics 227:554,551, 2003. © 2003 Wiley-Liss, Inc. [source]

    Expression of the ETS transcription factor ER81 in the developing chick and mouse hindbrain

    Yan Zhu
    Abstract ER81 is an ETS domain-containing transcription factor, which is expressed in various developing tissues and organs of the embryo and in pools of developing spinal motor neurons and proprioceptive sensory neurons. Analysis of mice lacking ER81 function showed that this gene played an important role in the establishment of sensory-motor circuitry in the spinal cord. Here, we investigate the expression pattern of er81 in the hindbrain of both chick and mouse embryos. We find that er81 is expressed in a subpopulation of inferior olive neurons, which send their projections to the caudal cerebellum. © 2002 Wiley-Liss, Inc. [source]

    MafA transcription factor identifies the early ret-expressing sensory neurons

    Laure Lecoin
    Abstract Dorsal root ganglia proceed from the coalescence of cell bodies of sensory neurons, which have migrated dorsoventrally from the delaminating neural crest. They are composed of different neuronal subtypes with specific sensory functions, including nociception, thermal sensation, proprioception, and mechanosensation. In contrast to proprioceptors and thermonociceptors, little is known about the molecular mechanisms governing the early commitment and later differentiation into mechanosensitive neurons. This is mainly due to the absence of specific molecular markers for this particular cell type. Using knockout mice, we identified the bZIP transcription factor MafA as the first specific marker of a subpopulation of "early c-ret" positive neurons characterized by medium-to-large diameters. This marker will allow further functional characterization of these neurons. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70:485,497, 2010 [source]

    Independent signaling pathways in ATP-evoked secretion of plasminogen and cytokines from microglia

    *Article first published online: 28 AUG 200, Kazuhide Inoue
    Abstract We investigated the action of ATP on the secretion of plasminogen, TNF-,, and IL-6 from microglia. ATP (10,100 ,M) stimulated the release of plasminogen from rat cultured microglia in a concentration-dependent manner with a peak response at 5,10 min after the stimulation. The release was dependent on extracellular Ca2+ and was blocked by pretreatment with oxidized ATP, a blocker of P2X7. UTP, an agonist of P2Y2, also stimulated the release of plasminogen from a subpopulation (about 20% of total cells) of cultured microglia. The release was also dependent on extracellular Ca2+, suggesting a role of stocker-operated calcium entry (SOC). ATP potently stimulated TNF-, release from 2 h after the stimulation with TNF-, mRNA expression in primary cultures of rat brain microglia. The TNF-, release was maximally elicited by 1 mM ATP and 2,- and 3,-O-(4-benzoylbenzoyl)-adenosine 5,-triphosphate (BzATP), a P2X7 selective agonist, suggesting the involvement of P2X7. This TNF-, release was correlated with a sustained Ca2+ influx. The release was inhibited by PD98059, an inhibitor of MEK1 which activates extracellular signal-regulated protein kinase (ERK), and SB203580, an inhibitor of p38 MAP kinase. However, both ERK and p38 were rapidly activated by ATP even in the absence of extracellular Ca2+. These results indicate that extracellular ATP triggers TNF-, release in rat microglia via P2X7 in a manner dependent on the sustained Ca2+ influx and via the ERK/p38 cascade independently of Ca2+ influx. ATP caused the mRNA expression and release of IL-6 in a concentration-dependent manner in MG-5. The physiological meaning of these independent release mechanisms is also discussed. Drug Dev. Res. 53:166,171, 2001. © 2001 Wiley-Liss, Inc. [source]

    Prevalence of epilepsy and seizures in the Navajo Nation 1998,2002

    EPILEPSIA, Issue 10 2009
    Karen Parko
    Summary Purpose:, To determine the prevalence of epilepsy and seizures in the Navajo. Methods:, We studied 226,496 Navajo residing in the Navajo Reservation who had at least one medical encounter between October 1, 1998 and September 30, 2002. We ascertained and confirmed cases in two phases. First, we identified patients with International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes signifying epilepsy or seizures using Indian Health Service (IHS) administrative data. Second, we reviewed medical charts of a geographic subpopulation of identified patients to confirm diagnoses and assess the positive predictive value of the ICD-9-CM codes in identifying patients with active epilepsy. Results:, Two percent of Navajo receiving IHS care were found to have an ICD-9-CM code consistent with epilepsy or seizures. Based on confirmed cases, the crude prevalence for the occurrence of any seizure (including febrile seizures and recurrent seizures that may have been provoked) in the geographic subpopulation was 13.5 per 1,000 and the crude prevalence of active epilepsy was 9.2 per 1,000. Prevalence was higher among males, children under 5 years of age, and older adults. Discussion:, The estimated prevalence of active epilepsy in the Navajo Nation is above the upper limit of the range of reported estimates from other comparable studies of U.S. communities. [source]

    Dual ETA/ETB vs. selective ETA endothelin receptor antagonism in patients with pulmonary hypertension

    C. F. Opitz
    Abstract Since the identification of endothelin as a key mediator in the pathogenesis of several diseases, including pulmonary arterial hypertension (PAH), the pharmacologic control of the activated endothelin system with endothelin receptor antagonists (ETRA) has been a major therapeutic achievement for the treatment of patients with PAH. To date, dual ETA/ETB and selective ETA receptor antagonists have clinically been evaluated. To answer the question of whether selective or dual ETRA is preferable in patients with PAH, experimental and clinical data with relevance to the pulmonary circulation are reviewed in this article. Whereas experimental and clinical data provide unambiguous evidence that ETA receptors mediate the detrimental effects of ET-1, such as vasoconstriction and cell proliferation, the elucidation of the role of ETB receptors has been more complex. It has been shown that there is a subpopulation of ETB receptors on smooth muscle cells and fibroblasts mediating vasoconstriction and proliferation. On the contrary, there is clear evidence that endothelial ETB receptors continue to mediate vasodilation, vasoprotection and ET-1 clearance despite the pathology associated with pulmonary hypertension. More difficult to assess is the net effect of these mechanisms in patients to be treated with ETRA. When considering the available data from controlled clinical trials, nonselectivity does not appear to carry a relevant clinical benefit for the treatment of patients with PAH when compared with selective ETA receptor antagonism. [source]

    Assessment of peripheral blood lymphocyte subsets in idiopathic myelofibrosis

    Francisco Cervantes
    Abstract: The objective of this study was to contribute to a better characterization of the immunological profile of idiopathic myelofibrosis (IM) at presentation by analysing the blood lymphocyte subsets and their possible correlations with other disease features. Absolute blood lymphocytes and lymphocyte subsets were assessed in 31 IM patients, compared with those from 34 healthy individuals, and correlated with the patients' main clinical, hematological and bone marrow histologic features. The mean lymphocyte count of the IM patients was 1.1 (SD 0.6)×109/L, versus 1.6 (SD 0.49)×109/L in controls (p=0.0006), with 24 of the 31 patients (77.4%) showing lymphocytopenia (<1.5×109/L). IM patients had significantly lower counts of CD3, CD4, CD8, and CD3,/CD56+ cells, and significantly higher CD3+/CD56+ lymphocyte counts. Although no significant differences were found between patients and controls with regard to CD19+/CD5+ cell counts, increased CD5+ B-cell lymphocytes were observed in three IM patients. In one of the latter patients, Ig gene rearrangement analysis of the heavy chain gene demonstrated such a subpopulation to be clonal, but the patient did not develop features of chronic lymphoid leukemia during a 5-yr follow-up. No correlation was found between the patients' blood lymphocyte counts and other disease features. We conclude that most IM patients have absolute lymphopenia, decreased T cells and increased cytotoxic T cells at diagnosis, and 10% of them show an increased CD5+ B-cell subpopulation. [source]

    Acquisition of regulatory function by human CD8+ T cells treated with anti-CD3 antibody requires TNF

    Vitaly Ablamunits
    Abstract Anti-CD3 mAb can modulate graft rejection and attenuate autoimmune diseases but their mechanism(s) of action remain unclear. CD8+ T cells with regulatory function are induced in vitro by Teplizumab, a humanized anti-CD3 antibody and inhibit responses of autologous and allogeneic T cells. They inhibit CD4+ T-cell proliferation by mechanisms involving TNF and CCL4, and by blocking target cell entry into G2/M phase of cell cycle but neither kill them, nor compete for IL-2. CD8+ Treg can be isolated from peripheral blood following treatment of patients with Type 1 diabetes with Teplizumab, but not from untreated patients. The induction of CD8+ Treg by anti-CD3 mAb requires TNF and signaling through the NF-,B cascade. The CD8+ Treg express CD25, glucocorticoid-induced TNF receptor family, CTLA-4, Foxp3, and TNFR2, and the combined expression of TNFR2 and CD25 identifies a potent subpopulation of CD8+ Treg. These studies have identified a novel mechanism of immune regulation by anti-CD3 mAb and markers that may be used to track inducible CD8+ Treg in settings such as chronic inflammation or immune therapy. [source]

    Functional role of human NK cell receptor 2B4 (CD244) isoforms

    Stephen O. Mathew
    Abstract 2B4 (CD244), a member of the signaling lymphocyte-activation molecule (SLAM/CD150), is expressed on all NK cells, a subpopulation of T cells, monocytes and basophils. Human NK cells express two isoforms of 2B4, h2B4-A and h2B4-B that differ in a small portion of the extracellular domain. In the present investigation, we have studied the functions of h2B4-A and h2B4-B. Our study demonstrated that these two isoforms differ in their binding affinity for CD48, which results in differential cytotoxic activity as well as intracellular calcium release by NK cells upon target cell recognition. Analysis of the predicted 3-D structure of the two isoforms showed conformational differences that could account for their differences in binding affinity to CD48. h2B4-A was able to mediate natural cytotoxicity against CD48-expressing K562 target cells and induce intracellular calcium release, whereas h2B4-B showed no effects. NK-92MI, U937, THP-1, KU812, primary monocytes, basophils and NK cells showed expression of both h2B4-A and h2B4-B whereas YT and IL-2-activated NK cells did not show any h2B4-B expression. Stimulation of NK cells through 2B4 resulted in decreased mRNA levels of both h2B4-A and h2B4-B indicating that down-regulation of 2B4 isoforms may be an important factor in controlling NK cell activation during immune responses. [source]