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61.
62.
Visual neglect results from dysfunction within the spatial attention network. The structural connectivity in undamaged brain tissue in neglect has barely been investigated until now. In the present study, we explored the microstructural white matter characteristics of the contralesional hemisphere in relation to neglect severity and recovery in acute stroke patients. We compared age‐matched healthy subjects and three groups of acute stroke patients (9 ± 0.5 days after stroke): (i) patients with nonrecovered neglect (n = 12); (ii) patients with rapid recovery from initial neglect (within the first week post‐stroke, n = 7), (iii) stroke patients without neglect (n = 17). We analyzed the differences between groups in grey and white matter density and fractional anisotropy (FA) and used fiber tracking to identify the affected fibers. Patients with nonrecovered neglect differed from those with rapid recovery by FA‐reduction in the left inferior parietal lobe. Fibers passing through this region connect the left‐hemispheric analogues of the ventral attention system. Compared with healthy subjects, neglect patients with persisting neglect had FA‐reduction in the left superior parietal lobe, optic radiation, and left corpus callosum/cingulum. Fibers passing through these regions connect centers of the left dorsal attention system. FA‐reduction in the identified regions correlated with neglect severity. The study shows for the first time white matter changes within the spatial attention system remote from the lesion and correlating with the extent and persistence of neglect. The data support the concept of neglect as disintegration within the whole attention system and illustrate the dynamics of structural‐functional correlates in acute stroke. Hum Brain Mapp 35:4678–4692, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
63.

Background

Cystinuria is an inherited disorder of a renal tubular amino acid transporter and leads to increased cystine excretion with the risk of urinary stone formation. Phenotypical classification is based on urinary amino acid concentration as type I (silent), type non-I (hyper-excretors), mixed or untyped. Genotypic classification is based on mutations in SLC3A1 (type A) or SLC7A9 (type B).

Case-Diagnosis/Treatment

We present six family members with a complex phenotypic profile based on mutations in both genes. The index patient presents a known homozygous mutation (p.T189M) in SLC3A1 and a homozygous mutation (c.225C?>?T) in SLC7A9. Based on a bioinformatics analysis and published findings, we considered p.T189M to be pathogenic and initially classified c.225C?>?T as a silent variant. However, segregation analysis detected homozygosity for p.T189M also in non-affected individuals, whereas homozygous c.225C?>?T segregated with the phenotype. RNA studies confirmed c.225C?>?T to cause aberrant splicing.

Conclusions

Based on our findings, we conclude that c.225C?>?T in SLC7A9 determines the clinical phenotype in this family, whereas additional SLC3A1 mutations aggravate the phenotype in heterozygotes for c.225C?>?T in SLC7A9 without resulting in cystinuria in the homozygous state. Our results underline the need for careful biochemical characterization of family members of an index case of cystinuria. Genetic analysis of both cystinuria genes may be necessary due to the synergistic effects of mutations in two genes.  相似文献   
64.
Objective: This epidemiological study aimed to assess the proportion and extent of manifestation of enamel hypomineralization, including molar‐incisor‐hypomineralization (MIH), in the permanent and primary dentition. Methods: A total of 693 children enrolled in an ongoing birth cohort study (GINIplus‐10) were examined at their 10‐year follow‐up. Enamel hypomineralization was scored in the primary and permanent dentition on a tooth‐ and surface‐related level based on the criteria of the European Academy of Paediatric Dentistry (EAPD). Children were grouped according to their distribution pattern of enamel hypomineralization: children with a minimum of one hypomineralized tooth in the primary dentition (ht ≥ 1) and permanent dentition (HT ≥ 1); with a minimum of one hypomineralization on at least one first permanent molar (MIH); and with hypomineralization on at least one first permanent molar and permanent incisor (M + IH). For each group, the mean values of hypomineralized primary teeth (ht), permanent teeth (HT), and permanent surfaces (HS) were calculated. Results: The proportion of affected children was 36.5 percent (HT ≥ 1), 14.7 percent (MIH), and 9.4 percent (M + IH); 6.9 percent of the subjects had a minimum of one affected primary tooth (ht ≥ 1). The mean number of hypomineralized permanent teeth and surfaces were 2.3HT/2.9HS (HT ≥ 1), 3.4HT/4.8HS (MIH), and 4.2HT/5.9HS (M + IH). The mean number of hypomineralized primary teeth amounted to 0.1ht in the entire study population. Conclusions: Enamel hypomineralization can be detected frequently in this study sample. Children with M + IH showed the highest number of affected teeth and surfaces followed by those with MIH.  相似文献   
65.
66.
X-linked intellectual disability (XLID) is a genetically heterogeneous disorder with more than 100 genes known to date. Most genes are responsible for a small proportion of patients only, which has hitherto hampered the systematic screening of large patient cohorts. We performed targeted enrichment and next-generation sequencing of 107 XLID genes in a cohort of 150 male patients. Hundred patients had sporadic intellectual disability, and 50 patients had a family history suggestive of XLID. We also analysed a sporadic female patient with severe ID and epilepsy because she had strongly skewed X-inactivation. Target enrichment and high parallel sequencing allowed a diagnostic coverage of >10 reads for ~96% of all coding bases of the XLID genes at a mean coverage of 124 reads. We found 18 pathogenic variants in 13 XLID genes (AP1S2, ATRX, CUL4B, DLG3, IQSEC2, KDM5C, MED12, OPHN1, SLC9A6, SMC1A, UBE2A, UPF3B and ZDHHC9) among the 150 male patients. Thirteen pathogenic variants were present in the group of 50 familial patients (26%), and 5 pathogenic variants among the 100 sporadic patients (5%). Systematic gene dosage analysis for low coverage exons detected one pathogenic hemizygous deletion. An IQSEC2 nonsense variant was detected in the female ID patient, providing further evidence for a role of this gene in encephalopathy in females. Skewed X-inactivation was more frequently observed in mothers with pathogenic variants compared with those without known X-linked defects. The mutation rate in the cohort of sporadic patients corroborates previous estimates of 5–10% for X-chromosomal defects in male ID patients.  相似文献   
67.
Psychotic major depression (PMD) is hypothesized to be a distinct clinical entity from nonpsychotic major depression (NPMD). However, neurobiological evidence supporting this notion is scarce. The aim of this study is to identify gray matter volume (GMV) differences between PMD and NPMD and their longitudinal change following electroconvulsive therapy (ECT). Structural magnetic resonance imaging (MRI) data from 8 independent sites in the Global ECT-MRI Research Collaboration (GEMRIC) database (n = 108; 56 PMD and 52 NPMD; mean age 71.7 in PMD and 70.2 in NPMD) were analyzed. All participants underwent MRI before and after ECT. First, cross-sectional whole-brain voxel-wise GMV comparisons between PMD and NPMD were conducted at both time points. Second, in a flexible factorial model, a main effect of time and a group-by-time interaction were examined to identify longitudinal effects of ECT on GMV and longitudinal differential effects of ECT between PMD and NPMD, respectively. Compared with NPMD, PMD showed lower GMV in the prefrontal, temporal and parietal cortex before ECT; PMD showed lower GMV in the medial prefrontal cortex (MPFC) after ECT. Although there was a significant main effect of time on GMV in several brain regions in both PMD and NPMD, there was no significant group-by-time interaction. Lower GMV in the MPFC was consistently identified in PMD, suggesting this may be a trait-like neural substrate of PMD. Longitudinal effect of ECT on GMV may not explain superior ECT response in PMD, and further investigation is needed.  相似文献   
68.
Since restaurateurs can benefit by analyzing the production of meals, particularly with the dominant framework for meal experiences, the five aspects meal model (FAMM), this study examined FAMM’s relevance as an analytical tool for understanding meal production via field observations and interviews in eight small restaurants in a rural destination in Sweden. Results showed that FAMM’s aspect of the management control system and the factor of time are critical to the entire meal production process in restaurants. This article closes with a discussion of FAMM’s usefulness as a qualitative checklist for restaurateurs.  相似文献   
69.

Purpose

In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.

Methods

The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival.

Results

Donor–recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer.

Conclusions

Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms.  相似文献   
70.
Parasitology Research - Pathogenic bacteria share their natural habitat with many other organisms such as animals, plants, insects, parasites and amoeba. Interactions between these organisms...  相似文献   
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