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61.
M.E. Andrs K. Gysling S. Araneda A. Venegas G. Bustos 《Journal of neuroscience research》1996,46(3):375-384
Antisense digoxigenin-labeled deoxyoligonucleotides probes and non-isotopic in situ hybridization (HIS) techniques have been used to explore the NMDA-NR1 receptor subunit mRNA distribution in different brain areas of rats which had their dopaminergic nigrostriatal pathway previously lesioned with intracerebral administration of 6-OH-dopamine (6-OH-DA). Intense and significant hybridization signals for NR1 mRNA were found in dentate gyrus and regions CA1-CA2-CA3 of the hippocampus, in layers II-III and V-VI of the cerebral cortex, and in the cerebellum of sham-treated rats. Basal ganglia structures such as the striatum exhibited few NR1 mRNA hybridization signals as compared to the hippocampus and cerebral cortex. In contrast, both zona compacta and reticulata of substantia nigra (SN) showed a reduced number of cells with nevertheless intense NR1 mRNA HIS signals. The NR1 mRNA distribution in the brain was affected in a brain regional selective manner by 6-OH-DA induced lesions of DA neuronal systems. A striking increase in NR1 mRNA HIS signals was observed in both striata after unilateral lesioning with 6-OH-DA. Instead, in SN compacta but not in reticulata, a moderate but significant bilateral reduction of NR1 mRNA was observed after unilateral 6-OH-DA injection. No significant changes in NR1 mRNA were detected in cerebral cortex and other brain regions after 6-OH-DA treatment. These studies, and others reported in the literature, support the view that extensive lesions of nigrostriatal DA-containing neurons in the brain may trigger compensatory or adaptative responses in basal ganglia structures such as striatum and substantia nigra which involve glutamatergic neurons and the genic expression of NMDA receptors. © 1996 Wiley-Liss, Inc. 相似文献
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63.
Geert Molenberghs Christel Faes Johan Verbeeck Patrick Deboosere Steven Abrams Lander Willem Jan Aerts Heidi Theeten Brecht Devleesschauwer Natalia Bustos Sierra Franoise Renard Sereina Herzog Patrick Lusyne Johan Van der Heyden Herman Van Oyen Pierre Van Damme Niel Hens 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(7)
BackgroundCOVID-19 mortality, excess mortality, deaths per million population (DPM), infection fatality ratio (IFR) and case fatality ratio (CFR) are reported and compared for many countries globally. These measures may appear objective, however, they should be interpreted with caution.AimWe examined reported COVID-19-related mortality in Belgium from 9 March 2020 to 28 June 2020, placing it against the background of excess mortality and compared the DPM and IFR between countries and within subgroups.MethodsThe relation between COVID-19-related mortality and excess mortality was evaluated by comparing COVID-19 mortality and the difference between observed and weekly average predictions of all-cause mortality. DPM were evaluated using demographic data of the Belgian population. The number of infections was estimated by a stochastic compartmental model. The IFR was estimated using a delay distribution between infection and death.ResultsIn the study period, 9,621 COVID-19-related deaths were reported, which is close to the excess mortality estimated using weekly averages (8,985 deaths). This translates to 837 DPM and an IFR of 1.5% in the general population. Both DPM and IFR increase with age and are substantially larger in the nursing home population.DiscussionDuring the first pandemic wave, Belgium had no discrepancy between COVID-19-related mortality and excess mortality. In light of this close agreement, it is useful to consider the DPM and IFR, which are both age, sex, and nursing home population-dependent. Comparison of COVID-19 mortality between countries should rather be based on excess mortality than on COVID-19-related mortality. 相似文献
64.
B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
65.
K Nandar LW Ang J Tey L James KM Kyi Win CBE Chee OT Ng JL Cutter YT Wang 《HIV medicine》2018,19(1):59-64
Cross‐matching of records between Singapore's tuberculosis and HIV registries showed that 3.3% of individuals with tuberculosis (TB) were coinfected with HIV (2000?2014), the TB incidence among individuals with HIV infection was 1.65 per 100 person‐years, and 53% of coinfections were diagnosed within 1 month of each other. The findings supported joint prevention programmes for early diagnosis and treatment. 相似文献
66.
Alberto E. Paniz‐Mondolfi MD MSc FFTM RCPS Carolina Talhari MD María F García Bustos MD PhD Tamara Rosales MD Wilmer E. Villamil‐Gomez MD Marilianna Marquez BSc Alexandra M. Pérez Alvarez Lic Biol Alejandra I. Tálamo Sánchez BSc 《International journal of dermatology》2017,56(12):1328-1341
Infant and young child skin diseases are among the most common features of morbidity throughout the tropics. Because the skin is directly exposed to the environment, it is considerably affected by climatic and local conditions such as vectors and microorganisms, as in the case of leishmaniasis. In America the observed magnitude of cutaneous leishmaniasis in children has led to the study of increased risk of exposure of this group due to the possibility of peri‐ and intradomiciliary transmission. The present review pretends to make a concrete approach all through the broad and main figures of this parasitic disease, including the clinical, physiopathological, epidemiological, diagnostic, and therapeutic aspects, in order to be used as a practical source of reference for pediatricians leading with tropical cutaneous pathology in the region. 相似文献
67.
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69.
Christine D. Pozniak Arundhati Sengupta Ghosh Alvin Gogineni Jesse E. Hanson Seung-Hye Lee Jessica L. Larson Hilda Solanoy Daisy Bustos Hong Li Hai Ngu Adrian M. Jubb Gai Ayalon Jiansheng Wu Kimberly Scearce-Levie Qiang Zhou Robby M. Weimer Donald S. Kirkpatrick Joseph W. Lewcock 《The Journal of experimental medicine》2013,210(12):2553-2567
70.
In our initial immunochemical study of the red blood cell (RBC) membrane proteins targeted in 20 cases of warm-antibody autoimmune hemolytic anemia (AHA), RBC eluates of 6 patients mediated immunoprecipitation (IP) of both band 3 and glycophorin A (GPA). This dual IP pattern had previously been observed with murine monoclonal antibodies (MoAbs) against the high frequency blood group antigen, Wrb (Wright), suggesting that the Wrb epitope may depend on a band 3-GPA interaction. Earlier, anti-Wrb had been identified serologically as a prominent non-Rh specificity of AHA autoantibodies. In the present study, 6 autoantibody eluates immunoprecipitating band 3 and GPA from common Wr(b+) RBCs were retested, in parallel with murine anti-Wrb MoAbs, against very rare Wr(a+b-)En(a+)RBCs. One patient's autoantibodies were unreactive with the Wr(b-) RBCs by either IP or indirect antiglobulin test (IAT) and were judged to have "pure" anti- Wrb specificity. Two other patients' autoantibodies displayed both IP and serologic evidence for anti-Wrb as a major component in combination with one or more additional specificities. However, among 3 other patients whose autoantibodies coprecipitated band 3 and GPA, there was no reduction in IP or IAT reactivity with Wr(b-) RBCs in 2 and only slight reduction in the third. We conclude (1) that human anti-Wrb autoantibodies, like their murine monoclonal counterparts, coprecipitate band 3 and GPA from human RBCs; but (2) that not all antibodies with this IP behavior have anti-Wrb serologic specificity, as defined by this donor's Wr(b-) RBCs. The possibility of an additional (non-Wrb) RBC epitope dependent on a band 3-GPA interaction is raised. 相似文献