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91.
Sodium intake is high in Lebanon, a country of the Middle East region where rates of cardiovascular diseases are amongst the highest in the world. This study examines salt-related knowledge, attitude and self-reported behaviors amongst adult Lebanese consumers and investigates the association of socio-demographic factors, knowledge and attitudes with salt-related behaviors. Using a multicomponent questionnaire, a cross-sectional study was conducted in nine supermarkets in Beirut, based on systematic random sampling (n = 442). Factors associated with salt-related behaviors were examined by multivariate regression analysis. Specific knowledge and attitude gaps were documented with only 22.6% of participants identifying processed foods as the main source of salt, 55.6% discerning the relationship between salt and sodium, 32.4% recognizing the daily limit of salt intake and 44.7% reporting being concerned about the amount of salt in their diet. The majority of participants reported behavioral practices that increase salt intake with only 38.3% checking for salt label content, 43.7% reporting that their food purchases are influenced by salt content and 38.6% trying to buy low-salt foods. Knowledge, attitudes and older age were found to significantly predict salt-related behaviors. Findings offer valuable insight on salt-related knowledge, attitude and behaviors in a sample of Lebanese consumers and provide key information that could spur the development of evidence-based salt-reduction interventions specific to the Middle East.  相似文献   
92.
BackgroundIdentifying patients with heart failure (HF) who are most at risk of readmission permits targeting adapted interventions. The use of administrative data enables regulators to support the implementation of such interventions.Methods and ResultsIn a French nationwide cohort of patients aged 65 years or older, surviving an index hospitalization for HF in 2015 (N = 70,657), we studied HF readmission predictors available in administrative data, distinguishing HF severity from overall morbidity and taking into account the competing mortality risk, over a 1-year follow-up period. We also computed cumulative incidences and daily rates of HF readmission for patient groups defined according to HF severity and overall morbidity. Of the patients, 31.8% (n = 22,475) were readmitted at least once for HF, and 17.6% (n = 12,416) died without any readmission for HF. HF severity and overall morbidity were the strongest readmission predictors were the strongest readmission predictors (subdistribution hazard ratios 2.66 [95% CI: 2.52–2.81] and 1.37 [1.30–1.45], respectively, when comparing extreme categories). Overall morbidity and age were more strongly associated with the rate of death without HF readmission (cause-specific hazard ratios). The difference in observed HF readmission between patient risk groups was approximately 40% (21.9%, n = 2144/9,786 vs 60.4%, n = 618/1023).ConclusionsSegmentation of HF patients into readmission risk groups is possible by using administrative data, and it enables the targeting of preventive interventions.  相似文献   
93.
Oncogenic activation of tyrosine kinase signaling pathway is recurrent in human leukemia. To gain insight into the oncogenic process leading to acute megakaryoblastic leukemia (AMKL), we performed sequence analyses of a subset of oncogenes known to be activated in human myeloid and myeloproliferative disorders. In a series of human AMKL samples from both Down syndrome and non-Down syndrome patients, mutations were identified within KIT, FLT3, JAK2, JAK3, and MPL genes, with a higher frequency in DS than in non-DS patients. The novel mutations were analyzed using BaF3 cells, showing that JAK3 mutations were activating mutations. Finally, we report a novel constitutively active MPL mutant, MPLT487A, observed in a non-Down syndrome childhood AMKL that induces a myeloproliferative disease in mouse bone marrow transplantation assay.  相似文献   
94.
The role of humoral immunity in hepatitis C virus (HCV) infections is uncertain. Nevertheless, there is increasing evidence for neutralizing antibodies to HCV in the serum or plasma of chronically infected individuals. Immune globulins prepared by ethanol fractionation of plasma had long been considered safe until a commercial immune globulin product, Gammagard, prepared from plasma from which units containing anti-HCV had been excluded, transmitted HCV to recipients. Studies suggested that the exclusion might have removed neutralizing antibodies from the plasma and hence compromised the safety of the resulting immune globulins. In the present study, by using chimpanzees and a recently validated in vitro system based on neutralization of infectious HCV pseudoparticles, we found broadly reactive neutralizing and protective antibodies in experimental immune globulin preparations made from anti-HCV-positive donations. Neutralizing antibodies were also found in Gammagard lots made from unscreened plasma that did not transmit hepatitis C but not in Gammagard lots, which were prepared from anti-HCV-screened plasma, that did transmit hepatitis C. The results provide an explanation for the mechanism by which the safety of this product was compromised. Immune globulins made from anti-HCV-positive plasma and containing broadly reactive neutralizing antibodies may provide a method of preventing HCV infection.  相似文献   
95.
The alpha-fetoprotein gene (Afp) is a member of a multigenic family that comprises the related genes encoding albumin, alpha-albumin, and vitamin D binding protein. The biological role of this major embryonic serum protein is unknown although numerous speculations have been made. We have used gene targeting to show that AFP is not required for embryonic development. AFP null embryos develop normally, and individually transplanted homozygous embryos can develop in an AFP-deficient microenvironment. Whereas mutant homozygous adult males are viable and fertile, AFP null females are infertile. Our analyses of these mice indicate that the defect is caused by a dysfunction of the hypothalamic/pituitary system, leading to anovulation.  相似文献   
96.

PURPOSE

Targeted interventions to reduce the risk and increase the early detection of melanoma have the potential to save lives. We aimed to assess the effect of such an intervention on patient prevention behavior.

METHODS

We conducted a pilot clustered randomized controlled trial, comparing a targeted screening and education intervention with a conventional information-based campaign in 20 private surgeries in western France. In the intervention group, 10 general practitioners identified patients at elevated risk for melanoma with a validated assessment tool, the Self-Assessment Melanoma Risk Score (SAMScore), examined their skin, and counseled them using information leaflets. In the control group, 10 general practitioners displayed a poster and the leaflets in their waiting room and examined patients’ skin at their own discretion. The main outcome measures were sunbathing and skin self-examinations among patients at elevated risk, assessed 5 months later with a questionnaire.

RESULTS

Analyses were based on 173 patients. Compared with control patients, intervention patients were more likely to remember the campaign (81.4% vs 50.0%, P = .0001) and to correctly identify their elevated risk of melanoma (71.1% vs 42.1%, P = .001). Furthermore, intervention patients had higher levels of prevention behaviors: they were less likely to sunbathe in the summer (24.7% vs 40.8%, P = .048) and more likely to have performed skin self-examinations in the past year (52.6% vs 36.8%, P = .029). The intervention was not associated with any clear adverse effects, although there were trends whereby intervention patients were more likely to worry about melanoma and to consult their general practitioner again about the disease.

CONCLUSIONS

The combination of use of the SAMScore and general practitioner examination and counseling during consultations is an efficient way to promote patient behaviors that may reduce melanoma risk. Extending the duration of follow-up and demonstrating an impact on morbidity and mortality remain major issues for further research.  相似文献   
97.
Richter syndrome (RS) is an uncommon evolution of chronic lymphocytic leukaemia (CLL) with a dismal prognosis. Clinical-biological features predicting outcome and best therapeutic approach for these patients remain to be established. In this study, 128 patients with RS, including 112 diffuse large B-cell lymphoma (DLBCL)-type RS, 15 Hodgkin lymphoma (HL)-type RS, and one plasmablastic lymphoma, were identified in 11 centres of the Spanish CLL Study Group (GELLC). The median overall survival (OS) was 5·9 months for DLBCL-type RS and 30·8 months for HL-type RS. Eastern Cooperative Oncology Group Performance Status, haemoglobin level, platelet count, serum lactate dehydrogenase and β2-microglobulin levels, tumour protein p53 (TP53) abnormalities in the CLL clone concomitant to RS, number of prior therapies, and clonal relationship between CLL and RS, were associated with OS in patients with DLBCL-type RS. A platelet count of <100 × 109/l, prior CLL therapy (0 vs. ≥1), and presence of TP53 alterations maintained an independent prognostic impact in the multivariate analysis. Patients without any of these factors had a better clinical outcome, with a median OS of 75·3 months, while patients with one or two or more of these factors presented a median OS of 25·5 and 3 months, respectively. Although OS of patients with RS is generally poor, a proportion of patients achieved prolonged survival. Treatment of RS remains a medical need, and further therapeutic approaches with novel therapies are warranted.  相似文献   
98.
Progress in retinal-cell therapy derived from human pluripotent stem cells currently faces technical challenges that require the development of easy and standardized protocols. Here, we developed a simple retinal differentiation method, based on confluent human induced pluripotent stem cells (hiPSC), bypassing embryoid body formation and the use of exogenous molecules, coating, or Matrigel. In 2 wk, we generated both retinal pigmented epithelial cells and self-forming neural retina (NR)-like structures containing retinal progenitor cells (RPCs). We report sequential differentiation from RPCs to the seven neuroretinal cell types in maturated NR-like structures as floating cultures, thereby revealing the multipotency of RPCs generated from integration-free hiPSCs. Furthermore, Notch pathway inhibition boosted the generation of photoreceptor precursor cells, crucial in establishing cell therapy strategies. This innovative process proposed here provides a readily efficient and scalable approach to produce retinal cells for regenerative medicine and for drug-screening purposes, as well as an in vitro model of human retinal development and disease.Irreversible blindness caused by retinal diseases, such as inherited retinopathies, age-related macular degeneration (AMD), or glaucoma, is mainly due to the impairment or loss of function of photoreceptor cells, supporting retinal pigmented epithelium (RPE) or retinal ganglion cells (RGCs). Rescuing the degenerated retina is a major challenge for which specific cell replacement is one of the most promising approaches (1, 2). Pluripotent stem cells, like human embryonic stem cells (hESCs) or induced pluripotent stem cells (hiPSCs), have the ability to be expanded indefinitely in culture and could be used as an unlimited source of retinal cells for the treatment of retinal degenerative diseases (3, 4). Several publications have indicated that hESCs and hiPSCs can be differentiated into RPE cells spontaneously after fibroblast growth factor (FGF) 2 removal (57) or by different floating aggregate methods (811). Concerning neural retinal cells, a growing body of convergent data has demonstrated the ability of hESCs or hiPSCs to be committed into the neural retinal lineage and further differentiated into cells expressing photoreceptor markers (1215). Recent innovative approaches using 3D cultures from embryoid bodies (EBs) of hESCs or hiPSCs allowed the self-formation of optic cup (OC) structures (16) or the generation of optic vesicle (OV)-like structures (17), depending on the addition of exogenous molecules and different substrates used. These protocols require multiple steps and trained handling, which are not always compatible with the manufacturing process for therapeutic approach or drug screening that need a large-scale production of cells of interest. Therefore, very simple and reliable approaches minimizing the use of exogenous molecules should be developed to generate hESCs or hiPSC-derived retinal cells.In the present study, we report a new retinal differentiation process using confluent hiPSCs, without cell clumps or EB formation and in the absence of Matrigel or serum. We demonstrate that integration-free hiPSCs derived from adult human dermal fibroblasts (AHDFs) cultured in proneural medium can simultaneously generate RPE cells and self-forming neural retinal (NR)-like structures within 2 wk and that, when switched to floating cultures, structures containing retinal progenitor cells (RPCs) can differentiate into all retinal cell types, including RGCs and precursors of photoreceptors, needed for therapeutic applications.  相似文献   
99.

Background

Fetuses exposed to angiotensin-converting enzyme inhibitors or angiotensin receptor antagonists during the second and/or third trimesters of gestation are at high risk of developing severe complications. They consist in fetal hypotension, and anuria/oligohydramnios leading to Potter sequence, frequently associated with hypocalvaria. Most fetuses die during the pre- or postnatal period, whereas others recover normal or subnormal renal function. However, the secondary occurrence of renal failure or hypertension has been reported in children after apparent complete recovery.

Methods

In this context, we analyzed renal lesions in 14 fetus/neonates who died soon after exposure to renin-angiotensin-system (RAS) blockers. Our objective was to determine the causes for the persistence or the secondary occurrence of renal complications reported in some of the survivors.

Results

As previously described, renal tubular dysgenesis is usually observed. Additional lesions, such as thickening of the muscular wall of arterioles and interlobular arteries, glomerular cysts, and interstitial fibrosis, develop early during fetal life.

Conclusion

We suggest that renal lesions that develop before birth may persist after withdrawal of the causative drugs and normalization of blood and renal perfusion pressure. Their persistence could explain the severe long-term outcome of some of these patients. Long-term study of children exposed to RAS blockers during fetal life is strongly recommended.  相似文献   
100.
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