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41.
42.
We report a British family with young-onset Parkinson’s disease (PD) and a G51D SNCA mutation that segregates with the disease. Family history was consistent with autosomal dominant inheritance as both the father and sister of the proband developed levodopa-responsive parkinsonism with onset in their late thirties. Clinical features show similarity to those seen in families with SNCA triplication and to cases of A53T SNCA mutation. Post-mortem brain examination of the proband revealed atrophy affecting frontal and temporal lobes in addition to the caudate, putamen, globus pallidus and amygdala. There was severe loss of pigmentation in the substantia nigra and pallor of the locus coeruleus. Neuronal loss was most marked in frontal and temporal cortices, hippocampal CA2/3 subregions, substantia nigra, locus coeruleus and dorsal motor nucleus of the vagus. The cellular pathology included widespread and frequent neuronal α-synuclein immunoreactive inclusions of variable morphology and oligodendroglial inclusions similar to the glial cytoplasmic inclusions of multiple system atrophy (MSA). Both inclusion types were ubiquitin and p62 positive and were labelled with phosphorylation-dependent anti-α-synuclein antibodies In addition, TDP-43 immunoreactive inclusions were observed in limbic regions and in the striatum. Together the data show clinical and neuropathological similarities to both the A53T SNCA mutation and multiplication cases. The cellular neuropathological features of this case share some characteristics of both PD and MSA with additional unique striatal and neocortical pathology. Greater understanding of the disease mechanism underlying the G51D mutation could aid in understanding of α-synuclein biology and its impact on disease phenotype.  相似文献   
43.

Background

Fibromuscular dysplasia (FMD) is a non-inflammatory arteriopathy that causes significant morbidity in children.

Methods

The clinical features, presenting symptoms, and vascular beds involved are reviewed in the first 33 patients aged <18 years who are enrolled in the United States Registry for FMD from five registry sites and compared with 999 adult patients from 12 registry sites.

Results

Mean age at diagnosis was 8.4?±?4.8 years (16 days to 17 years). Compared with adults, pediatric FMD occurs in more males (42.4 vs 6 %, p?<?0.001). Children with FMD have a stronger previous history of hypertension (93.9 vs 69.9 %, p?=?0.002). Hypertension (100 %), headache (55 %), and abdominal bruits (10.7 %) were the most common presenting signs and symptoms. FMD affects renal vasculature in almost all children (97 vs 69.7 %, p?=?0.003). The extra-cranial carotid vessels are less commonly involved in children (23.1 vs 73.3 %, p?<?0.001). The mesenteric arteries (38.9 vs 16.2 %, p?=?0.02) and aorta (26.3 vs 2.4 %, p?<?0.001) are more commonly involved in children.

Conclusions

In the United States Registry for FMD, pediatric FMD affects children from infancy throughout childhood. All children presented with hypertension and many presented with headache and abdominal bruits. In children, FMD most commonly affects the renal vasculature, but also frequently involves the mesenteric arteries and abdominal aorta; the carotid vessels are less frequently involved.
  相似文献   
44.
45.

BACKGROUND:

Proximal interphalangeal joint (PIPJ) contracture is a difficult problem to treat regardless of etiology. Although numerous interventions have been recommended, published results are mediocre at best.

OBJECTIVE:

The authors describe their experience and results of using a modification of pins and rubber band traction (PRBT) – applying a dynamic extension apparatus to a contracted PIPJ using the constant traction force in a stretched rubber (elastic) band.

METHOD:

A retrospective review of patients treated with this method was performed, and the results are presented. The technique itself is described, and clinical photographs illustrate the method.

RESULTS:

Mean PIPJ flexion contracture before PRBT was 82° (range 60° to 110°). The full correction of eight contracted PIPJs in seven patients was achieved, in a mean of 17.8 days (range 14 to 31 days). At one month postremoval of PRBT, the mean PIPJ flexion contracture was 22.8° (range 0° to 46°).

DISCUSSION:

The method is compared with previously described methods of PIPJ contracture correction, whether surgical or splinting; the latter may be static, dynamic or a combination of the two. The results of previously published studies are discussed and compared with the method described.

CONCLUSION:

The present method is a powerful and effective simplification of a previously described method of correcting PIPJ contractures. This technique is simple, ‘low-tech’ and can be applied under local anesthetic; the authors believe it offers a useful adjunct to surgical release.  相似文献   
46.
Expression of a polysaccharide capsule is required for the full pathogenicity of many mucosal pathogens such as Streptococcus pneumoniae. Although capsule allows for evasion of opsonization and subsequent phagocytosis during invasive infection, its role during mucosal colonization, the organism's commensal state, remains unknown. Using a mouse model, we demonstrate that unencapsulated mutants remain capable of nasal colonization but at a reduced density and duration compared to those of their encapsulated parent strains. This deficit in colonization was not due to increased susceptibility to opsonophagocytic clearance involving complement, antibody, or the influx of Ly-6G-positive cells, including neutrophils seen during carriage. Rather, unencapsulated mutants remain agglutinated within lumenal mucus and, thus, are less likely to transit to the epithelial surface where stable colonization occurs. Studies of in vitro binding to immobilized human airway mucus confirmed the inhibitory effect of encapsulation. Likewise, pneumococcal variants expressing larger amounts of negatively charged capsule per cell were less likely to adhere to surfaces coated with human mucus and more likely to evade initial clearance in vivo. Removal of negatively charged sialic acid residues by pretreatment of mucus with neuraminidase diminished the antiadhesive effect of encapsulation. This suggests that the inhibitory effect of encapsulation on mucus binding may be mediated by electrostatic repulsion and offers an explanation for the predominance of anionic polysaccharides among the diverse array of unique capsule types. In conclusion, our findings demonstrate that capsule confers an advantage to mucosal pathogens distinct from its role in inhibition of opsonophagocytosis--escape from entrapment in lumenal mucus.  相似文献   
47.
It is generally accepted that cerebrospinal fluid (CSF) biomarkers such as tau protein, phosphorylated tau protein (threonine 181) and beta-amyloid (1-42) can facilitate early and differential diagnosis of Alzheimer's disease (AD). Since the respective concentrations can only be measured in a number of specialized centers, time to CSF specimen work-up has been considered as crucial for the stability of the respective biomarkers. When shipping of CSF samples is needed for biomarker measurement and immediate freezing of samples is not available, an overnight delay of up to 24h frequently occurs. Therefore, we investigated the potential impact of a 24h delayed freezing on CSF biomarker concentrations and compared it to 2h storage (room temperature, 20 degrees C) and an immediate freezing. First, storage at room temperature for 2h had only marginal, non-significant effects on the concentrations of CSF total tau protein and phospho-tau protein (181) compared to immediate freezing. Second, storage at room temperature for 24h did not significantly affect total tau protein or phospho-tau protein but beta-amyloid (1-42) concentrations which increased significantly compared to the samples frozen immediately. These results indicate that CSF samples for the evaluation of total tau and phospho-tau protein may be kept at room temperature for up to 24h whereas CSF samples for beta-amyloid (1-42) need to be frozen immediately.  相似文献   
48.
To investigate the interface between primary care and paediatric services in the referral of asylum seekers. Over a 3 month period a questionnaire was administered, and clinical data gathered on every child attending the A&E department of UCHG whose parents were seeking asylum in this country. Control data was obtained for the next Irish child seen on-call. At the time of presentation to the paediatric service, an Irish child was 4 times more likely (32%) to have initially been seen and referred by a GP than an asylum seeker child (8%); 80% of asylum seeker families had registered with a GP, compared to 96% of controls. 24% of asylum seeker families had called and used an emergency response ambulance to get to hospital, compared to just 4% of Irish children. The rate of subsequent admission to the paediatric ward from A&E was nearly that in asylum seeker children (24%) compared to Irish controls (40%), get to hospital, compared to just 4% of Irish children. Asylum seeker children are less likely to have seen a GP prior to A&E presentation, more likely to go to hospital by ambulance and less likely to be subsequently admitted, suggesting an over-dependence on paediatric hospital services in this population.  相似文献   
49.
50.

Objectives

Caution is advised when prescribing antipsychotics to people with dementia. This study explored the determinants of appropriate, evidence-based antipsychotic prescribing behaviors for nursing home residents with dementia, with a view to informing future quality improvement efforts and behavior change interventions.

Design

Semistructured qualitative interviews based on the Theoretical Domains Framework (TDF).

Setting and Participants

A purposive sample of 27 participants from 4 nursing homes, involved in the care of nursing home residents with dementia (8 nurses, 5 general practitioners, 5 healthcare assistants, 3 family members, 2 pharmacists, 2 consultant geriatricians, and 2 consultant psychiatrists of old age) in a Southern region of Ireland.

Measures

Using framework analysis, the predominant TDF domains and determinants influencing these behaviors were identified, and explanatory themes developed.

Results

Nine predominant TDF domains were identified as influencing appropriate antipsychotic prescribing behaviors. Participants’ effort to achieve “a fine balance” between the risks and benefits of antipsychotics was identified as the cross-cutting theme that underpinned many of the behavioral determinants. On one hand, neither healthcare workers nor family members wanted to see residents over-sedated and without a quality of life. Conversely, the reality of needing to protect staff, family members, and residents from potentially dangerous behavioral symptoms, in a resource-poor environment, was emphasized. The implementation of best-practice guidelines was illustrated through 3 explanatory themes (“human suffering”; “the interface between resident and nursing home”; and “power and knowledge: complex stakeholder dynamics”), which conceptualize how different nursing homes strike this “fine balance.”

Conclusions

Implementing evidence-based antipsychotic prescribing practices for nursing home residents with dementia remains a significant challenge. Greater policy and institutional support is required to help stakeholders strike that “fine balance” and ultimately make better prescribing decisions. This study has generated a deeper understanding of this complex issue and will inform the development of an evidence-based intervention.  相似文献   
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