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51.
The aim of this study was to compare three groups of Brazilian psychoactive substance (PAS) abuse patients (crack cocaine users, cocaine snorters, and non-cocaine PAS users) in terms of psychiatric comorbidities and severity of psychosocial problems. A cross-sectional, multi-center study was conducted at five Brazilian research centers. A total of 738 current PAS abusers seeking specialized treatment (outpatient and inpatient clinics) were assessed using the sixth version of the Addiction Severity Index (ASI-6): 293 patients using crack cocaine were compared with 126 using powder cocaine and 319 using non-cocaine PAS (mostly alcohol and marijuana). Psychiatric comorbidities were assessed in a smaller sample (290 cases), originating from three of the centers, using the Mini International Neuropsychiatric Interview Plus (MINI-Plus). Crack and powder cocaine users were significantly younger than non-cocaine PAS users (31.1 ± 8.1 and 32.9 ± 8.8 vs. 42.4 ± 12, respectively; p < .001). Crack users presented a higher rate of antisocial personality disorder (25%) than powder cocaine (9%) and non-cocaine PAS users (9%), even when adjusted for confounding factors (Pr = 2.6; 95% CI 1.10-6.40). According to ASI-6 summary scores, crack users presented a significantly higher rate of occupational, family, and legal problems and reported more illegal and violent activities such as burglary and theft (23%) and threatening or assaulting (32%) than non-cocaine PAS users. Our findings, combined with the recent increase observed in the prevalence of crack use in Brazil, highlight the severity of psychiatric symptoms and psychosocial problems related to this powerful drug and corroborate the already suggested association between crack/cocaine, violence, and legal problems. Treatment programs for crack users should routinely consider the possibility of associated psychiatric comorbidities, such as antisocial personality disorder, which may affect treatment outcomes.  相似文献   
52.

Background

Rituximab (RTX) has recently showed promising results in the treatment of steroid-dependent idiopathic nephrotic syndrome (SDNS).

Methods

This was a retrospective multicenter study of 18 children treated with RTX for SDNS, with a mean follow-up of 3.2 years. RTX was introduced because of side effects or relapses during therapy with immunosuppressive agents. The children received one to four infusions of RTX during the first course of treatment, and subsequent infusions were given due to CD19-cell recovery (CD19?>1 %; 54 % of children) or relapse (41 %), as well as systematically (5 %).

Results

Treatment with RTX maintained sustained remission without relapse in 22 % of patients and increased the duration of remission in all other patients. The time between two successive relapses was 9 months in the absence of re-treatment and 24.5 months when infusions were performed at the time of CD19-cell recovery. At the last follow-up, 44.5 % of patients were free of oral drug therapy. Of those still receiving oral drugs, all doses had been decreased. No serious adverse events occurred.

Conclusion

The results of this retrospective study confirm the efficacy and very good safety of RTX in the treatment of SDNS. The optimal therapeutic protocol seems to be a repeated single infusion at the time of CD19-cell recovery.  相似文献   
53.
The purpose of this study is to describe our series of nine unclippable and uncoilable ruptured aneurysms in eight patients treated by microsurgical wrapping with autologous muscle. Records were retrospectively reviewed for rebleeding rate, morbidity and mortality, changes in size or the aneurysm’s configurations, and inflammatory reaction. We conducted a Medline search in the post-microsurgical era, excluding patients in whom wrapping was part of the aneurysm treatment in combination with clipping or coiling. The surgically related morbidity was 12.5 %. Global mortality rate was 25 % due to vasospasm (one case) and rebleeding (one case). Six patients are still alive. Rebleeding rate was 14.3 % within 6 months; then, it was zero. Glasgow outcome scale (GOS) score at discharge was 1 and 4 in one patient, respectively, and 5 in the remaining six. Mean clinical follow-up was 126 months. GOS at last follow-up was 4 and 5 in 50 % of patients, respectively. Mean mRS score was 0.8 at 2 months, and 2.4 at 12 months. Follow-up MR demonstrated persistence of the aneurysm’s sac, without changes in size and configuration. Patients did not describe or exhibit symptoms attributable to complications inherent to the use of muscle. Microsurgical muscle-wrapping of ruptured intracranial aneurysm is safe, is associated with a low rate of acute and delayed postoperative complications and rebleeding, and could be a valid alternative for unclippable and non-amenable to endovascular procedure ruptured aneurysms.  相似文献   
54.
55.

Purpose

The purpose of this study was to estimate the association among the presence of subependymal nodules (SENs), subependymal giant cell tumours (SGCTs) and gene mutation in tuberous sclerosis complex (TSC) patients.

Methods

Clinical records and images of 81 TSC patients were retrospectively reviewed by two neuroradiologists in consensus. All patients were assessed for gene mutations and were categorized as TSC1 or TSC2 mutation carriers, or no-mutations-identified (NMI) patients. They underwent a brain magnetic resonance imaging (MRI) using 0.1 mmol/kg of gadobutrol. Any enhancing SEN?≥?1 cm and placed near the foramen of Monro was considered SGCT. Two MRI follow-up exams for each patient with SGCT were evaluated to assess tumour growth using Wilcoxon and chi-squared tests.

Results

Of 81 patients, 44 (54 %) were TSC2 mutation carriers, 20 (25 %) TSC1 and 17 (21 %) NMI. Nine (11 %) had a unilateral and three (4 %) a bilateral SGCT. Fifty of 81 patients (62 %) showed at least one SEN. None of the 31 patients without SEN showed SGCTs, whilst 12 (24 %) of the 50 patients with at least one SEN showed SGCTs (p?=?0.003). The association between the presence of SGCT or SEN and gene mutation was not significant (p?=?0.251 and p?=?0.187, respectively). At follow-up, the median SGCT diameter increased from 14 to 15 mm (p?=?0.017), whilst the median SGCT volume increased from 589 to 791 mm3 (p?=?0.006).

Conclusions

TSC patients with SENs are more likely to present with SGCT than those without SENs, in particular for TSC2 mutation carriers. The SGCT growth rate may be missed if based on the diameter instead of on the volume.  相似文献   
56.
In the cattle tick Rhipicephalus (Boophilus) microplus digestion of blood is intracellular, accomplished by the so-called digest cells that fill the midgut lumen. Hydrolysis of hemoglobin in the digestive vesicles of these cells results in the release of large amounts of heme, a pro-oxidant compound, whose iron atom, together with H(2)O(2), may participate in the Fenton reaction and lead to the production of hydroxyl radicals. Here, we investigated the role of catalase, an enzyme responsible for H(2)O(2) detoxification. Fully engorged female ticks injected with 3-amino-1,2,4-triazole (AT), a catalase inhibitor, showed increased H(2)O(2) in the gut, together with diminished life span and lower egg-laying rates. Increased mortality observed upon AT injection was reversed by further injection of exogenous catalase, 2 days after AT treatment, confirming that increased death was due to inhibition of this enzyme by AT. In primary cultures of digest cells, intracellular H(2)O(2) is limited to specific organelles, while treatment with AT in vitro resulted in increased H(2)O(2) spreading all over the cell, confirming the role of catalase in regulating H(2)O(2) levels. Ticks fed on a calf that had been injected with AT showed marked inhibition of catalase activity in the gut and diminished life span, oviposition and engorgement. Digest cells of these ticks had an altered morphology, showing heme spread all over the cytosol, instead of being limited to the hemosomes. The amount of aggregated heme found in isolated hemosome was also strongly decreased in AT-treated cattle. All together, our results indicate that catalase performs an important role in the control of redox balance in R. microplus, which dramatically affects hemosome formation and stability. This enzyme may be a target in the development of new methods for tick control.  相似文献   
57.
58.
This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of various doses of the anti‐CD40 monoclonal antibody bleselumab (ASKP1240) in de novo kidney transplant recipients receiving concomitant standard immunosuppression over 90 days posttransplant. Transplant recipients were randomized (1:1:1:1:1) to bleselumab 50 mg, 100 mg, 200 mg, or 500 mg, or placebo, in addition to standard maintenance immunosuppression. The primary pharmacokinetic endpoints were AUCinf, Cmax, and AUClast. The primary pharmacodynamic endpoint was B cell CD40 receptor occupancy over time. Overall, 50 kidney transplant recipients were randomized; 45 received their randomized treatment (bleselumab [n = 37] or placebo [n = 8]). AUCinf and AUClast demonstrated a more than dose‐proportional increase in the range of 50‐500 mg, and Cmax increased linearly with increasing dose. Maximal receptor occupancy for B cell CD40 was reached at all dose levels and was prolonged as dose increased. No kidney transplant recipients experienced cytokine release syndrome or a thromboembolic event. Treatment‐emergent anti‐bleselumab antibodies were found in one kidney transplant recipient in the bleselumab 50 mg group; these were detected only at Day 7. Overall, bleselumab demonstrated nonlinear pharmacokinetics and dose‐dependent prolonged B cell CD40 receptor occupancy and was well tolerated at all doses (ClinicalTrials.gov: NCT01279538).  相似文献   
59.
60.
Advances in endoscopic endonasal skull base surgery have led to the development of new routes to areas beyond the midline skull base. Recently, feasible surgical corridors to the lateral skull base have been described. The aim of this study was to describe the anatomical exposure of the ventrolateral brainstem and posterior fossa through an extended endoscopic endonasal transclival transpetrosal and transcondylar approach. Six human heads were used for the dissection process. The arterial and venous systems were injected with red- and blue-colored latex, respectively. A pre- and postoperative computed tomography (CT) scan was carried out on every head. The endoscopic endonasal transclival approach was extended through an anterior petrosectomy and a medial condylectomy. A three-dimensional model of the approach was reconstructed, using a dedicated software, from the overlapping of the pre- and post-dissection CT imaging of the specimen. An extended endoscopic transclival approach allows to gain access through an extradural anterior petrosectomy and medial condylectomy to the anterolateral surface of the brainstem and the posterior fossa. Two main intradural anatomical corridors can be described: first, between the V cranial nerve in the prepontine cistern and the VII–VIII cranial nerves in the cerebellopontine and cerebellomedullary cistern; second, between the VII–VIII cranial nerves and the IX cranial nerve, in the premedullary cistern. Extending the transclival endoscopic approach by performing an extradural anterior petrosectomy and a medial condylectomy provides a safe and wide exposure of the anterolateral brainstem with feasible surgical corridors around the main neurovascular structures.  相似文献   
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