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61.
Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献
62.
Mitochondrial DNA A3243G mutation in patients with early- or late-onset type 2 diabetes mellitus in Hong Kong Chinese 总被引:6,自引:0,他引:6
Ng MC Yeung VT Chow CC Li JK Smith PR Mijovic CH Critchley JA Barnett AH Cockram CS Chan JC 《Clinical endocrinology》2000,52(5):557-564
BACKGROUND: AND OBJECTIVES: The mitochondrial DNA A to G mutation at nucleotide 3243 (mt3243) is associated with a subtype of diabetes characterized by maternal transmission and deafness. We have previously reported a 2.7% prevalence of this mutation in a cohort of young patients with either type 1 or type 2 diabetes. In this study, we aimed to confirm this finding by examining for the prevalence of this mutation in a large-scale study. SUBJECTS AND METHODS: Nine hundred and six unrelated Chinese patients with type 2 diabetes and 213 nondiabetic controls were studied. The presence of mt3243 mutation was determined by polymerase chain reaction amplification and ApaI digestion. RESULTS: This mutation was found in four of 133 (3.0%) patients with early onset (= 40 years) diabetes who also had a positive maternal family history, and in one of 348 (0.3%) patients with late-onset (> 40 years) diabetes and no family history. Basal pancreatic beta-cell function, as assessed by fasting plasma C-peptide, was variable amongst mutation carriers, and did not correlate with the level of heteroplasmy of mutation. CONCLUSIONS: In agreement with most studies, our results suggest that despite the high prevalence of positive maternal family history of diabetes amongst our type 2 diabetic patients, mt3243 mutation was not a major cause of diabetes in either early- or late-onset diabetic patients in Hong Kong. The role of other genetic, environmental and intrauterine factors needs further investigation. 相似文献
63.
Andrea LA?TOVKOVá Pavlina KLUSá?KOVá Zdenka FENCLOVá Vincent BONNETERRE Daniela PELCLOVá 《Industrial health》2015,53(6):562-568
The objective of this study is to describe a case-series of potassium aluminium
tetrafluoride (KAlF4)-induced occupational asthma (OA) and/or occupational
rhinitis (OR). The study involves five patients from a heat-exchanger production line who
were examined (including specific inhalation challenge tests) for suspected OA and/or OR
caused by a flux containing almost 100% KAlF4 − with fluorides’ workplace air
concentrations ranging between 1.7 and 2.8 mg/m3. No subject had a previous
history of asthma. All five patients had a positive specific challenge test (three
patients were diagnosed with OA alone, one with OR and one with both OR and OA). At the
follow-up visit, after three years on average, all patients needed permanent
corticosteroid therapy (four topical, one oral). After elimination from the exposure, only
one of the observed subjects gave an indication of an improvement, two subjects stabilized
and two worsened. Our case series focuses on the correlation between patients’ exposure to
fluorides in air-conditioner production and the subsequent occurrence of OR/OA. Currently,
it is uncertain whether these OR/OA were caused by hypersensitivity or irritation. 相似文献
64.
目的探讨腹腔镜手术对不孕症患者的诊断及治疗价值。方法回顾性分析新疆医科大学第一附属医院2010年9月-2014年5月收治的319例不孕症患者的临床资料,对所有患者行腹腔镜下诊断及相应的手术治疗(包括盆腔粘连分解、输卵管造口术、输卵管灼断术等)。结果 319例患者腹腔镜术中检查与术前子宫输卵管碘油造影结果的符合率为72.1%(230/319),其中有43例术中发现子宫肌瘤,56例术中发现输卵管系膜囊肿,8例患者术中发现子宫内膜异位症,有2例患者诊断为盆腔结核,1例术中发现结肠肌瘤(术前考虑卵巢囊肿),其余为不同程度的盆腔慢性炎症。轻度粘连69例,妊娠21例,宫外孕2例,妊娠率33.33%。中重度粘连250例,其中行灼断术34例,灼断术患者后行体外受精及胚胎移植(IVF-ET),妊娠13例,妊娠率38.23%(13/34)。其余216例,失访3例,妊娠31例,宫外孕3例、妊娠率15.9%。结论腹腔镜对诊断输卵管性不孕及盆腔疾病有重要价值,子宫输卵管造影仅能初级筛查,诊断价值有限。在治疗输卵管粘连梗阻中,腹腔镜的治疗价值有待进一步探讨,临床预后与盆腔炎症的程度有关,应个体化选择手术方案。 相似文献
65.
66.
Elena Makovac Sarah N Garfinkel Andrea Bassi Barbara Basile Emiliano Macaluso Mara Cercignani Giovanni Calcagnini Eugenio Mattei Daniela Agalliu Pietro Cortelli Carlo Caltagirone Marco Bozzali Hugo Critchley 《Neuropsychopharmacology》2015,40(7):1649-1658
Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets. 相似文献
67.
Sarah N. Garfinkel Adam B. Barrett Ludovico Minati Raymond J. Dolan Anil K. Seth Hugo D. Critchley 《Psychophysiology》2013,50(6):505-512
Mental functions are influenced by states of physiological arousal. Afferent neural activity from arterial baroreceptors at systole conveys the strength and timing of individual heartbeats to the brain. We presented words under limited attentional resources time‐locked to different phases of the cardiac cycle, to test a hypothesis that natural baroreceptor stimulation influences detection and subsequent memory of words. We show memory for words presented around systole was decreased relative to words at diastole. The deleterious memory effect of systole was greater for words detected with low confidence and amplified in individuals with low interoceptive sensitivity, as indexed using a heartbeat counting task. Our observations highlight an important cardiovascular channel through which autonomic arousal impacts a cognitive function, an effect mitigated by metacognition (perceptual confidence) and interoceptive sensitivity. 相似文献
68.
A New Variant of Hereditary Hemolytic Anemia With Stomatocytosis and Erythrocyte Cation Abnormality 总被引:4,自引:1,他引:4
MILLER DENIS R.; RICKLES FREDERICK R.; LICHTMAN MARSHALL A.; LA CELLE PAUL L.; BATES JONATHAN; WEED ROBERT I. 《Blood》1971,38(2):184-204
A new variant of congenital hemolyticanemia associated with stomatocytosis,reticulocytosis, decreased osmotic fragility, type I autohemolysis and shortened erythrocyte survival without specific splenic sequestration was discoveredin three siblings of Swiss-German ancestry. Increased intracellular sodium(two to three times normal) and slightlydecreased intracellular potassium weredetected. Total sodium efflux was eight-fold greater than normal but total potassium influx was normal and ouabain-sensitive potassium influx was decreased.The ouabain-sensitive sodium efflux:potassium influx ratio was 26:1 ratherthan the 3:2 ratio noted in normal cells.The consanguineous parents, four othersiblings, and 44 other family membershad mild stomatocytosis, reticulocytosis,and, when studied, decreased osmoticfragility, increased autohemolysis, intermediate abnormalities of cation content,cation flux, and moderate shortening oferythrocyte survival. Autosomal dominant inheritance was suggested. Noabnormalities of RBC enzymes, hemoglobin or lipids were observed. No abnormalities of membrane protein weredetected on acrylamide gel. Substratedepletion of these hypermetabolic cellsresulted in intracellular dehydrationwith potassium loss in excess of sodiumgain and decreased deformability. Although the exact nature of the defectresponsible for hemolysis is unknown,this syndrome differs from other hereditary hemolytic anemias associated withstomatocytosis. Submitted on December 21, 1970 Revised on March 16, 1971 Accepted on March 29, 1971 相似文献
69.
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
70.
目的 对比分析单纯后路内固定+一期经腰椎间孔病椎间病灶清除(TLIF)与经典的前后联合手术在布氏杆菌性脊柱炎患者中的临床疗效及安全性。 方法 对我院2015年1月至2017年12月收治的93例布病性脊柱炎患者的临床资料进行分析。按手术方式分为观察组(45例)和对照组(48例)。对两组患者的基础数据、临床指标、术前术后各项指标水平以及术后并发症、植骨治愈情况。 结果 观察组与对照组基础数据比较,差异无统计学意义(P>0.05)。观察组患者的手术时间、住院天数、术中出血量及术后下床时间均明显低于对照组(P<0.01)。两组患者术后3个月的ODI、VAS、CRP、ESR及Cobb角均明显低于术前(P<0.05);术后3个月,观察组患者的ODI、VAS、CRP、ESR及Cobb角均明显低于对照组(P<0.05)。观察组术后并发症发生率(4.4%)明显低于对照组(25.0%)(Χ2=7.674,P<0.01)。 结论 TLIF治疗布氏杆菌性脊柱炎患者的临床疗效突出,安全性较好,更有利于患者术后身体的恢复。 相似文献