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1.
OBJECTIVE: Complete allograft denervation occurs during heart transplantation. Partial ventricular sympathetic reinnervation may develop one year or later after transplantation and can be measured with iodine-123-meta-iodobenziylguanidine (MIBG) uptake. Aim of this study was to assess sinus node sympathetic reinnervation measured with heart rate variability and ventricular sympathetic reinnervation evaluated with MIBG. METHODS: Twelve patients and 14 healthy controls were included. In patients, MIBG scintigraphy with early and late imaging was performed. Heart to mediastinum ratio (HMR) was calculated and patients were divided in groups with (HMR>1.3) and without left ventricular reinnervation (HMR<1.3). Bipolar ECG with high sampling rate and resolution was recorded over 8.5 min in supine position and in upright position after 10 min interval. R-R intervals in time domain and heart rate variability in frequency domain through spectral power analysis of R-R intervals were analysed to evaluate sinus node reinnervation. Spectral power in low frequency range (0.04-0.15 Hz) above 4.5 ms(2) was considered as sinus node sympathetic reinnervation. RESULTS: Six (50%) patients had evidence of left ventricular sympathetic reinnervation on scintigraphy. Sinus node sympathetic reinnervation based on heart rate variability was detected in 6 (50%) patients in supine, and in 4 (33%) patients in upright body position. Four patients groups were discerned: (1) with ventricular and sinus node sympathetic reinnervation, (2) with sinus node sympathetic reinnervation, (3) with ventricular sympathetic reinnervation and (4) without atrial or ventricular sympathetic reinnervation. Ventricular reinnervation process was time dependent and sinus node reinnervation was not. CONCLUSIONS: Simultaneous ventricular sympathetic reinnervation assessed by MIBG and sinus node sympathetic reinnervation assessed by heart rate variability in supine as in upright position were detected only in two patients (17%). The results of our study show that eventual sinus node sympathetic reinnervation and left ventricular sympathetic reinnervation do not occur simultaneously.  相似文献   
2.
The antibiotic 5-nitrofurantoin (5-NF) has been used widely for the treatment of urosepsis in children during the last 20 years. Recent experimentation suggests the need for reevaluating its genotoxic potential. Because of possible differences in the metabolism and clearance of 5-NF in young and adult animals, we conducted a study to determine whether micronuclei caused by 5-NF were age-related. The in vivo micronucleus (MN) assay was performed on 3- and 8-week-old mice given single intraperitoneal injections of 5, 10, and 50 mg/kg 5-NF. Blood samples from the tail vein were taken before injection (baseline) and at 48, 96, 168, and 336 hr (2 weeks) after the treatment. One thousand reticulocytes were analyzed for micronuclei from each animal. Compared to similar baseline values for young and adult mice, 5-NF caused a significant increase in MN frequency in both age groups. The mean MN frequency in the young animals was higher than in the adult animals for each dose and sampling time. MN frequencies remained significantly elevated in young animals even 2 weeks after exposure to 5-NF. The results of the study confirm the genotoxic potential of 5-NF in young and adult animals, and indicate that young animals are more sensitive to the genotoxic effects of 5-NF than adult mice and that the response in young mice persists for a significantly longer time. These findings may be related to poorly developed mechanisms of xenobiotic detoxification and renal elimination in young animals.  相似文献   
3.
AimTo investigate the risk factors and the outcomes of extracorporeal membrane oxygenation (ECMO) in pediatric patients treated at the University Hospital Center Zagreb, the largest center in Croatia providing pediatric ECMO.MethodsThis retrospective study enrolled all the pediatric patients who required E-CPR from 2011 to 2019. Demographic data, cardiac anatomy, ECMO indications, ECMO complications, and neurodevelopmental status at hospital discharge were analyzed.ResultsIn the investigated period, E-CPR was used in 16 children, and the overall survival rate was 37.5%. Six patients were in the neonatal age group, 5 in the infant group, and 5 in the “older” group. There was no significant difference between the sexes. Four patients had an out-of-hospital arrest and 12 had an in-hospital arrest. Twelve out of 16 patients experienced renal failure and needed hemodialysis, with 4 out of 6 patients in the survivor group and 8 out of 10 in the non-survivor group. Survivors and non-survivors did not differ in E-CPR duration time, lactate levels before ECMO, time for lactate normalization, and pH levels before and after the start of ECMO.ConclusionThe similarity of our results to those obtained by other studies indicates that the ECMO program in our hospital should be maintained and improved.

The use of extracorporeal cardiopulmonary resuscitation (E-CPR) is increasing (1). E-CPR is defined as an initiation of extracorporeal membrane oxygenation (ECMO) during active chest compressions. Its main goal is to provide immediate cardiovascular support to patients who do not react to CPR (2) and to lead to survival and a better neurological outcome (3). After administering CPR for more than 30 minutes, survival with conventional CPR measures ranges between 0%-5% (4,5).The most recent systematic review by the International Liaison Committee on Resuscitation from 2015 recommended that E-CPR should be considered for children with underlying cardiac conditions who have an in-hospital cardiac arrest when appropriate protocols, expertise, and equipment are available (6). According to the Extracorporeal Life Support Organization (ELSO) registry from 2017 (7), more than 60 000 people received extracorporeal life support (ECLS), between 2009 and 2015, with an overall survival rate of 61% (7). Pediatric ECMO experience in Slovenia shows that ECMO programs may be incorporated in smaller hospitals in the region (8-10). The ELSO database includes data on all reported pediatric ECMO runs, including those conducted with E-CPR, and in patients with congenital heart surgery and neonates with diaphragmatic hernia or meconium aspiration syndrome, etc. During the 6-year period, 3005 E-CPR runs were reported, with an overall survival to hospital discharge of 43% (7). A survival rate of 31% was reported by Ergűn et al (11) and in E-CPR patients with severe burn injury (12). The longer the CPR duration time, the lower was the survival to discharge rate. Matos et al reported an E-CPR survival-to-discharge rate of 33% after >35 min of chest compressions (13). Other studies reported that the overall survival rate of pediatric E-CPR cases was growing, with better neurological outcomes than among the patients in the CPR group only (14). Pilar et al found that in 73 pediatric cardiac patients requiring cardiopulmonary resuscitation for >30 min (15), the survival to hospital discharge was 43.8%, with 3/4 of the patients having normal neurological function or mild neurological disability (15). Based on ELSO registry, approximately 10% of all ECMO patients meet brain death criteria (7). One of the biggest single-center studies, involving 184 pediatric ECPR patients (16), showed a successful ECMO weaning in 63% of the patients and the overall survival rate to hospital discharge of 43%. In the same study, the risk factors linked to increased mortality were presupport pH<7.1, mechanical complications, and neurological complications (16). The E-CPR use can involve many complications, not necessarily linked to factors preceding cardiac arrest, such as low cardiac output syndrome or irreversible respiratory failure (17). Furthermore, common complications of ECMO treatment are fluid overload and acute kidney injury (18). Many studies showed renal replacement therapy (RRT) to be negatively associated with survival (15,16,18,19).This study assessed the risk factors and the outcomes of ECMO in the largest Croatian center providing pediatric E-CPR experience over nine years and compared the survivor and the non-survivor group.  相似文献   
4.
Paramyxoviruses of type 1 (PMV-l) isolated from pigeons were genetically analyzed. A part of the fusion and the matrix protein genes were amplified and sequenced, Typical amino acid sequences associated with virulence were determined at the fusion protein cleavage site in all PMV-1 isolates. All Slovene pigeon PMV-1 strains share high amino acid sequence similarity with other pigeon strains. In the phylogenetic tree, they are clustered together with pigeon PMV-1 isolates with moderate pathogenicity. Phylogenetic analysis obtained from the fusion and the matrix protein gene alignments showed the same branching order. Viruses circulating among pigeons were found to form quite unique lineage of virulent NDV strains.  相似文献   
5.
A 42-kDa fragment from the C terminus of major merozoite surface protein 1 (MSP1) is among the leading malaria vaccine candidates that target infection by asexual erythrocytic-stage malaria parasites. The MSP1(42) gene fragment from the Vietnam-Oak Knoll (FVO) strain of Plasmodium falciparum was expressed as a soluble protein in Escherichia coli and purified according to good manufacturing practices. This clinical-grade recombinant protein retained some important elements of correct structure, as it was reactive with several functional, conformation-dependent monoclonal antibodies raised against P. falciparum malaria parasites, it induced antibodies (Abs) that were reactive to parasites in immunofluorescent Ab tests, and it induced strong growth and invasion inhibitory antisera in New Zealand White rabbits. The antigen quality was further evaluated by vaccinating Aotus nancymai monkeys and challenging them with homologous P. falciparum FVO erythrocytic-stage malaria parasites. The trial included two control groups, one vaccinated with the sexual-stage-specific antigen of Plasmodium vivax, Pvs25, as a negative control, and the other vaccinated with baculovirus-expressed MSP1(42) (FVO) as a positive control. Enzyme-linked immunosorbent assay (ELISA) Ab titers induced by E. coli MSP1(42) were significantly higher than those induced by the baculovirus-expressed antigen. None of the six monkeys that were vaccinated with the E. coli MSP1(42) antigen required treatment for uncontrolled parasitemia, but two required treatment for anemia. Protective immunity in these monkeys correlated with the ELISA Ab titer against the p19 fragment and the epidermal growth factor (EGF)-like domain 2 fragment of MSP1(42), but not the MSP1(42) protein itself or the EGF-like domain 1 fragment. Soluble MSP1(42) (FVO) expressed in E. coli offers excellent promise as a component of a vaccine against erythrocytic-stage falciparum malaria.  相似文献   
6.
Journal of Public Health - Dyslipidemia is a major risk factor known to be associated with diabetes and cardiovascular diseases. This study determined the frequency of lipid abnormalities among...  相似文献   
7.
Decision support systems that help physicians are becoming a very important part of medical decision making. They are based on different models and the best of them are providing an explanation together with an accurate, reliable, and quick response. One of the most viable among models are decision trees, already successfully used for many medical decision-making purposes. Although effective and reliable, the traditional decision tree construction approach still contains several deficiencies. Therefore we decided to develop and compare several decision support models using four different approaches. We took statistical analysis, a MtDeciT, in our laboratory developed tool for building decision trees with a classical method, the well-known C5.0 tool and a self-adapting evolutionary decision support model that uses evolutionary principles for the induction of decision trees. Several solutions were evolved for the classification of metabolic and respiratory acidosis (MRA). A comparison between developed models and obtained results has shown that our approach can be considered as a good choice for different kinds of real-world medical decision making.Art (from Latin ars meaning skill) is the skill in doing or performing that is attained by study, practice, or observation  相似文献   
8.
9.
The pulmonary delivery of nanoparticles (NPs) is a promising approach in nanomedicine. For the efficient and safe use of inhalable NPs, understanding of NP interference with lung surfactant metabolism is needed. Lung surfactant is predominantly a phospholipid substance, synthesized in alveolar type II cells (ATII), where it is packed in special organelles, lamellar bodies (LBs). In vitro and in vivo studies have reported NPs impact on surfactant homeostasis, but this phenomenon has not yet been sufficiently examined. We showed that in ATII-like A549 human lung cancer cells, silica-coated superparamagnetic iron oxide NPs (SiO2-SPIONs), which have a high potential in medicine, caused an increased cellular amount of acid organelles and phospholipids. In SiO2-SPION treated cells, we observed elevated cellular quantity of multivesicular bodies (MVBs), organelles involved in LB biogenesis. In spite of the results indicating increased surfactant production, the cellular quantity of LBs was surprisingly diminished and the majority of the remaining LBs were filled with SiO2-SPIONs. Additionally, LBs were detected inside abundant autophagic vacuoles (AVs) and obviously destined for degradation. We also observed time- and dose-dependent changes in mRNA expression for proteins involved in lipid metabolism. Our results demonstrate that non-cytotoxic concentrations of SiO2-SPIONs interfere with surfactant metabolism and LB biogenesis, leading to disturbed ability to reduce hypophase surface tension. To ensure the safe use of NPs for pulmonary delivery, we propose that potential NP interference with LB biogenesis is obligatorily taken into account.  相似文献   
10.
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