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121.

Aims

Atrial fibrillation and flutter remain an important cause of morbidity in adults with atrial septal defect (ASD). This study aimed at investigating predictors for late (≥ 1 month after repair) atrial arrhythmia.

Methods

Patients who underwent ASD closure after the age of 18 years, were selected through the databases of three medical centres in Belgium. Preprocedural, periprocedural and follow-up data were extracted. Univariate and multivariate Cox-regression analysis was performed. Kaplan-Meier analysis was performed for any independent predictor of late atrial arrhythmia.

Results

A total of 155 patients (38 men and 117 women) was included. Twenty-four patients (median age 48.3 years, range 19.9-79.8) underwent surgical and 131 (median age 57.6 years, range 18.2-86.9) underwent transcatheter closure. Thirty-nine patients (25.2%) presented with late atrial arrhythmia. Male gender (P = 0.008), creatinine (P = 0.002), atrial arrhythmia before (P < 0.0001) and within 1 month after repair (P = 0.001) and a mean pulmonary artery pressure (mPAP) ≥ 25 mm Hg (P < 0.0001) correlated with late atrial arrhythmia in univariate Cox-regression analysis. Multivariate analysis showed that mPAP ≥ 25 mm Hg (HR 3.72; 95%CI 1.82-7.59; P < 0.0001) and the presence of atrial arrhythmia before (HR 3.22; 95%CI 1.56-6.66; P = 0.002) and within 1 month after repair (HR 2.08; 95%CI 2.08-15.92; P = 0.001) were predictive of late atrial arrhythmia. Kaplan-Meier analysis showed that patients with a mPAP ≥ 25 mm Hg had a higher risk at developing late atrial arrhythmia (P < 0.0001).

Conclusion

In patients with ASD type secundum, a mPAP ≥ 25 mm Hg is an independent predictor of late atrial arrhythmia. The presence of pulmonary hypertension before repair should raise awareness for atrial arrhythmias and may be used to guide therapy.  相似文献   
122.
Functional analysis of neutrophils requires isolation of these cells in the laboratory. Current isolation procedures are time consuming and can potentially activate the resting neutrophils. Thus, in this present study, we have optimised an existing laboratory protocol for human neutrophil isolation from peripheral blood. Twenty ml of blood samples were subjected to optimised density gradient separation and dextran sedimentation to obtain a pure population of neutrophils. The efficacy of the optimised manual post isolation of neutrophils was compared with pre isolation count performed by an automated haematology analyzer. The recovery of neutrophils via our optimised methods was 65.5% in comparison with neutrophils counts at pre-isolation. The morphological analysis of isolated neutrophils indicated the purity level more than 95% using Leishman staining. Our optimised laboratory procedures for neutrophils isolation successfully harvested neutrophils with good viability, purity and post recovery yield. This procedure provides an ideal platform to separate neutrophils for in vitro studies.  相似文献   
123.
Detection and quantification of Hb subtypes of human blood is integral to presumptive identification of thalassaemias. It has been used in neonatal screening of thalassaemia and Hb variants. The use of discarded red blood cells following processing of the cord blood for stem cells provides readily available diagnostic material for thalassaemia screening. In this study, we determined the range of Hb subtypes in 195 consecutive cord blood samples collected for cord blood banking. The 'cord blood samples' analysed were those of the remaining red blood cells after the cord blood was processed for stem cell storage. Quantification of Hb subtypes by high performance liquid chromatography (HPLC) was done on BioRad Variant II Hb testing system. Only 73 (36.5%) of the samples could be analyzed neat without dilution. With a 1:300 dilution with wash solution the acceptable area as recommended by the manufacturer for reading of a C-gram within the 1 to 3 million ranges were achieved in all. Eighteen (9%) 12 showed classical Hb Barts (y4) prerun peaks were confirmed by Sebia Hydrasys automated Hb gel electrophoresis and quantified by Sebia Capillarys 2 capillary electrophoresis. Only 1 (0.5%) was presumptively identified with HbH disease. Due to the limited number of samples no beta-thalassaemia major, Hb E beta-thalassaemia and Hb Barts hydrops fetalis were found. The HPLC assay was possible at a cost US$ 5 per sample and a turnover time of 10 samples per hour without technical difficulties. This study reports an effective and valuable protocol for thalassaemia screening in red blood cells which would otherwise be discarded during cord blood processing. Cord blood with severe and intermediate forms of thalassaemia can be preselected and not stored.  相似文献   
124.
125.
Bone vasculature and bone marrow vascular niches supply oxygen, nutrients, and secrete angiocrine factors required for the survival, maintenance, and self-renewal of stem and progenitor cells. In the skeletal system, vasculature creates nurturing niches for bone and blood-forming stem cells. Blood vessels regulate hematopoiesis and drive bone formation during development, repair, and regeneration. Dysfunctional vascular niches induce skeletal aging, bone diseases, and hematological disorders. Recent cellular and molecular characterization of the bone marrow microenvironment has provided unprecedented insights into the complexity, heterogeneity, and functions of the bone vasculature and vascular niches. The bone vasculature is composed of distinct vessel subtypes that differentially regulate osteogenesis, hematopoiesis, and disease conditions in bones. Further, bone marrow vascular niches supporting stem cells are often complex microenvironments involving multiple different cell populations and vessel subtypes. This review provides an overview of the emerging vascular cell heterogeneity in bone and the new roles of the bone vasculature and associated vascular niches in health and disease. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
126.
Improved collagen bilayer dressing for the controlled release of drugs   总被引:1,自引:0,他引:1  
A novel bilayer dressing has been developed from bovine succinylated collagen. The dressing contains an antibiotic, Ciprofloxacin, for both immediate and time-regulated release for controlling the infection, as the infected open wounds need special care. The dressing consists of a sponge and a film, both prepared from succinylated bovine collagen. The sponge has a smooth surface on one side; its rough surface on the other side forms the bilayer system with the film. Both sponge and film act as an anionic reservoir to hold the cationic Ciprofloxacin. The drug, after dispersing in poly (N-vinyl-2-pyrrolidione) (PVP) solution is allowed to spread in the bilayer system by diffusion. The drug stays in the bilayer system because of ionic binding, but starts releasing when comes in contact with the wound. Release of the drug is immediate, but it is regulated by ionic binding between the drug and succinylated collagen. The wound exudates, and there is a polarity-controlled release of the drug from the bilayer system. The PVP and bilayer system permits only time-regulated release, and the system lasts up to 5 days with therapeutically sufficient drug availability.  相似文献   
127.
The nature of addiction depends on various factors. The tendency to have already used several addictive substances and to seek high sensation experiences as a result of specific personality traits may lead to extreme and peculiar forms of addictions. Even belonging to specific social and cultural background may lead to such forms of addiction such as intentional snake bite and willful envenomation. In this article, we have discussed the peculiarities and practical insight of such addiction to snake venom. The possible molecular mechanism behind such venom-mediated reinforcement has also been highlighted. Finally, we have stressed upon the treatment and de-addiction measures.  相似文献   
128.
129.
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT
• Widow spider antivenoms, including redback spider antivenom, are often given by the intramuscular route.
• No studies have measured widow spider antivenom following intramuscular or intravenous antivenom.
WHAT THIS STUDY ADDS
• Intramuscular redback spider antivenom is not detectable in serum for at least 3–5 h after treatment. Intravenous antivenom is detectable 30 min after intravenous infusion.
• Intramuscular antivenom may not be an effective administration route.
AIMS There are no studies measuring antivenom concentrations following intramuscular administration. This study aimed to compare antivenom concentrations following intravenous and intramuscular administration of redback spider antivenom (RBSAV).
METHODS Twenty patients recruited to a controlled trial comparing intramuscular and intravenous administration of antivenom had serial blood samples collected at 30 min intervals for 2 h after the administration of one or two doses of antivenom. Antivenom concentration was measured using an enzyme immunoassay.
RESULTS Ten patients received intramuscular antivenom but antivenom could not be detected in serum after either one or two vials, at any time point. The median time of the final sample after commencement of antivenom treatment in these patients was 3.2 h (1.8–5 h). Ten patients received intravenous antivenom (three one vial and seven two or more vials) and antivenom was detected in all patients.
CONCLUSIONS RBS AV given by the intramuscular route is unlikely to be effective in the treatment of redback (widow) spider bite.  相似文献   
130.
Mast cells originate from pluripotent progenitor cells in bone marrow and are major players in the inflammation process. The involvements of mast cells in various cardiovascular complications such as arrhythmias, ischaemia reperfusion injury and graft rejection are well documented. Moreover, recent studies suggest the involvement of mast cells in cardiac hypertrophy and heart failure. The present review focuses on the role of mast cells in the development of cardiac hypertrophy and heart failure.  相似文献   
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