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61.
Upper extremity digital ischaemia (UEDI) is a rare heterogeneous condition whose frequency is 40 times less than that of toe ischaemia. Using a large cohort, the aim of this study was to evaluate aetiologies, prognosis and midterm clinical outcomes of UEDI.All patients with UEDI with or without cutaneous necrosis in a university hospital setting between January 2000 to December 2016 were included. Aetiologies, recurrence of UEDI, digital amputation and survival were analyzed retrospectively.Three hundred twenty three patients were included. UEDI due to cardio-embolic disease (DICE) was the highest occurring aetiology with 59 patients (18.3%), followed by DI due to Systemic Sclerosis (SSc) (16.1%), idiopathic causes (11.7%), Thromboangiitis obliterans (TAO) (9.3%), iatrogenic causes (9.3%), and cancer (6.2%). DICE patients tended to be older and featured more cases with arterial hypertension whereas TAO patients smoked more tobacco and cannabis. During follow-up, recurrences were significantly more frequent in SSc than in all other tested groups (P < .0001 vs idiopathic and DICE, P = .003 vs TAO) and among TAO patients when compared to DICE patients (P = .005). The cumulated rate of digital amputation was higher in the SSc group (n = 18) (P = .02) and the TAO group (n = 7) (P = .03) than in DICE (n = 2).This retrospective study suggests that main aetiologies of UEDI are DICE, SSc and idiopathic. This study highlights higher frequency of iatrogenic UEDI than previous studies. UEDI associated with SSc has a poor local prognosis (amputations and recurrences) and DICE a poor survival. UEDI with SSc and TAO are frequently recurrent.  相似文献   
62.
Voltage-gated calcium channels have an important role in neurotransmission. Aberrations affecting genes encoding the alpha subunit of these channels have been associated with epilepsy and neuropsychiatric disorders such as autism or schizophrenia. Here we report three patients with a genomic aberration affecting the CACNA2D1 gene encoding the α2δ subunit of these voltage-gated calcium channels. All three patients present with epilepsy and intellectual disability pinpointing the CACNA2D1 gene as an interesting candidate gene for these clinical features. Besides these characteristics, patient 2 also presents with obesity with hyperinsulinism, which is very likely to be caused by deletion of the CD36 gene.  相似文献   
63.
Gay  JC; Beckman  JK; Brash  AR; Oates  JA; Lukens  JN 《Blood》1984,64(4):780-785
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci.  相似文献   
64.
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites.  相似文献   
65.
Glanzmann's thrombasthenia is a bleeding disorder, inherited in an autosomal recessive way and characterized by an absence or deficiency of the platelet glycoprotein (GP) IIb/IIIa complex. Recently, we and others demonstrated that cultured human umbilical vein endothelial cells synthesized a membrane protein complex similar to the platelet GP IIb/IIIa complex. In this article, we demonstrate that endothelial cells isolated from the umbilical vein of a newborn with Glanzmann's thrombasthenia, as compared with normal endothelial cells, show no difference in their ability to synthesize and express this GP IIb/IIIa complex. Our results indicate that Glanzmann's thrombasthenia is not accompanied by an "endotheliopathy."  相似文献   
66.

Background

Lumbar-flexion-based endurance training, namely cycling, could be effective in reducing pain and improving function and health-related quality of life in older people with chronic low back pain.

Objectives

To assess barriers and facilitators to home-based cycling in older patients with lumbar spinal stenosis (LSS).

Methods

We conducted a retrospective mixed-method study. Patients  50 years old followed up for LSS from November 2015 to June 2016 in a French tertiary care center were screened. The intervention consisted of a single supervised session followed by home-based sessions of cycling, with dose (number of sessions and duration, distance and power per session) self-determined by patient preference. The primary outcome was assessed by a qualitative approach using semi-structured interviews at baseline and 3 months and was the identification of barriers and facilitators to the intervention. Secondary outcomes were assessed by a quantitative approach and were adherence monitored by a USB stick connected to the bicycle, burden of treatment assessed by the Exercise Therapy Burden Questionnaire (ETBQ) and clinical efficacy assessed by change in lumbar pain, radicular pain, disability, spine-specific activity limitation and maximum walking distance at 3 months.

Results

Overall, 15 patients were included and data for 12 were analyzed at 3 months. At baseline, the mean age was 70.9 years (95% CI: 64.9–76.8) and 9/15 patients (60.0%) were women. Barriers to cycling were fear of pain and fatigue, a too large bicycle, burden of hospital follow-up and lack of time and motivation. Facilitators were clinical improvement, surveillance and ease-of-use of the bicycle. Adherence remained stable overtime. The burden of treatment was low [mean ETBQ score: 21.0 (95% confidence interval: 11.5–30.5)]. At 3 months, 7/12 patients (58.3%) self-reported clinical improvement, with reduced radicular pain and disability [mean absolute differences: ?27.5 (?43.3 to ?11.7), P < 0.01 and ?17.5 (?32.1 to ?2.9), P = 0.01, respectively].

Conclusions

For people with LSS, home-based cycling is a feasible intervention.  相似文献   
67.
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
68.
Sixty-three patients with high tumor mass multiple myeloma were treated with high-dose chemotherapy and total body irradiation supported by autologous blood stem cell transplantation. After high-dose therapy, they were monitored for a median of 44 months. Seven patients died early from toxicity. All the other patients, including those whose disease was resistant to previous therapies, showed a tumor mass reduction. At 6 months postengraftment, 40 (71%) of the surviving patients had minimal residual disease and 11 (20%) were in apparent complete remission. During follow-up, 25 out of the 63 (39%) patients relapsed and 16 of these died; 31 (49%) had a sustained remission. The median overall and event-free survival times after transplantation were 59 and 43 months, respectively. The initial serum beta 2-microglobulin value (> or < 2.8 mg/L) and length of previous therapy (> or < 6 courses of chemotherapy) were the only significant prognostic factors. In all surviving patients, blood stem cell autograft provided satisfactory and sustained haematopoietic reconstitution most often within 15 days. High dose chemoradiotherapy followed by autologous blood stem cell transplantation is thus an important therapeutic option for young patients with aggressive multiple myeloma.  相似文献   
69.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease that predominantly affects the right ventricle and is associated with ventricular arrhythmias that may lead to sudden cardiac death. Mutations within at least seven separate genes have been identified to cause ARVC, however a genetic culprit remains elusive in approximately 50% of cases. Although negative genetic testing may be secondary to pathogenic mutations within undiscovered genes, an alternative explanation may be the presence of large deletions or duplications involving known genes. These large copy number variants may not be detected with standard clinical genetic testing which is presently limited to direct DNA sequencing. We describe two cases of ARVC possessing large deletions involving plakophilin‐2 (PKP2) identified with microarray analysis and/or multiplex ligation‐dependent probe amplification (MLPA) that would have been classified as genotype negative with standard clinical genetic testing. A deletion of the entire coding region of PKP2 excluding exon 1 was identified in patient 1 and his son. In patient 2, MLPA analysis of PKP2 revealed deletion of the entire gene with subsequent microarray analysis demonstrating a de novo 7.9 Mb deletion of chromosome 12p12.1p11.1. These findings support screening for large copy number variants in clinically suspected ARVC cases without clear disease causing mutations following initial sequencing analysis.  相似文献   
70.
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