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71.
Prolonged QT interval is an independent risk factor for development of ventricular arrhythmias. Haloperidol is one of the drugs inducing QT prolongation. Previous studies showed that haloperidol affects not only QT duration but also heart rate (RR interval). The present work focused on relationship between QT and RR and its changes under acute and chronic haloperidol administration. The study included 14 male guinea pigs divided into control and haloperidol-treated group. After 21-days administration of haloperidol or vehiculum, electrograms in isolated hearts were recorded. QT/RR and dQT/dRR coupling were calculated. Chronic haloperidol administration significantly decreases the coupling between QT and RR. Acute haloperidol exposure significantly decreases the dQT/dRR coupling in both treated and untreated guinea pig hearts. Flatter QT/RR relationship reveals a lack of QT adaptation to increased heart rate. It should be emphasized that in such situation ECG recording will not show significant QT prolongation evaluated according to clinical rules. However, if QT interval does not adapt to increased heart rate sufficiently, the risk of ventricular arrhythmias may be increased despite practically normal QT interval length. The results are supported by findings in biochemical analyses, which proved eligibility of the used model.  相似文献   
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Objective: The goal of this study was to compare rates of asthma action plan use by limited English proficiency (LEP) caregivers to English proficient (EP) caregivers. Methods: A cross-sectional bilingual survey was distributed at an urban, academic, pediatric emergency department (PED). Surveys were completed by adult caregivers of children with asthma who sought PED care for asthma related chief complaints. LEP was defined as caregiver ability to speak English less than “very well”. Data were analyzed using Fisher’s exact test and odds ratios (OR). Results: One hundred seven surveys were completed and analyzed. Fifty-one surveys (48%) were completed by LEP caregivers and 56 (52%) by EP caregivers. A 25% difference (p?=?.01) in action plan use rates between LEP caregivers (39%) and EP caregivers (64%) was observed. EP alone was associated with action plan use (OR 2.8 [95% CI 1.3–6.1]). Variables not associated with plan use included mother acting as caregiver (OR 2.1 [95% CI 0.7–7.0]), age of child >7 years (OR 1.0 [95% CI 0.5–2.4]), caregiver education?≥?associate degree (OR 1.4 [95% CI 0.6–3.0]), private insurance (OR 0.7 [95% CI 0.3–1.8]), White race (OR 0.7 [95% CI 0.2–2.2]), Latino ethnicity (OR 0.5 [95% CI 0.2–1.3]) and a federally qualified health center (OR 0.8 [95% CI 0.3–2.0]). The main caregiver reasons for plan use were feeling that a plan works/gets results, helps with symptom management and appreciation towards physician attentiveness when a plan is prescribed. The main caregiver reasons for non plan use were they were not informed/given an action plan or perceived the child’s asthma as mild/well controlled. Conclusion: Compared with EP caregivers, those with LEP experience disparate rates of asthma action plan use.  相似文献   
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CD33 rs3865444:C>A single nucleotide polymorphism (SNP) has been previously associated with the risk of late‐onset Alzheimer's disease (LOAD); however, the results have been inconsistent across different populations. CD33 is a transmembrane receptor that plays an important role in AD pathogenesis by inhibiting amyloid β42 uptake by microglial cells. In this study, we aimed to validate the association between rs3865444 and LOAD risk in the Slovak population and to evaluate whether it was affected by the carrier status of the major LOAD risk allele apolipoprotein (APOE) ε4. CD33 rs3865444 and APOE variants were genotyped in 206 LOAD patients and 487 control subjects using the polymerase chain reaction–restriction fragment length polymorphism method and direct sequencing, respectively. Logistic regression analysis revealed a significant association of rs3865444 A allele with a reduced LOAD risk that was only present in APOE ε4 allele carriers (AA + CA versus CC: p = .0085; OR = 0.45; 95% CI = 0.25?0.82). On the other hand, no such association was found in subjects without the APOE ε4 (p = .75; OR = 0.93; 95% CI = 0.61?1.42). Moreover, regression analysis detected a significant interaction between CD33 rs3865444 A and APOE ε4 alleles (p = .021 for APOE ε4 allele dosage and p = .051 for APOE ε4 carriage status), with synergy factor (SF) value of 0.49 indicating an antagonistic effect between the two alleles in LOAD risk. In conclusion, our results suggest that CD33 rs3865444:C?A substitution may reduce the risk of LOAD in Slovaks by antagonizing the effect conferred by the major susceptibility allele APOE ε4.  相似文献   
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Eruption requires synchrony of the tooth with the surrounding tissues, particularly the bone. One important step during eruption is remodelling of the alveolar bone at the base of the tooth and along the roots. Expression of BMP6 was reported to be increased in the basal half of the dental follicle prior to eruption and inhibition of BMP6 affected bone formation at the base of the alveolar crypt. The aim of this study was to further investigate BMP6 protein in relation to tooth eruption and the corresponding bone remodelling using temporospatial correlations of BMP6 localization with morphogenetic events (proliferation, differentiation, apoptosis and bone apposition/resorption), other BMPs (BMP2 and BMP7) and three-dimensional images of tooth–bone development. BMP6 expression pattern was mapped in the mandibular molar teeth and related structures around eruption. Localization of BMP6 dominated in osteoblasts, in regions of bone formation within the alveolar crypt. These findings positively correlated with proliferation at the tooth base region, osteocalcin expression in the osteoblasts/osteocytes and BMP2 and BMP7 presence in the alveolar bone surrounding the tooth. Osteoclast activity and apoptotic elimination in the root region gradually decreased before eruption and totally ceased at eruption stages. Generally, BMP6 positively correlated with BMP2, BMP7 and osteocalcin-positive osteoblasts, and areas of bone remodelling. Moreover, BMP6 was found in the periodontium and cementoblasts. BMP6 expression in the alveolar bone accompanied tooth eruption. Notably, the expression pattern of BMP6 in the bone did not differ around individual molar teeth at the same stage of development. The expression of BMP6 in periodontal ligaments may contribute to interaction between the tooth and bone during the eruption and anchoring process.  相似文献   
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