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Background

Down’s syndrome (DS) is the most common genetic cause of intellectual disability. People with DS are at an increased risk of Alzheimer’s disease (AD) compared to the general population. Neuroimaging studies of AD have focused on medial temporal structures; however, to our knowledge, no in vivo case–control study exists comparing the anatomy of dementia in DS to people with AD in the general population. We therefore compared the in vivo brain anatomy of people with DS and dementia (DS+) to those with AD in the general population.

Method

Using MRI in 192 adults, we compared the volume of whole brain matter, lateral ventricles, temporal lobes and hippocampus in DS subjects with and without dementia (DS+, DS-), to each other and to three non-DS groups. These included one group of individuals with AD and two groups of controls (each age-matched for their respective DS and general population AD cohorts).

Results

AD and DS+ subjects showed significant reductions in the volume of the whole brain, hippocampus and temporal lobes and a significant elevation in the volume of the lateral ventricle, compared to their non-demented counterparts. People with DS+ had a smaller reduction in temporal lobe volume compared to individuals with AD.

Conclusions

DS+ and AD subjects have a significant reduction in volume of the same brain regions. We found preliminary evidence that DS individuals may be more sensitive to tissue loss than others and have less ‘cognitive reserve’.  相似文献   
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IB1001 trenacog alfa is an investigational recombinant factor IX (FIX) for the treatment and prevention of bleeding in individuals with haemophilia B. To compare the pharmacokinetics (PK) of IB1001 with nonacog alfa in individuals with haemophilia B and to assess the relationship between sialylation and PK of IB1001 (NCT00768287). A randomized, double‐blind, non‐inferiority, cross‐over study conducted in participants aged ≥12 years weighing ≥40 kg, with severe or moderately severe haemophilia B (FIX activity ≤2 IU dL ?1). PK parameters were derived using observed FIX concentration levels and actual PK sampling times, and repeated in a subset of participants who had received IB1001 prophylaxis for 4–18 months. A retrospective analysis was conducted in subgroups according to the sialylation levels of IB1001 (50.8, 57.8–59.0%, or 71.7%). In the 32 adolescent and adult males evaluated, there were no clinically meaningful differences in PK parameters between those receiving IB1001 75 IU kg?1 or nonacog alfa. The lower limit of the one‐sided 95% confidence interval for the ratio of AUC0‐t and AUC0‐∞ (IB1001/nonacog alfa) was 0.90, establishing non‐inferiority. Terminal phase half‐lives were similar (29.7 ± 18.2 h for IB1001 and 33.4 ± 21.2 h for nonacog alfa). The PK results were stable for up to 18 months of IB1001 exposure; the impact of sialylation levels was not clinically meaningful. There were no clinically meaningful PK differences between IB1001 and nonacog alfa. IB1001 was well tolerated and without safety concerns. The non‐inferiority of IB1001 to nonacog alfa supports IB1001 becoming a useful alternative recombinant agent for the management of haemophilia B.  相似文献   
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Montano  V.  Orsucci  D.  Carelli  V.  La Morgia  C.  Valentino  M. L.  Lamperti  C.  Marchet  S.  Musumeci  O.  Toscano  A.  Primiano  G.  Santorelli  F. M.  Ticci  C.  Filosto  M.  Rubegni  A.  Mongini  T.  Tonin  P.  Servidei  S.  Ceravolo  R.  Siciliano  G.  Mancuso  Michelangelo 《Journal of neurology》2022,269(3):1413-1421
Journal of Neurology - Both prevalence and clinical features of the various movement disorders in adults with primary mitochondrial diseases are unknown. Based on the database of the...  相似文献   
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Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..  相似文献   
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This multi-center Italian prospective observational study reports the 4 months follow-up data of 87 patients affected by chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN) shifted from intravenous to subcutaneous immunoglobulin treatment. A therapeutic shift from intravenous to subcutaneous immunoglobulin was performed in 87 patients (66 CIDP; 21 MMN) affected by immune-mediated peripheral neuropathies with evidence of a sustained clinical response to intravenous immunoglobulin. Patients were evaluated by means of the Overall Neuropathy Limitation Scale, Medical Research Council Scale and Life Quality Index questionnaire, both at the time of therapeutic shift and after 4 months of subcutaneous immunoglobulin treatment. A sustained clinical efficacy was observed after the switch to subcutaneous immunoglobulin: the Overall Neuropathy Limitation Scale score improved in the group of 66 CIDP patients (P = 0.018), with only one subject reporting a worsening of 1 point, and remained stable in the group of 21 MMN patients (P = 0.841), with one subject reporting a worsening of two points. An improvement in the patient’s perception of therapeutic setting was reported in both groups. This large multi-center study confirms the short-term clinical equivalence of subcutaneous versus intravenous immunoglobulin and a possible improvement in the patient’s perception of therapeutic setting with the subcutaneous administration. However, further studies are required to extend the results to a longer observational period.  相似文献   
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