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We studied the effect of low levels of vitamin B12 and folic acid, alone or combined, on cognitive performance in a population-based sample of 698 older adults (mean age = 68.7 years). No evidence was found for a vitamin-related memory deficit, but research participants with low levels of vitamin B12 exhibited reduced information processing speed relative to participants with normal vitamin B12 levels.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate the specificity and sensitivity of the real-time quantitative PCR method for fetal gender determination in early pregnancy. METHODS: Blood samples were collected from 46 pregnant women prior to amniocentesis. DNA was extracted from maternal plasma using a QIAmp DNA Blood Mini Kit. DNA samples were subjected to real-time quantitative PCR amplification of SRY (as a fetus-specific marker) and beta-globin (as a marker for total plasma DNA) genes. RESULTS: The beta-globin gene sequence was detected in all samples. The SRY gene was detected in 25 of 28 plasma samples from women with male fetuses and in none of the 18 samples from women with female fetuses (sensitivity 89.2% and specificity 100%). The fetal gender was correctly determined in 43 (93.5%) of 46 maternal plasma samples. The concentration of the beta-globin gene ranged from 161 to 25,568 genome-equivalents (GE)/mL (median 1051.1), while the concentration of the SRY gene ranged from 5 to 166 GE/mL (median 27.4). The percentage of free fetal DNA ranged from 0.1% to 46.1% (median 2.0%). CONCLUSION: Amplification of fetal DNA from maternal plasma by real-time quantitative PCR is a promising method for fetal sex determination in early pregnancy. However, further studies are necessary before this procedure can be included into a clinical routine.  相似文献   
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Introduction: Amyotrophic Lateral Sclerosis (ALS) is a progressive, incurable neurodegenerative disease that targets motoneurons. Cell-based therapies have generated widespread interest as a potential therapeutic approach but no conclusive results have yet been reported either from pre-clinical or clinical studies.

Areas covered: This is an integrated review of pre-clinical and clinical studies focused on the development of cell-based therapies for ALS. We analyze the biology of stem cell treatments and results obtained from pre-clinical models of ALS and examine the methods and the results obtained to date from clinical trials. We discuss scientific, clinical, and ethical issues and propose some directions for future studies.

Expert opinion: While data from individual studies are encouraging, stem-cell-based therapies do not yet represent a satisfactory, reliable clinical option. The field will critically benefit from the introduction of well-designed, randomized and reproducible, powered clinical trials. Comparative studies addressing key issues such as the nature, properties, and number of donor cells, the delivery mode and the selection of proper patient populations that may benefit the most from cell-based therapies are now of the essence. Multidisciplinary networks of experts should be established to empower effective translation of research into the clinic.  相似文献   

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Purpose

The goal of this study was to evaluate clinical outcomes and patient-reported outcomes (PROs) over 12 months in patients with relapsing multiple sclerosis (RMS) who switched from glatiramer acetate (GA) to delayed-release dimethyl fumarate (DMF) 240 mg BID after suboptimal response to GA in real-world clinical practice.

Methods

The RESPOND (Effectiveness of DMF and Its Impact on PROs in Suboptimal GA Responders With RMS) study was a Phase IV, prospective, multicenter, open-label, single-arm, 12-month observational trial. The study was conducted in the United States at 63 sites between August 2013 and February 2016. Patients diagnosed with RMS who experienced a suboptimal response to GA (defined as perceived suboptimal efficacy, intolerance, or poor adherence to GA) were eligible for enrollment. DMF treatment was initiated within 60 days of enrollment. The primary objective was to estimate the annualized relapse rate (ARR) at 12 months based on data collected from medical records and compare it with the 12 months before DMF initiation. Secondary objectives of the study included assessing the change in PRO scores from baseline to 12 months; PROs were recorded before and at 6 and 12 months after DMF initiation.

Findings

Of the 318 patients included in the analysis population, 247 (78%) completed treatment. Mean (SD) time on GA treatment before switching to DMF was 51.3 months (49.1 months). The ARR (95% CI) reported for the 12 months before DMF initiation was 0.49 (0.42–0.57) compared with 0.11 (0.07–0.17) at 12 months after DMF initiation, representing a 78% reduction in ARR (P < 0.0001). Statistically significant improvements from baseline were observed for multiple PROs, including the 36-item Short Form Health Survey physical and mental component summaries (P = 0.0201 and P = 0.0014, respectively), the 5-item Modified Fatigue Impact Scale (P = 0.0002), the 14-item Treatment Satisfaction Questionnaire for Medication (P < 0.0001), and the 7-item Beck Depression Inventory (P = 0.0117).

Implications

DMF may be an effective treatment option in patients with RMS who experience a suboptimal response to GA. The results should be interpreted with caution due to the observational nature of the study and the lack of a control group. Other limitations of the study include a potential bias due to regression to the mean and lack of randomization. ClinicalTrials.gov identifier: NCT01903291.  相似文献   
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The prevalence of Helicobacter pylori (HP) infection increases with age worldwide. Unlike in younger patients, the presentation of peptic disease in the elderly population is subtle and atypical, and thus leads to a delay of diagnosis. Due to comorbidities and advanced age, it results in increased complications, morbidity and mortality. Bleeding and perforation are frequent complications and therefore peptic ulcer in adult patients represents a serious disease. The relationship between the infection caused by HP and the use of non-steroidal anti-inflammatory drugs (NSAID) in the pathogenesis of peptic ulcer disease is still controversial. However these two factors, independently or in synergy, represent the principal cause of peptic ulcer development in the adult population. In patients diagnosed with peptic ulcer caused by HP, more than half take medications containing aminosalicylic acid. Helicobacter pylori infection in elderly NSAID users is associated with an increased ulcer incidence, but not with an increased prevalence of upper digestive tract bleeding. Helicobacter pylori and NSAID consumption are independent and unrelated risk factors for upper gastrointestinal tract bleeding. Eradication of HP is recommended before the initiation of a long-term aspirin administration in elderly patients. Low aspirin dosages are associated with a high risk of ulcer bleeding. The risk of upper gastrointestinal bleeding in elderly patients is significantly higher in the cases of acute abuse of NSAIDs relative to its chronic use. The simultaneous use of NSAID or aspirin and selective serotonin reuptake inhibitors--antidepressants, increases the risk of upper gastrointestinal bleeding. Peptic ulcer disease in the adult population, if combined with old age, presence of serious and/or life- threatening diseases, as well as repeated ulcer bleedings, shows a high mortality rate.  相似文献   
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Interaction between autoreactive immune cells and astroglia is an important part of the pathologic processes that fuel neurodegeneration in multiple sclerosis. In this inflammatory disease, immune cells enter into the central nervous system (CNS) and they spread through CNS parenchyma, but the impact of these autoreactive immune cells on the activity pattern of astrocytes has not been defined. By exploiting naïve astrocytes in culture and CNS-infiltrated immune cells (CNS IICs) isolated from rat with experimental autoimmune encephalomyelitis (EAE), here we demonstrate previously unrecognized properties of immune cell–astrocyte interaction. We show that CNS IICs but not the peripheral immune cell application, evokes a rapid and vigorous intracellular Ca2+ increase in astrocytes by promoting glial release of ATP. ATP propagated Ca2+ elevation through glial purinergic P2X7 receptor activation by the hemichannel-dependent nucleotide release mechanism. Astrocyte Ca2+ increase is specifically triggered by the autoreactive CD4+ T-cell application and these two cell types exhibit close spatial interaction in EAE. Therefore, Ca2+ signals may mediate a rapid astroglial response to the autoreactive immune cells in their local environment. This property of immune cell–astrocyte interaction may be important to consider in studies interrogating CNS autoimmune disease.  相似文献   
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We operated on a 34-year-old man with a metastatic tumor that extended from the tricuspid valve to the pulmonary valve and obstructed the right ventricle inflow and outflow tracts. The tumor was removed with preservation of the tricuspid valve. Additional chemotherapy was carried out according to the BEPO (etoposid, eisplatin, bleomycin, vincritin) scheme. Histology revealed metastasis of a choriocarcinoma originating from the right testis. Computed tomography performed after 6 months detected no metastases in the lungs. Magnetic resonance imaging showed a thickened right ventricle free wall and apex. The patient is doing well 18 months postoperatively.  相似文献   
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