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151.
Attention deficit/hyperactivity disorder (ADHD) is one of the most common child psychiatric disorders, and is often treated with stimulant medication. Nonpharmacological treatments include dietary supplementation with omega-3 fatty acids, although their effectiveness remains to be shown conclusively. In this study, we investigated the effects of dietary omega-3 fatty acid supplementation on ADHD symptoms and cognitive control in young boys with and without ADHD. A total of 40 boys with ADHD, aged 8–14 years, and 39 matched, typically developing controls participated in a 16-week double-blind randomized placebo-controlled trial. Participants consumed 10 g of margarine daily, enriched with either 650 mg of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) each or placebo. Baseline and follow-up assessments addressed ADHD symptoms, fMRI of cognitive control, urine homovanillic acid, and cheek cell phospholipid sampling. EPA/DHA supplementation improved parent-rated attention in both children with ADHD and typically developing children. Phospholipid DHA level at follow-up was higher for children receiving EPA/DHA supplements than placebo. There was no effect of EPA/DHA supplementation on cognitive control or on fMRI measures of brain activity. This study shows that dietary supplementation with omega-3 fatty acids reduces symptoms of ADHD, both for individuals with ADHD and typically developing children. This effect does not appear to be mediated by cognitive control systems in the brain, as no effect of supplementation was found here. Nonetheless, this study offers support that omega-3 supplementation may be an effective augmentation for pharmacological treatments of ADHD (NCT01554462: The Effects of EPA/DHA Supplementation on Cognitive Control in Children with ADHD; http://clinicaltrials.gov/show/NCT01554462).  相似文献   
152.
Ligands for the NKG2D receptor are overexpressed on tumors, making them interesting immunotherapy targets. To assess the tumoricidal properties of T cells directed to attack NKG2D ligands, we engineered murine T cells with two distinct NKG2D-based chimeric antigen receptors (CARs): (i) a fusion between the NKG2D receptor and the CD3ζ chain and (ii) a conventional second-generation CAR, where the extracellular domain of NKG2D was fused to CD28 and CD3ζ. To enhance the CAR surface expression, we also engineered T cells to coexpress DAP10. In vitro functionality and surface expression levels of all three CARs was greater in BALB/c T cells than C57BL/6 T cells, indicating strain-specific differences. Upon adoptive transfer of NKG2D-CAR-T cells into syngeneic animals, we observed significant clinical toxicity resulting in morbidity and mortality. The severity of these toxicities varied between the CAR configurations and paralleled their in vitro NKG2D surface expression. BALB/c mice were more sensitive to these toxicities than C57BL/6 mice, consistent with the higher in vitro functionality of BALB/c T cells. Treatment with cyclophosphamide prior to adoptive transfer exacerbated the toxicity. We conclude that while NKG2D ligands may be useful targets for immunotherapy, the pursuit of NKG2D-based CAR-T cell therapies should be undertaken with caution.  相似文献   
153.
PURPOSE: The clinical impact of rectal compliance and sensitivity measurement is not clear. The aim of this study was to measure the rectal compliance in different patient groups compared with controls and to establish the clinical effect of rectal compliance. METHODS: Anorectal function tests were performed in 974 consecutive patients (284 men). Normal values were obtained from 24 controls. Rectal compliance measurement was performed by filling a latex rectal balloon with water at a rate of 60 ml per minute. Volume and intraballoon pressure were measured. Volume and pressure at three sensitivity thresholds were recorded for analysis: first sensation, urge, and maximal toleration. At maximal toleration, the rectal compliance (volume/pressure) was calculated. Proctoscopy, anal manometry, anal mucosal sensitivity, and anal endosonography were also performed as part of our anorectal function tests. RESULTS: No effect of age or gender was observed in either controls or patients. Patients with fecal incontinence had a higher volume at first sensation and a higher pressure at maximal toleration (P=0.03), the presence of a sphincter defect or low or normal anal pressures made no difference. Patients with constipation had a larger volume at first sensation and urge (P<0.0001 andP<0.01). Patients with a rectocele had a larger volume at first sensation (P=0.004). Patients with rectal prolapse did not differ from controls; after rectopexy, rectal compliance decreased (P<0.0003). Patients with inflammatory bowel disease had a lower rectal compliance, most pronounced in active proctitis (P=0.003). Patients with ileoanal pouches also had a lower compliance (P<0.0001). In the 17 patients where a maximal toleration volume<60 ml was found, 11 had complaints of fecal incontinence, and 6 had a stoma. In 31 patients a maximal toleration volume between 60 and 100 ml was found; 12 patients had complaints of fecal incontinence, and 6 had a stoma. Proctitis or pouchitis was the main cause for a small compliance. All 29 patients who had a maximal toleration volume>500 ml had complaints of constipation. No correlation between rectal and anal mucosal sensitivity was found. CONCLUSION: Rectal compliance measurement with a latex balloon is easily feasible. In this series of 974 patients, some patient groups showed an abnormal rectal visceral sensitivity and compliance, but there was an overlap with controls. Rectal compliance measurement gave a good clinical impression about the contribution of the rectum to the anorectal problem. Patients with proctitis and pouchitis had the smallest rectal compliance. A maximal toleration volume<60 ml always led to fecal incontinence, and stomas should be considered for such patients. A maximal toleration volume>500 ml was only seen in constipated patients, and therapy should be given to prevent further damage to the pelvic floor. Values close to or within the normal range rule out the rectum as an important factor in the anorectal problem of the patient.Drs. Sloots and Poen were supported by a grant from Janssen-Cilag. Presented at the meeting of the Dutch Society of Gastroenterology, Veldhoven, the Netherlands, October 7 to 8, 1999.  相似文献   
154.
Gersuk  GM; Carmel  R; Pattengale  PK 《Blood》1989,74(7):2330-2334
Our enzyme-linked immunosorbent assay (ELISA) for measuring human platelet-derived growth factor (PDGF) detects nanogram quantities (ranging from 0.007 to 16 ng/100 microL) in purified PDGF standards. This assay is sensitive enough for studying plasma and urine. The range in normal volunteers was 0.6 to 2.3 micrograms/L for platelet-poor plasma and 1.4 to 3.3 micrograms/L for urine. We determined PDGF levels in the circulation (outside platelets) in patients with myeloproliferative diseases. Platelet-poor plasma and urine PDGF were significantly elevated in patients with myelofibrosis (6.2 +/- 2.0 micrograms/L for plasma; 7.8 +/- 2.4 micrograms/L for urine) and essential thrombocythemia (5.5 +/- 1.5 micrograms/L for plasma; 11.4 +/- 2.2 micrograms/L for urine), but not in patients with chronic myelogenous leukemia (2.1 +/- 0.4 micrograms/L for plasma; 2.8 +/- 1.2 micrograms/L for urine). Polycythemia vera produced an intermediate pattern: although plasma PDGF was within the normal range (2.1 +/- 0.2 micrograms/L), urine levels were increased (3.7 +/- 0.6 micrograms/L). These results show that PDGF is increased in the circulation in some but not all myeloproliferative diseases, and suggest that this is due to abnormal in vivo release from either megakaryocytes in the bone marrow or circulating platelets.  相似文献   
155.
Eight-five consecutive patients with relapsed or refractory Hodgkin's disease (HD) underwent high-dose chemotherapy or chemo/radiotherapy followed by autologous bone marrow (ABMT) and/or peripheral blood stem cell (PBSC) transplantation. Two preparative regimens were used. Twenty- two patients (26%) without prior radiation received fractionated total body irradiation (FTBI) 1,200 Gy in combination with high-dose etoposide (VP-16) 60 mg/kg and cyclophosphamide (CTX) 100 mg/kg. Sixty- three patients (74%) with prior radiotherapy received carmustine (BCNU) 450 mg/m2 instead of FTBI. The median age was 32 years (range, 16 to 56). The median number of prior chemotherapy regimens was three (range, 1 to 7). Forty-three patients (51%) received transplants in first relapse or second complete remission (CR), whereas 33 (39%) received transplants after second or subsequent relapse. All relapsed patients, except one, received conventional salvage chemotherapy and/or radiotherapy in an attempt to reduce tumor bulk before transplant. At the time of analysis in April 1994, fifty-seven patients (67%) are alive, including 44 (52%) in continuous CR, with a median follow-up for the surviving patients of 28 months (range, 7 to 66). Thirty patients (35%) relapsed at a median of 9 months (range, 1 to 43). Eleven patients (13%) died of transplant-related complications including veno- occlusive disease of the liver (VOD) in five, acute and late interstitial pneumonitis in three, graft failure in one, cerebral hemorrhage in one, and therapy-induced myelodysplasia (MDS)/acute leukemia in one patient. At a median follow-up of 25 months (range, 0.6 to 66), the cumulative probability of 2-year overall and disease-free survival (DFS) of all 85 patients is 75% (95% confidence interval [CI] 64% to 84%) and 58% (95% CI 47% to 69%), respectively. Three independent prognostic variables were identified by univariate analysis: number of prior chemotherapy regimens, prior radiotherapy, and extranodal disease at ABMT. Multivariate stepwise Cox regression identified the number of prior chemotherapy regimens as the only significant prognostic factor predicting for both relapse and DFS. There were no significant differences in the outcome of the treatment between the two preparative regimens. Our results confirm that high- dose therapy and ABMT is an effective therapy for patients with relapsed or refractory HD. Earlier transplantation is recommended before the development of drug resistance and end organ damage that results from repeated attempts of salvage therapy.  相似文献   
156.
Alterations in phenotype and function of intestinal macrophages occur in inflammatory bowel disease (IBD) but it is unclear whether these changes result from the recruitment of circulating monocytes to the intestine or from proliferation of resident intestinal macrophages. We sought to demonstrate the arrival of blood monocytes, the precursors of macrophages, in IBD mucosa. Peripheral blood mononuclear cells were isolated from 23 patients with clinically active intestinal inflammation (13 Crohn's disease, eight ulcerative colitis, two infective colitis), then radiolabelled with 99mtechnetium (Tc)-stannous colloid (n=13) or 111indium (In)-oxine (n=10) before re-injection and abdominal scanning. Four patients had demonstrable intestinal monocyte uptake using [99mTc]-stannous colloid, while six [111In]-oxine-labelled monocyte scans were positive. Uptake sites correlated with actively inflamed regions. Patients demonstrating monocyte uptake had been treated with corticosteroids for a significantly (P < 0.02) shorter duration (median 3 vs 20 days) than those with negative scans. There was no significant difference between positive and negative scans for disease category, clinical or histological disease activity, or radioisotope used. Biopsies of inflamed mucosa from two patients suffering ulcerative colitis who had positive scans showed a high proportion of CD14-positive macrophages, 4–9% of which contained autoradiographic grains. These results demonstrate that blood monocytes are recruited to the mucosa of actively inflamed bowel, and suggest that this process may be inhibited by corticosteroids. Moreover, the phenotype of the recently-arrived monocytes indicates their susceptibility to stimulation by lipopolysaccharide, and suggests a mechanism for the continuing inflammation in the bacterial product-rich milieu of IBD.  相似文献   
157.
Gralnick  HR; Jackson  GM; Williams  SB; Cregger  MC 《Blood》1982,59(6):1310-1316
We have investigated the periodic acid Schiff (PAS) Coomassie staining ratio of the human factor VIII/von Willebrand factor (fVIII/vWf) protein. The PAS-Coomassie staining ratio is consistent over 8 days. The PAS-Coomassie ratio of fVIII/vWf protein purified from different starting materials does not appear to be significantly different. The PAS stain can detect as little as 300 ng of carbohydrate in the fVIII/vWf protein. Desialation did not affect the PAS-Coomassie ratio, while removal of penultimate galactose resulted in a marked reduction in the PAS-Coomassie ratio. This reduction was further accentuated with the removal of N-acetylglucosamine. The smaller multimers of the fVIII/vWf protein have a reduced sialic acid and PAS-Coomassie staining ratio. This difference does not appear to be related to the sialic acid deficiency but may be related to the distribution or organization of the carbohydrate moieties on the smaller fVIII/vWf multimers.  相似文献   
158.

Background  

Pain is still one of the most frequently occurring symptoms at the end of life, although it can be treated satisfactorily in most cases if the physician has adequate knowledge. In the Netherlands, almost 60% of the patients with non-acute illnesses die at home where end of life care is coordinated by the general practitioner (GP); about 30% die in hospitals (cared for by clinical specialists), and about 10% in nursing homes (cared for by elderly care physicians).  相似文献   
159.

Background

Chronic obstructive pulmonary disease (COPD) and asthma are underdiagnosed in primary care.

Aim

To determine how often COPD or asthma are present in middle-aged and older patients who consult their GP for persistent cough.

Design of study

A cross-sectional study in 353 patients older than 50 years, visiting their GP for persistent cough and not known to have COPD or asthma.

Setting

General practice in the Netherlands.

Method

All participants underwent extensive diagnostic work-up, including symptoms, signs, spirometry, and body plethysmography. All results were studied by an expert panel to diagnose or exclude COPD and/or asthma. The reproducibility of the panel diagnosis was assessed by calculation of Cohen''s κ statistic in a sample of 41 participants.

Results

Of the 353 participants, 102 (29%, 95% confidence interval [CI] = 24 to 34%) were diagnosed with COPD. In 14 of these 102 participants, both COPD and asthma were diagnosed (4%, 95% CI = 2 to 7%). Asthma (without COPD) was diagnosed in 23 (7%, 95% CI = 4 to 10%) participants. Mean duration of cough was 93 days (median 40 days). The reproducibility of the expert panel was good (Cohen''s κ = 0.90).

Conclusion

In patients aged over 50 years who consult their GP for persistent cough, undetected COPD or asthma is frequently present.  相似文献   
160.
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