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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   
94.

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   
95.

Purpose

In workers with musculoskeletal injuries, comorbidity is associated with worse return to work (RTW) outcomes. In the context of RTW, it is unclear whether associations between predictors and RTW are similar or different for workers with and without comorbidity. This study aims to investigate differences and similarities between workers with and without comorbidity in 12-month predictors for RTW in workers who are absent from work due to a musculoskeletal injury.

Methods

All workers with lost-time claims who were off work at baseline were selected from the Early Claimant Cohort (Canada) (n = 1,566). Follow-up data on RTW were available of 810 workers after 12 months. Predictors included demographic, health-related, and work-related factors. Differences between coefficients of the groups with and without comorbidity were tested.

Results

Low household income was a predictor for RTW in workers without comorbidity only. Better mental health was a predictor for RTW in workers with comorbidity only. Higher education, less pain intensity, better general health, less bodily pain, better physical health, and a positive supervisor response were predictors for RTW in the total group.

Conclusions

Injured workers with and without comorbidity should be considered as two distinct groups when focusing on mental health or household income.  相似文献   
96.

Background

Google Glass is a promising premarket device that includes an optical head-mounted display. Several proof of concept reports exist, but there is little scientific evidence regarding its use in a medical setting.

Objective

The objective of this study was to empirically determine the feasibility of deploying Glass in a forensics setting.

Methods

Glass was used in combination with a self-developed app that allowed for hands-free operation during autopsy and postmortem examinations of 4 decedents performed by 2 physicians. A digital single-lens reflex (DSLR) camera was used for image comparison. In addition, 6 forensic examiners (3 male, 3 female; age range 23-48 years, age mean 32.8 years, SD 9.6; mean work experience 6.2 years, SD 8.5) were asked to evaluate 159 images for image quality on a 5-point Likert scale, specifically color discrimination, brightness, sharpness, and their satisfaction with the acquired region of interest. Statistical evaluations were performed to determine how Glass compares with conventionally acquired digital images.

Results

All images received good (median 4) and very good ratings (median 5) for all 4 categories. Autopsy images taken by Glass (n=32) received significantly lower ratings than those acquired by DSLR camera (n=17) (region of interest: z=–5.154, P<.001; sharpness: z=–7.898, P<.001; color: z=–4.407, P<.001, brightness: z=–3.187, P=.001). For 110 images of postmortem examinations (Glass: n=54, DSLR camera: n=56), ratings for region of interest (z=–8.390, P<.001) and brightness (z=–540, P=.007) were significantly lower. For interrater reliability, intraclass correlation (ICC) values were good for autopsy (ICC=.723, 95% CI .667-.771, P<.001) and postmortem examination (ICC=.758, 95% CI .727-.787, P<.001). Postmortem examinations performed using Glass took 42.6 seconds longer than those done with the DSLR camera (z=–2.100, P=.04 using Wilcoxon signed rank test). The battery charge of Glass quickly decreased; an average 5.5% (SD 1.85) of its battery capacity was spent per postmortem examination (0.81% per minute or 0.79% per picture).

Conclusions

Glass was efficient for acquiring images for documentation in forensic medicine, but the image quality was inferior compared to a DSLR camera. Images taken with Glass received significantly lower ratings for all 4 categories in an autopsy setting and for region of interest and brightness in postmortem examination. The effort necessary for achieving the objectives was higher when using the device compared to the DSLR camera thus extending the postmortem examination duration. Its relative high power consumption and low battery capacity is also a disadvantage. At the current stage of development, Glass may be an adequate tool for education. For deployment in clinical care, issues such as hygiene, data protection, and privacy need to be addressed and are currently limiting chances for professional use.  相似文献   
97.
98.
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   
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100.
Clinical guidelines are used to translate research findings into evidence‐based clinical practice but are frequently not comprehensively adopted by health workers (HWs). HIV and infant feeding guidelines were revised by the World Health Organization to align feeding advice for HIV‐exposed and unexposed infants, and these were adopted in South Africa in 2017. We describe an innovative, team‐based, mentoring programme developed to update HWs on these guidelines. The intervention was underpinned by strong theoretical frameworks and aimed to improve HWs' attitudes, knowledge, confidence, and skills about breastfeeding in the context of HIV. On‐site workshops and clinical mentoring used interactive participatory methods and a simple low‐tech approach, guided by participants' self‐reported knowledge gaps. Workshops were conducted at 24 participating clinics over three sessions, each lasting 1–2 hr. Evaluation data were collected using a self‐administered questionnaire. Of 303 participating HWs, 249/303 (82.2%) attended all workshops. Achieving high workshop attendance was challenging and “catch‐up” sessions were required to achieve good coverage. Common knowledge gaps identified included antiretroviral therapy adherence monitoring during breastfeeding and management of viral load results (173 participants), management of breast conditions (79), and advice about expressing and storing breastmilk (64). Most participants reported all their knowledge gaps were addressed and anticipated that their practice would change. We describe a feasible, sustainable approach to updating HWs on HIV and infant feeding guidelines and improving skills in breastfeeding counselling in resource‐constrained settings. This approach could be adapted to other topics and, with further evaluation, implemented at scale using existing resources.  相似文献   
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