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51.
Chronic pain is gender-related, since there is a clear predominance of one sex with respect to the other in most pain syndromes. Gonadal hormones are known to affect the occurrence and incidence of pain. Transsexuals receive cross-sex hormones to develop and maintain somatic characteristics of the opposite sex: male to female transsexuals (MtF) are administered estrogens and anti-androgens, while female to male transsexuals (FtM) are administered androgens. Hence, these subjects represent a model to study the relationship between sex hormones and pain. Questionnaires dealing with sociodemographic data and pain (occurrence, frequency, duration, intensity, location and associated symptoms) were administered to both MtF and FtM transsexuals under hormone treatment for sex reassignment for at least 1 year. Forty-seven MtF and 26 FtM completed the questionnaires. Fourteen of the 47 MtF (29.8%) reported painful conditions, which in 11 subjects were not present before the beginning of hormone treatment. Pain consisted mainly of headaches and breast and musculoskeletal pain. Five subjects suffered from more than one pain condition. Sixteen of the 26 FtM (61.5%) reported pain. In 11 subjects, the pain was present before the beginning of hormone intake, and in 6 of them it improved after testosterone administration. These data suggest that marked changes in sex hormones affect the occurrence of pain in a high percentage of humans but not in all of them. Whether these effects are due to peripheral or central actions of sex steroids is unknown.  相似文献   
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The outcome of steroid-dependent or frequently relapsing nephrotic syndrome of minimal change disease (MCD), mesangial proliferative GN (MesGN), or FSGS may be poor and with major treatment toxicity. This academic, multicenter, off-on trial (ClinicalTrials.gov #NCT00981838) primarily evaluated the effects of rituximab therapy followed by immunosuppression withdrawal on disease recurrence in 10 children and 20 adults with MCD/MesGN (n=22) or FSGS who had suffered ≥2 recurrences over the previous year and were in steroid-induced remission for ≥1 month. Participants received one dose (n=28) or two doses of rituximab (375 mg/m2 intravenously). At 1 year, all patients were in remission: 18 were treatment-free and 15 never relapsed. Compared with the year before rituximab treatment, total relapses decreased from 88 to 22 and the per-patient median number of relapses decreased from 2.5 (interquartile range [IQR], 2–4) to 0.5 (IQR, 0–1; P<0.001) during 1 year of follow-up. Reduction was significant across subgroups (children, adults, MCD/MesGN, and FSGS; P<0.01). After rituximab, the per-patient steroid maintenance median dose decreased from 0.27 mg/kg (IQR, 0.19–0.60) to 0 mg/kg (IQR, 0–0.23) (P<0.001), and the median cumulative dose to achieve relapse remission decreased from 19.5 mg/kg (IQR, 13.0–29.2) to 0.5 mg/kg (IQR, 0–9.4) (P<0.001). Furthermore, the mean estimated GFR increased from 111.3±25.7 to 121.8±29.2 ml/min per 1.73 m2 (P=0.01), with the largest increases in children and in FSGS subgroups. The mean height z score slope stabilized in children (P<0.01). Treatment was well tolerated. Rituximab effectively and safely prevented recurrences and reduced the need for immunosuppression in steroid-dependent or frequently relapsing nephrotic syndrome, and halted disease-associated growth deficit in children.Idiopathic nephrotic syndrome (NS) in children and young adults is almost invariably the clinical counterpart of a continuum of glomerular diseases ranging from the relatively frequent minimal change disease (MCD) and the less frequent mesangial proliferative GN (MesGN), which are predominantly observed in children, to the relatively uncommon FSGS that is observed more frequently in adult patients.1 In a small minority of patients that are generally resistant to immunosuppressive therapies, the disease is due to molecular defects of one of the podocyte genes.2 In all of the other cases, it appears to be immune-mediated, but the pathophysiologic process underlying glomerular injury remains poorly understood.3Independent of the underlying renal pathology, prednisone continues to be the cornerstone treatment at disease onset, achieving remission within 4 weeks in approximately 90% of children with MCD and in 20%–60% of those with FSGS.4,5 However, 60%–70% of patients relapse after steroid tapering or withdrawal, and most require repeat courses of prednisone to achieve remission of recurrent episodes and/or the addition of other immunosuppressive medications, such as calcineurin inhibitors, mycophenolate mofetil, or alkylating agents, to reduce the number of relapses and prevent major side effects of steroid treatment.6 According to their relapse rate, these patients are classically labeled as “steroid-dependent” or “frequently relapsing”. In these patients, serious adverse effects of treatment associate with complications of relapsing episodes of heavy proteinuria. These are the patients in most urgent need of more effective and safer treatment.The possibility of a specific and, hopefully, safer approach to patients with steroid-dependent or frequently relapsing NS emerged in 2004 when the B cell–depleting mAb rituximab was reported to induce remission of proteinuria in a child with frequently relapsing NS secondary to MCD who had received this medication to cure a supervened idiopathic thrombocytopenic purpura.7 Subsequent uncontrolled observations found some effect of rituximab in patients with steroid-dependent or frequently relapsing MCD,811 suggesting that B-cell immunity could play a key role in the pathophysiology of the disease. Controlled studies in support of this hypothesis, however, have been both scanty and almost confined to children12,13 or to patients with MCD who were evaluated in the context of a retrospective, observational design.14 Indeed, less attention was given to adults and patients with FSGS given difficulties in designing adequately powered trials.Here, we designed a longitudinal, off-on study (ClinicalTrials.gov #NCT00981838) to evaluate the efficacy of rituximab in reducing the incidence of relapses and need for steroid and other immunosuppressive medications in children and adults with steroid-dependent or frequently relapsing NS due to MCD, MesGN, or FSGS. To minimize the side effects and costs of rituximab, we abandoned the standard four-dose protocol originally implemented for the treatment of B-cell lymphomas,15 and adopted a new B cell–driven regimen we found to achieve remission of NS in patients with idiopathic membranous nephropathy (IMN) as effectively as the standard protocol, but with fewer side effects and less costs.16  相似文献   
54.
We investigated whether changes in iron metabolism and the transferrin receptor (TRF-R) expression were involved in the antileukaemic effects of arabinoside cytosine (ara-C). Treatment with 100 n M ara-C for 48 h reduced thymidine uptake and increased the surface expression of the TRF-R on leukaemic blasts derived from 13/16 (81%) patients and on the HL-60 and U-937 cell lines. Whereas intracellular non-haem iron was strongly depleted 24 h after ara-C addition, TRF-R up-regulation and recovery of intracellular non-haem iron concentration occurred together after a longer exposure of the cultured cells to the drug. Since iron is an essential regulator of cell proliferation we have evaluated the effects of the combination between ara-C and the iron chelator desferioxamine (DSF) on the growth of HL-60 and U-937 cells. We found that desferioxamine strongly potentiated the effects of ara-C on leukaemic cell growth inhibition and apoptosis. This is the first report of a positive interaction between ara-C and an iron chelator in terms of antileukaemic effects.  相似文献   
55.

Background

Self-expandable metallic stents can be used to treat patients with symptomatic anastomotic complications after colorectal resection.

Methods

Twenty patients with symptomatic anastomotic stricture after colorectal resection were treated with endoscopic placement of a self-expandable metal stent. Ten patients had “simple” anastomotic stricture. In the remaining 10 patients, a leak was associated with the stricture.

Results

The anastomotic leakage healed without evidence of residual stricture or major fecal incontinence in 8 of 10 patients. Overall, the anastomotic stricture was resolved in 14 of the 20 patients.

Conclusions

Self-expandable metal stents represent a valid adjunctive to treat patients with symptomatic anastomotic complications after colorectal resection for cancer. They have a complementary role to balloon dilatation in case of simple anastomotic stricture, and they improve the rate of healing when the stricture is associated with a leak.  相似文献   
56.
57.
Myelodysplastic syndromes (MDS) are common in elderly patients. Recombinant human erythro-poietin (rHuEPO) has been widely used to treat anemia in lower risk MDS patients, but few data are known about rHuEPO treatment in the very elderly patient group. In order to investigate the role of rHuEPO treatment in terms of response, overall survival (OS), and toxicity in a very elderly MDS patient group, 93 MDS patients treated with rHuEPO when aged ≥80 years were selected among MDS cases enrolled in a retrospective multicenter study by the cooperative group Gruppo Romano Mielodisplasie (GROM) from Jan 2002 to Dec 2010. At baseline, median age was 82.7 (range 80–99.1) with a median hemoglobin (Hb) level of 9 g/dl (range 6–10.8). The initial dose of rHuEPO was standard (epoetin alpha 40,000 IU/week or epoetin beta 30,000 IU/week) in 59 (63.4 %) pa-tients or high in 34 (36.6 %) (epoetin alpha 80,000 IU/week) patients. We observed an erythroid response (ER) in 59 (63.4 %) patients. No thrombotic event was reported. Independent predictive factors for ER were low transfusion requirement before treatment (p?=?0.004), ferritin <200 ng/ml (p?=?0.017), Hb >8 g/dl (p?=?0.034), and a high-dose rHuEPO treatment (p?=?0.032). Median OS from rHuEPO start was 49.3 months (95 % CI 27.5–68.4) in responders versus 30.6 months (95 % CI 7.3–53.8) in resistant patients (p?=?0.185). In conclusion, rHuEPO treatment is safe and effective also in the very elderly MDS patients. However, further larger studies are warranted to evaluate if EPO treatment could be worthwhile in terms of quality of life and cost-efficacy in very old patients.  相似文献   
58.
Adult patients with Niemann-Pick disease type C (NPC) usually develop cognitive impairment progressing to dementia, whose pathophysiology remains still unclear. Noteworthy parallels exist in cognitive impairment and cellular pathology of NPC and Alzheimer’s disease (AD). In particular, alterations of cholinergic system, which represent one of the pathological hallmarks and contribute to cognitive deterioration in AD, have recently been demonstrated in a human brain autopsy and in an experimental model of NPC. This finding raised the issue that central cholinergic circuits dysfunction may contribute to pathophysiology of cognitive impairment in NPC as well, and prompted us to evaluate the cholinergic functional involvement in NPC patients by applying a neurophysiologic technique, named short-latency afferent inhibition (SAI). We describe clinical, biochemical, molecular and neuropsychological features, and SAI findings in three patients affected by NPC. Diagnosis of NPC was assessed by molecular analysis of the NPC1 gene in all patients. In two of them, biochemical analysis of intracellular accumulation of unesterified cholesterol was also performed. The main clinical features were cerebellar ataxia, vertical supranuclear gaze palsy and a variable degree of cognitive impairment ranging from only memory impairment to severe dementia. Electrophysiological evaluation revealed a reduced SAI in all three patients. Our SAI findings provide evidence of cholinergic dysfunction in patients with the adult form of NPC, supporting that cholinergic alterations may play a role in cognitive impairment in NPC, and strengthening the similarities between NPC and AD.  相似文献   
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60.
A copper-based metal–organic framework (MOF) was prepared using a new linker, a 5-substituted isophthalic acid bearing a propargyl carbamate group, intended to provide a terminal alkyne function protruding from the material surface to generate supported gold species for potential catalytic applications. The novel material was fully characterized by spectroscopic analyses of different kinds: FTIR, Raman, EDX, and XPS, as well as by thermal and surface area measurements. Synchrotron X-ray diffraction data analysis, in particular, revealed that this MOF, labelled [Cu(1,3-YBDC)]·xH2O (x ∼ 2), where Y stands for the pendant alkYne and BDC for benzene dicarboxylate, contains a complex network of 5-substituted isophthalate anions bound to Cu(ii) centers, arranged in pairs within paddlewheel (or “Chinese lantern”) fragments of Cu2(μ-COO)4(D)2 formulation (D being a neutral Lewis base), with a short Cu⋯Cu distance of 2.633(4) Å. Quite unexpectedly, the apical atom in the paddlewheel structure belongs to the carbamate carbonyl oxygen atom. Such extra coordination by the propargyl carbamate groups drastically reduces the MOF porosity, a feature that was also confirmed by BET measurements. However, the MOF functionality is retained at the external crystal surface where 2% of active terminal alkynes is located.

A copper-based metal–organic framework with a novel 5-substituted isophthalic linker bearing a propargyl carbamate group protruding from the material surface.  相似文献   
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