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81.
Prenatal heart valve interventions aiming at the early and systematic correction of congenital cardiac malformations represent a promising treatment option in maternal-fetal care. However, definite fetal valve replacements require growing implants adaptive to fetal and postnatal development. The presented study investigates the fetal implantation of prenatally engineered living autologous cell-based heart valves. Autologous amniotic fluid cells (AFCs) were isolated from pregnant sheep between 122 and 128 days of gestation via transuterine sonographic sampling. Stented trileaflet heart valves were fabricated from biodegradable PGA-P4HB composite matrices (n = 9) and seeded with AFCs in vitro. Within the same intervention, tissue engineered heart valves (TEHVs) and unseeded controls were implanted orthotopically into the pulmonary position using an in-utero closed-heart hybrid approach. The transapical valve deployments were successful in all animals with acute survival of 77.8% of fetuses. TEHV in-vivo functionality was assessed using echocardiography as well as angiography. Fetuses were harvested up to 1 week after implantation representing a birth-relevant gestational age. TEHVs showed in vivo functionality with intact valvular integrity and absence of thrombus formation. The presented approach may serve as an experimental basis for future human prenatal cardiac interventions using fully biodegradable autologous cell-based living materials.  相似文献   
82.
Little is known on growth, growth hormone (GH) levels and GH treatment in patients with Ellis-van Creveld syndrome (EvC). The aim of the present study was to assess growth, growth hormone status and the possible effectiveness of GH treatment in literature and in a small series of EvC patients. A review of literature indicated retarded growth for most EvC patients (-2 to -4.5 SDS) and minimal data on GH levels or treatment which did not allow any conclusion. We studied eight EvC patients, seven of whom were treated with GH. Four were GH deficient (GHD) and four were GH sufficient. In all patients treated with GH, first year growth velocity increased. In three of the four GHD and in one GH-sufficient patient a gain in height SDS was noted. In the present small EvC series GHD occurred more often than expected. Patient acquisition through the Growth Hormone Database will have caused a significant bias, but the present results indicate that GH treatment may improve growth in at least some patients with EvC. Therefore we conclude that EvC patients may benefit from being tested for GHD and, if indicated, treated. In addition a prospective study to evaluate GH status and linear growth in patients with EvC as well as the potential effectiveness of GH treatment is warranted.  相似文献   
83.
About 15% of sporadic gastrointestinal and endometrial tumors show the microsatellite instability (MSI) phenotype because of loss of DNA mismatch repair (MMR) function. The incidence of MSI in tumors of the central nervous system still remains controversial. Previous studies reported a particular high frequency of MSI (approximately 25%) in young patients suffering from high-grade gliomas. Based on these data and the fact that in different tumor entities MMR deficiency defines a subgroup of tumors with distinct pathogenesis and particular clinicopathological features that may have impact on prognosis and therapy, we screened 624 gliomas from 71 young and 553 adult patients for MMR deficiency by MSI analysis using three highly sensitive diagnostic markers. Alterations of MMR protein expression was examined by immunohistochemistry. A malignant glioma from an adult patient displayed MSI and concomitant loss of nuclear MSH2 and MSH6 protein expression (0.16%; 1/619). No evidence for MSI or loss of MMR protein expression was observed in 71 gliomas from young patients (0%; 0/71) including 41 high-grade astrocytic tumors. Overall, we observed a much lower incidence of MSI among high-grade pediatric gliomas than initially reported and suggest that MMR deficiency does not play a major role in the pathogenesis of glial neoplasms.  相似文献   
84.
According to the Banff guidelines for renal transplants, pure endothelialitis without any tubulointerstitial infiltrates (with the Banff components v?≥?1, i0, t0) has to be called acute cellular rejection (ACR). The pathophysiology of this rare lesion abbreviated as v_only is currently unclear, as well as its clinical, serological, and prognostic implications. Therefore, we conducted this retrospective comparative study. We compared all 23 biopsies with v_only from Hannover Medical School between 2003 and 2010 with 23 matched biopsies with the Banff components v?≥?1, i?≥?1, and t?≥?1 (v_plus) and 23 biopsies with v0, i0, and t0 (v0i0t0). Serological (available in 10, 11, and 14 patients, respectively), histological, and clinical data were compared. Of all biopsies, 0.4 % had findings of v_only. v_only, v_plus, and v0i0t0 only showed minimal differences in the Banff components apart from the cohort-defining components. Endothelialitis in v_only more frequently involved the arcuate arteries than the smaller preglomerular vessels compared to v_plus and vice versa. Combining histopathological data and serological data, v_only more frequently showed criteria for acute humoral rejection than v0i0t0 (albeit not persistent after the Bonferroni–Holm correction in pairwise comparisons), while there was no difference between v_only and v_plus. No difference could be demonstrated regarding clinical presentation at biopsy or outcome. Our results show minimal differences regarding clinical presentation, outcome, and histological features between v_only and v_plus. Patients with v_only should be thoroughly investigated for evidence of acute humoral rejection.  相似文献   
85.
BackgroundThe psychological health in obese women during pregnancy has been poorly studied.ObjectiveTo compare levels of anxiety and depressed mood during pregnancy in obese versus normal-weight women.Methods63 obese pregnant women and 156 normal-weight controls were included prospectively before 15 weeks of gestation. Levels of state and trait anxiety and depressed mood were measured during the first, second and third trimester of pregnancy. A linear mixed-effect model with repeated measures was used to evaluate group differences.ResultsThe levels of state anxiety significantly increased from trimester 1 to trimester 3 in obese pregnant women (beta = 3.70; p = 0.007), while this parameter remained constant throughout pregnancy in normal-weight women. Levels of trait anxiety and depressed mood significantly decreased from trimester 1 to trimester 2 in controls, but not in obese pregnant women. Variables such as maternal education, ethnicity, marital state, psychological history and miscarriages, parity and smoking behaviour had significant effects on anxiety and/or depressed moods during pregnancy. Obese pregnant women show higher levels of anxiety and depressive symptomatology compared to normal-weight pregnant women.ConclusionInterventional programmes aiming at preventing the deleterious influence of maternal obesity on perinatal outcomes should include a psycho-educational program specifically tailored to this high-risk group.Key Words: Obesity, Pregnancy, Body mass index, Anxiety, Depressed mood, Psychological aspects, Obesity management  相似文献   
86.
Adaptation of the skin colour to the background light condition in the amphibian Xenopus laevis is achieved by migration of pigment granules in the skin melanophores, a process regulated by α-MSH secretion from melanotrope cells in the pituitary pars intermedia (PI). α-MSH secretion in turn, is regulated by various stimulatory and inhibitory messengers synthesized in brain nuclei, especially the hypothalamic suprachiasmatic and magnocellular nuclei and the locus coeruleus in the hindbrain.In the present study, the roles in background adaptation of nitric oxide (NO) and NO synthase (NOS) enzyme activity were evaluated. In situ, using both immunohistochemistry with anti-human brain NOS (bNOS) serum in paraffin-embedded material and using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry in cryo-sections, we showed NOS in neurons in the optic tectum and in the locus coeruleus. NADPH-d reactivity was also found in neurons in the lateral amygdala, the ventral hypothalamic nucleus and in fibers in the median eminence. Using a Western blot stained with an anti-human bNOS serum, we demonstrated a 150 kDa band in Xenopus hindbrain lysates, which is similar to the NOS protein present in the rat anterior pituitary, but which was not detectable in the lysates from both the neurointermediate and distal lobes in Xenopus. No differences in histochemical staining pattern or on Western blotting were observed between animals adapted to a black or a white background.Paraffin sections of the endocrine PI and pars distalis did not reveal bNOS-like immunoreactivity. NADPH-d reactivity was observed in the endothelia of this gland. However, using a new procedure of thin cryo-sections of pituitary neurointermediate lobes, we observed bNOS-immunoreactive fibers as well as cyclic 3′,5′ guanosine monophosphate (cGMP)-accumulating fibers in the PI.The PI may be regulated by NOergic neurons from higher brain centers. The possibility that NOergic neurons in the locus coeruleus are involved in the innervation of the PI needs further investigation. The latter neurons are probably not noradrenergic because double labeling studies show no co-localization of NADPH-d reactivity and tyrosine hydroxylase immunoreactivity in locus coeruleus neurons.  相似文献   
87.
Apoptosis (programmed cell death) plays important roles in many facets of normal mammalian physiology. Host-pathogen interactions have provided evolutionary pressure for apoptosis as a defense mechanism against viruses and microbes, sometimes linking apoptosis mechanisms with inflammatory responses through NFκB induction. Proteins involved in apoptosis and NFκB induction commonly contain evolutionarily conserved domains that can serve as signatures for identification by bioinformatics methods. Using a combination of public (NCBI) and private (RIKEN) databases, we compared the repertoire of apoptosis and NFκB-inducing genes in humans and mice from cDNA/EST/genomic data, focusing on the following domain families: (1) Caspase proteases; (2) Caspase recruitment domains (CARD); (3) Death Domains (DD); (4) Death Effector Domains (DED); (5) BIR domains of Inhibitor of Apoptosis Proteins (IAPs); (6) Bcl-2 homology (BH) domains of Bcl-2 family proteins; (7) Tumor Necrosis Factor (TNF)-family ligands; (8) TNF receptors (TNFR); (9) TIR domains; (10) PAAD (PYRIN; PYD, DAPIN); (11) nucleotide-binding NACHT domains; (12) TRAFs; (13) Hsp70-binding BAG domains; (14) endonuclease-associated CIDE domains; and (15) miscellaneous additional proteins. After excluding redundancy due to alternative splice forms, sequencing errors, and other considerations, we identified cDNAs derived from a total of 227 human genes among these domain families. Orthologous murine genes were found for 219 (96%); in addition, several unique murine genes were found, which appear not to have human orthologs. This mismatch may be due to the still fragmentary information about the mouse genome or genuine differences between mouse and human repertoires of apoptotic genes. With this caveat, we discuss similarities and differences in human and murine genes from these domain families.  相似文献   
88.
Allergen extracts have been used for diagnosis and treatment of allergy for around 100 years. During the second half of 20th century, the notion increasingly gained foothold that accurate standardization of such extracts is of great importance for improvement of their quality. As a consequence, manufacturers have implemented extensive protocols for standardization and quality control. These protocols have overall IgE-binding potencies as their focus. Unfortunately, each company is using their own in-house reference materials and their own unique units to express potencies. This does not facilitate comparison of different products. During the last decades, most major allergens of relevant allergen sources have been identified and it has been established that effective immunotherapy requires certain minimum quantities of these allergens to be present in the administered maintenance dose. Therefore, the idea developed to introduce major allergens measurements into standardization protocols. Such protocols based on mass units of major allergen, quantify the active ingredients of the treatment and will at the same time allow comparison of competitor products. In 2001, an EU funded project, the CREATE project, was started to support introduction of major allergen based standardization. The aim of the project was to evaluate the use of recombinant allergens as reference materials and of ELISA assays for major allergen measurements. This paper gives an overview of the achievements of the CREATE project.  相似文献   
89.
The effect of successful ventricular assist device (VAD) implantation on neurocognitive function in terminal heart failure is uncertain. Additionally, the different impact of continuous versus pulsatile blood flow devices is unknown. A total of 29 patients (mean age 53 years), surviving implantation of a ventricular assist device as bridge to transplantation were prospectively followed (continuous flow: Micromed DeBakey, n = 11; pulsatile flow: Thoratec and Novacor, n = 18). Normative data were obtained in 40 age- and sex-matched healthy subjects (mean age 54 years). Neurocognitive function was objectively measured by means of cognitive P300 auditory evoked potentials before operation (baseline), at intensive care unit (ICU) discharge, and at the 8-week and 12-week follow-up. Before implantation of the VAD, cognitive P300 evoked potentials were impaired (prolonged) compared with age- and sex-matched healthy subjects (p < 0.001). After successful VAD implantation, P300 evoked potentials markedly improved compared with before operation (ICU discharge, p = 0.007; 8-week follow-up, p = 0.022; 12-week follow-up, p < 0.0001). Importantly, there was no difference between continuous and pulsatile VADs (before operation, p = 0.676; ICU discharge, p = 0.736; 8-week follow-up, p = 0.911 and 12-week follow-up, p = 0.397; respectively). Nevertheless, P300 peak latencies did not fully normalize at 12-week follow-up compared with healthy subjects (p = 0.012). Successful VAD implantation improves neurocognitive impairment in patients with terminal heart failure. Importantly, this effect is independent of the type of VAD (pulsatile vs. continuous blood flow).  相似文献   
90.
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