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21.
Human platelet membrane glycoproteins IIb and IIIa (GPIIb and IIIa) were incorporated into phospholipid vesicles by the reverse-phase technique to assess the ability of GPIIb and IIIa to function as a Ca2+ channel. Movement of Ca2+ across the lipid bilayer was quantitated by injection of proteoliposomes with encapsulated Fura-2 into Ca2+ buffers and measurement of Fura-2 fluorescence as an indicator of Ca2+ influx. Reciprocally, to assess the function of proteins in an inside-out orientation, Ca2+-loaded vesicles were injected into Ca2+-free buffer and Ca2+ efflux monitored by a calcium electrode. Incorporation of the IIb-IIIa complex produced significant facilitation of Ca2+ movement across the lipid bilayer. No net transmembrane Ca2+ movement was seen with dissociated IIb and IIIa. Movement of Ca2+ was proportional to the transmembrane Ca2+ gradient. Ca2+ movement into the vesicles was inversely proportional to extravesicular NaCl from 25 to 150 mmol/L, analogous to several studies in the intact platelet. Adenosine triphosphate had no effect on Ca2+ movement into or out of the vesicles. Specific inhibition of a Ca2+ shift into the vesicles was seen with M148, a monoclonal antibody to IIb/IIIa, while no inhibition was observed with a panel of other anti-IIb/IIIa monoclonal antibodies. This suggests that a specific site on the complex or orientation of the complex is essential for calcium channel function. These data demonstrate that the GPIIb/IIIa complex can serve as a passive Ca2+ channel across a phospholipid bilayer and has the potential to play a role in Ca2+ flux across the platelet plasma membrane. 相似文献
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Juliana Maier Camila Silveira Sfreddo Ana Paula Pereira Reiniger Karla Zanini Kantorski Ulf ME Wikesj Carlos Heitor Cunha Moreira 《International dental journal》2021,71(2):127
BackgroundPeriodontal disease is a major cause of tooth loss. Few studies have evaluated the residual area of the periodontal ligament in extracted teeth and, to the best of our knowledge, none from Latin America have done so regarding indications for extraction. The aim of this study was to evaluate the residual periodontal ligament (RPL) with respect to indication for extraction in a sample of teeth from a Brazilian Public Health Service district.Materials and methodsAll teeth extracted within the Public Health Service district of Santa Maria, Brazil, over a 5-month period were requested for analysis. A total of 414 teeth eligible for measurement were stained and evaluated for RPL using a stereo microscope. Participating Public Health Service dentists completed a questionnaire detailing demographic variables and indication for each extracted tooth. The percentage of RPL was determined for each tooth. Comparisons of RPL between teeth extracted on periodontal versus other indications were made using the Mann-Whitney test.ResultsRPL averaged 34.8% for teeth extracted on periodontal indications versus 79.5% for other teeth (P ≤ 0.001). When considering teeth with an RPL ≥ 30% as possible to maintain, 189 (76%) of the teeth extracted on periodontal indications could have been maintained. When RPL cut-off limits of ≥ 40% or ≥ 50% are applied, 93 (37%) and 43 (17%) teeth, respectively, could have been maintained.ConclusionThis study suggests that strictly based on RPL, a large number of teeth extracted on periodontal indications conceivably could be maintained.Key words: Cross-sectional studies, Prognosis, Tooth extraction, Tooth loss 相似文献
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Patience ME Ocansey Irene A Kretchy Genevieve C Aryeetey Kofi Agyabeng Justice Nonvignon 《Ghana medical journal》2021,55(3):173
ObjectiveThis study assessed levels of anxiety, depression, and stress among family caregivers of children and adolescents with mental disorders in Ghana and the implication on medication adherence.DesignA cross-sectional study.SettingThe study was conducted at the outpatient departments of the three main public psychiatric hospitals in Ghana.ParticipantsTwo hundred and ten non-paid family caregivers of children and adolescents with mental disorders were recruited for this study.Main Outcome MeasureThe study assessed symptoms of anxiety, depression and stress among the caregivers and estimated caregiver-reported medication adherence.ResultsAbout 56.2%, 66.2% and 78% of the caregivers experienced severe anxiety, severe depression and moderate to severe stress symptoms respectively. From the multiple logistic regression model, while anxiety was significantly affected by religion and education, depression was influenced by sex, age, marital status, proximity to facility, and employment status. Female caregivers had about four times higher odds of being depressed compared to male caregivers (aOR: 3.81, 95% CI: 1.66 – 8.75). The caregiver-reported medication adherence was 11.9%. Anxiety was significantly predictive of medication adherence.ConclusionMost family caregivers of children and adolescents with mental disorders experienced symptoms of anxiety, depression and stress with anxiety having implications for medication adherence. The study findings underscore the need to consider psychological characteristics of caregivers and the provision of mental health support for them, as part of the routine health care for children and adolescents with mental disorders.FundingNone indicated 相似文献
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Stroke survivors’ and carers’ experiences of a systematic voiding programme to treat urinary incontinence after stroke 下载免费PDF全文
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Comparison of various techniques for determining viability of Paracoccidioides brasiliensis yeast-form cells. 总被引:10,自引:0,他引:10 下载免费PDF全文
A Restrepo L E Cano C de Bedout E Brummer D A Stevens 《Journal of clinical microbiology》1982,16(1):209-211
The viability of Paracoccidioides brasiliensis yeast-form cells was determined by colony-forming units, direct fluorescent staining, and production of germ tubes in slide culture. The first procedure was unreliable and time consuming; the latter two showed better correlation with hemacytometer total cell counts and required significantly less time. 相似文献