CFH, ELOVL4, PLEKHA1 and LOC387715 genes and susceptibility to age-related maculopathy: AREDS and CHS cohorts and meta-analyses

Age-related maculopathy (ARM) is an important cause of visual impairment in the elderly population. It is of crucial importance to identify genetic factors and their interactions with environmental exposures for this disorder. This study was aimed at investigating the CFH, ELOVL4, PLEKHA1 and LOC387715 genes in independent cohorts collected using different ascertainment schemes. The study used a case-control design with subjects originally recruited through the Cardiovascular Health Study (CHS) and the Age-Related Eye Disease Study (AREDS). CFH was significantly associated with ARM in both cohorts (P相似文献   

Biomimetic approach to cardiac tissue engineering: oxygen carriers and channeled scaffolds

We report that the functional assembly of engineered cardiac muscle can be enhanced by oxygen supply provided by mechanisms resembling those in normal vascularized tissues. To mimic the capillary network, cardiomyocytes and fibroblasts isolated from the neonatal rat hearts were cultured on a highly porous elastomer with a parallel array of channels that were perfused with culture medium. To mimic oxygen supply by hemoglobin, culture medium was supplemented with a perfluorocarbon (PFC) emulsion; constructs perfused with unsupplemented culture medium served as controls. In PFC-supplemented medium, the decrease in the partial pressure of oxygen in the aqueous phase was only 50% of that in control medium (28 mmHg vs. 45 mmHg between the construct inlet and outlet at a flow rate of 0.1 mL/min). Consistently, constructs cultivated in the presence of PFC contained higher amounts of DNA and cardiac markers (troponin I, connexin-43) and had significantly better contractile properties as compared to control constructs. In both groups, electron microscopy revealed open channels and the presence of cells at the channel surfaces as well as within constructs. Improved properties of cardiac constructs could be correlated with the enhanced supply of oxygen to the cells, by a combined use of channeled scaffolds and PFC.     

Long-term ethanol consumption and macrocytosis: diagnostic and pathogenic implications

Although excessive alcohol consumption is known to elevate the mean cell volume (MCV) of erythrocytes, the relationships among the intensity of ethanol exposure, the generation of abnormal red blood cell indices, and the underlying pathogenic mechanisms have remained unclear. The authors examined 105 alcoholics with a wide range of ethanol consumption (40-500 g of ethanol/day), 62 moderate drinkers (mean consumption 1-40 g/day), and 24 abstainers, who underwent detailed interviews, measurements of blood cell counts, markers of liver status, and circulating antibodies against ethanol-derived protein modifications. Follow-up information was collected from healthy volunteers with detailed records on drinking habits. Data from the NORIP project for laboratory parameters in apparently healthy moderate drinkers or abstainers (n = 845) were used for reference interval comparisons. The highest MCV (P < 0.001) and mean cell hemoglobin (MCH) (P < 0.01) occurred in the alcoholics. However, the values in the moderate drinkers also responded to ethanol intake such that the upper normal limit for MCV based on the data from moderate drinkers was 98 fl, as compared with 96 fl from abstainers. Follow-up cases with carefully registered drinking habits showed parallel changes in MCV and ethanol intake. Anti-adduct IgA and IgM against acetaldehyde-induced protein modifications were elevated in 94% and 64% of patients with high MCV, respectively, the former being significantly less frequent in the alcoholics with normal MCV (63%) (P < 0.05). The data indicate dose-related responses in red blood indices upon chronic ethanol consumption, which may also be reflected in reference intervals for hematological parameters in health care. Generation of immune responses against acetaldehyde-modified erythrocyte proteins may be associated with the appearance of such abnormalities.     

Identification of six new alleles at the FUT1 and FUT2 loci in ethnically diverse individuals with Bombay and Para-Bombay phenotypes

BACKGROUND: The Bombay and para-Bombay phenotypes arise from mutations of the FUT1 gene that silence the gene or affect the efficiency of the encoded 2-alpha-fucosyltransferase. Samples from seven individuals of different geographic backgrounds whose red blood cells had an apparent Bombay or para-Bombay phenotype were investigated. Among these, novel FUT1 and FUT2 alleles were identified. STUDY DESIGN AND METHODS: Standard serologic techniques were used. Genomic DNA was sequenced with primers that amplified the coding sequence of FUT1 and the related secretor gene, FUT2. Routine ABO genotyping analysis was performed. RESULTS: Five new FUT1 alleles were identified that silenced FUT1 or weakened alpha2FucT1 activity. These were 35C>T, 269G>T (Ala11Val, Gly89Val); 421A>G (Trp140Stop); 538C>T, 1089T>G (Gln180Stop, Ala363Ala); 689A>C (Gln230Pro); and 917C>T (Thr305Ile). In addition, both homozygosity and heterozygosity for the previously reported mutation, 826C>T (Gln276Stop), were observed. Four of seven samples were homozygous for the silencing mutation 428A in FUT2. One new FUT2 allele was identified: 278C>T, 357C>T (Ala93Val, Asn119Asn). CONCLUSIONS: These results add to the growing database of apparently sporadic and random mutations in the FUT1 gene and confirm previous reports regarding the lack of ethnic bias. In contrast, our data reinforce the apparent maintenance of the common nonsecretor FUT2 alleles in the population.     

Long-term survival in refractory acute myeloid leukemia after sequential treatment with chemotherapy and reduced-intensity conditioning for allogeneic stem cell transplantation

A sequential regimen of chemotherapy, reduced-intensity conditioning (RIC) for allogeneic stem cell transplantation (SCT), and prophylactic donor lymphocyte transfusion (pDLT) was studied in 103 patients with refractory acute myeloid leukemia (AML). According to published criteria, refractoriness was defined by primary induction failure (PIF; n = 37), early (n = 53), refractory (n = 8), or second (n = 5) relapse. Chemotherapy consisted of fludarabine (4 x 30 mg/m(2)), cytarabine (4 x 2 g/m(2)), and amsacrine (4 x 100 mg/m(2)), followed 4 days later by RIC, comprising 4 Gy total body irradiation (TBI), cyclophosphamide, and antithymocyte globulin. Patients without graft-versus-host disease (GvHD) at day +120 received pDLT in escalating doses. Patients' median age was 51.8 years. Before conditioning, 99 patients had active disease, 3 were aplastic, 1 was in second complete remission (CR2). Forty-one patients had family donors, 62 had unrelated donors. With a 25-month median follow-up, overall survival (OS) at 1, 2, and 4 years was 54%, 40%, and 32%; the respective leukemia-free survival (LFS) was 47%, 37%, and 30%. Patients with PIF showed a 2-year OS of 62.5%. OS was 87% in 17 patients receiving pDLT. One-year cumulative incidence of leukemic death and non-relapse-mortality was 28.7% and 17.2%. In a multivariate analysis, more than 2 courses of prior chemotherapy were the strongest predictor for poor outcome (P = .007; HR = 3.01 [OS]; P = .002; HR = 3.25 [LFS]). These results indicate a high activity of the regimen in refractory AML.     

Quantitative sensory testing in children with migraine: preliminary evidence for enhanced sensitivity to painful stimuli especially in girls

Recent studies showed an enhanced general sensitivity to painful stimuli in adult migraineurs during as well as between attacks. Yet, the influence of a prolonged pain history and potential sex differences has not been studied. We used quantitative sensory testing to examine 25 children with migraine between attacks and 28 controls (age 9-15). The assessment included the measurement of heat and mechanical pain thresholds as well as measures of perceptual sensitization in response to repetitive (mechanical) or tonic (thermal) noxious stimulation at both trigeminal and thenar sites. In addition, the mother was either present or absent during the measurements. Heat pain thresholds were not significantly different between the two groups. However, the child migraineurs showed significantly lower mechanical pain thresholds. Children and especially girls with migraine displayed significantly more sensitization to a tonic heat stimulus at the trigeminal site when the mother was present. The migraineurs also showed a trend towards higher sensitization ratings for mechanical stimuli. Overall, heat pain thresholds were significantly higher in the presence of the mother. In the migraine group only, mechanical pain thresholds were significantly higher when the mother was present. To summarize, an enhanced sensitivity to painful stimuli can already be observed in children suffering from migraine for an average duration of 4.4 years. This may be the result of sensitization in nociceptive pain pathways caused by frequent pain experiences. Girls with migraine were more prone to such sensitization, which may increase their risk for continuing to suffer from migraine throughout adulthood.     

A change in the Dutch Directive on Medical Research Involving Human Subjects strongly increases the number of eligible intensive care patients: an observational study

Objectives To determine the effect of a change in the “Dutch Directive on Medical Research Involving Human Subjects” (DD) on the number of eligible intensive care unit (ICU) patients for medical research. In addition, we determined how family members experience their role as acting representative for giving informed consent, and in turn whether patients feel their representatives would do well representing them.Design and setting Prospective observational study in three Dutch ICUs.Participants 714 consecutive ICU patients. Analysis was restricted to 211 patients who were incapacitated for more than 24 h after ICU admission.Measurements and results The old DD left 45.5% of patients without a legal representative; with the new DD this figure declines to 8.1%. Older age was significantly associated with the impossibility of obtaining informed consent in the old DD; after the change there was no effect of age. The median grade of confidence that representatives had in giving informed consent for incapacitated patients was 8.0 (IQR 7.0–9.0) on a scale from 0 to 10. Patients gave an equal median grade to their representatives.Conclusion When patients' adult children are not legally allowed to give informed consent, older patients are excluded from medical research, causing selection bias. The change in the DD has increased the number of surrogates allowed to give informed consent. Representatives felt very confident in their ability to represent the patients. In turn patients were equally confident that their representatives were able to represent them.This article is discussed in the editorial available at:     

G protein-coupled receptor for asthma susceptibility associates with respiratory distress syndrome

BACKGROUND: Respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD) have some common features with asthma. AIM: To study whether G protein-coupled receptor for asthma susceptibility (GPRA) contributes to RDS or BPD. METHODS: A haplotype association study was performed in a case-control setting of 521 Finnish infants (including 176 preterm neonates with RDS and 37 with BPD). Immunoreactivity of GPRA isoforms A and B was determined in pulmonary samples of fetuses, term infants and preterm infants with RDS or BPD. GPRA mRNA expression was determined by quantitative real-time polymerase chain reaction (PCR) in samples from nasal respiratory epithelium of adults, term infants and preterm infants. RESULTS: In infants with RDS born at 32-35 weeks of gestation, GPRA haplotype H1 was significantly underrepresented in RDS, whereas haplotype H4/H5 was associated with an increased risk. As in asthma, GPRA B isoform was induced in bronchial smooth muscle cells in RDS and BPD. In nasal respiratory epithelium, relative GPRA mRNA expression was strong in adults, weak in preterm and slightly higher in term samples. CONCLUSIONS: The results suggest that near-term RDS and asthma share the same susceptibility and protective GPRA haplotypes. Altered GPRA expression may play a role in the pathogenesis of RDS and BPD in preterm infants.