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11.
Pathogenic variants in the gene HGSNAT (heparan‐α‐glucosaminide N‐acetyltransferase) have been reported to underlie two distinct recessive conditions, depending on the specific genotype, mucopolysaccharidosis type IIIC (MPSIIIC)—a severe childhood‐onset lysosomal storage disorder, and adult‐onset nonsyndromic retinitis pigmentosa (RP). Here we describe the largest cohort to‐date of HGSNAT‐associated nonsyndromic RP patients, and describe their retinal phenotype, leukocyte enzymatic activity, and likely pathogenic genotypes. We identified biallelic HGSNAT variants in 17 individuals (15 families) as the likely cause of their RP. None showed any other symptoms of MPSIIIC. All had a mild but significant reduction of HGSNAT enzyme activity in leukocytes. The retinal condition was generally of late‐onset, showing progressive degeneration of a concentric area of paramacular retina, with preservation but reduced electroretinogram responses. Symptoms, electrophysiology, and imaging suggest the rod photoreceptor to be the cell initially compromised. HGSNAT enzymatic testing was useful in resolving diagnostic dilemmas in compatible patients. We identified seven novel sequence variants [p.(Arg239Cys); p.(Ser296Leu); p.(Phe428Cys); p.(Gly248Ala); p.(Gly418Arg), c.1543‐2A>C; c.1708delA], three of which were considered to be retina‐disease‐specific alleles. The most prevalent retina‐disease‐specific allele p.(Ala615Thr) was observed heterozygously or homozygously in 8 and 5 individuals respectively (7 and 4 families). Two siblings in one family, while identical for the HGSNAT locus, but discordant for retinal disease, suggest the influence of trans‐acting genetic or environmental modifying factors.  相似文献   
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Quality of Life Research - We investigated how quality of life (QoL) changed between 2018 and 2020, and how its related factors, i.e., communication with friends and family, loneliness, and...  相似文献   
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Our aim was to study the associations between maternal vitamin C and iron intake during pregnancy and the offspring’s risk of developing islet autoimmunity and type 1 diabetes. The study was a part of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) prospective birth cohort including children genetically at risk of type 1 diabetes born between 1997–2004. The diets of 4879 mothers in late pregnancy were assessed with a validated food frequency questionnaire. The outcomes were islet autoimmunity and type 1 diabetes. Cox proportional hazards regression analysis adjusted for energy, family history of diabetes, human leukocyte antigen (HLA) genotype and sex was used for statistical analyses. Total intake of vitamin C or iron from food and supplements was not associated with the risk of islet autoimmunity (vitamin C: HR 0.91: 95% CI (0.80, 1.03), iron: 0.98 (0.87, 1.10)) or type 1 diabetes (vitamin C: 1.01 (0.87, 1.17), iron: 0.92 (0.78, 1.08)), neither was the use of vitamin C or iron supplements associated with the outcomes. In conclusion, no association was found between maternal vitamin C or iron intake during pregnancy and the risk of islet autoimmunity or type 1 diabetes in the offspring.  相似文献   
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Neurosurgical Review - “Benign” metastatic leiomyomas (BML) are indolently growing metastatic tumors which mostly associate with uterine leiomyomas in women in reproductive ages. The...  相似文献   
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Neuromagnetic responses were recorded with a 24 SQUID magnetometer in two oddball experiments to determine whether mismatch responses to changes in single stimulus features are additive. In experiment 1, the one feature deviants differed from standards in interstimulus interval (ISI) or frequency, and the two feature deviants in both ISI and frequence. In experiment 2, deviants differed in duration, frequency, or both. All deviants evoked a mismatch field (MMF) with sources close to each other in the supratemporal auditory cortex. Except for the ISI deviants, the MMF sources were about 1 cm anterior to the source of the 100ms response, N100m, to the standards. In the two experiments, MMFs obtained in response to the two feature deviants resembled closely the sum of MMFs in response to one feature deviants. The results suggest that the standards leave a multiple neuronal representation in the human auditory cortex. The particular neuronal traces of the representation react independently to changes in different features of sound stimuli.  相似文献   
17.
Serotonin transporter (5-HTT), a transmembrane protein, has been shown in adult brain to be distributed not only on synaptic terminals but to a great extent on axons as well. Here we report the ontogeny of 5-HTT and its relationship with serotonin (5-HT) neurons using established 5-HTT and 5-HT antibodies. Both 5-HTT- and 5-HT-immunostaining (-im) appear in 5-HT neurons at embryonic day 12 (E12) in rostral raphe nuclei (RRN). Soon after appearing, 5-HTT-im is highly expressed on axons, similar to adult expression. However, in contrast to adult, 5-HTT-im also outlines the soma-dendrites. Rich 5-HTT-im appears along the entire length of projecting axons, extending to the growth tip. In the next 2 days, intensive 5-HTT-im axons from RRN travel a course preferentially in the floor plate and later, the medial forebrain bundle trajectory. A group of new 5-HT-im neurons and 5-HTT-im axons appear at E13 in caudal raphe nuclei. At E16-18, taking the exact trajectory course of 5-HT axons, 5-HTT-im axons reach ganglionic eminence, olfactory bulb, and cortex and disperse into many brain regions in E18-20. No 5-HTT-im cell bodies were seen in nigral, locus ceruleus, or hypothalamus. However, the transient expression of 5-HTT on non-serotonergic system was seen in cortical and striatal neuroepithelia at E12 and sensory thalamic pathways at P0-P10. Prominent 5-HTT-im fibers in thalamocortical bundles project from sensory thalamic nuclei through reticular nucleus, internal capsule bundle and form barrels in somatosensory cortices. No 5-HTT-im was seen in glia-like cells using currently available antibody. These observations indicate that 5-HTT is: (a) associated preferentially with 5-HT neurons in brainstem, (b) temporally co-expressed with 5-HT in 5-HT neurons, (c) expressed on axons prior to synaptical sites at target neurons, which strongly indicates a volumic (extrasynaptic) transmission, (d) expressed in non-5-HT neurons within a specific window, which may affect the development of the systems "borrowing" the 5-HT. The early appearance of 5-HTT may also endow functionality as well as vulnerabilities of 5-HT, sensory thalamic, and cortical neurons to 5-HTT targeting drugs during pregnancy and after birth.  相似文献   
18.
Ultrasonically activated shears in thyroidectomies: a randomized trial   总被引:13,自引:0,他引:13       下载免费PDF全文
OBJECTIVE: To test whether the advantages of the ultrasonically activated shears (UAS) observed in thyroidectomies in a previous matched-pair study could be repeated in a randomized trial. SUMMARY BACKGROUND DATA: The UAS has been documented, mainly in nonrandomized studies, to be a safe and fast device in video-assisted and conventional surgery. METHODS: Thyroidectomies and lobectomies performed for benign or malignant thyroid disease between August 1997 and January 1999 were included in this series. Separate randomization, resulting in four sets of envelopes, was done for one consultant endocrine surgeon and for senior residents for both lobectomies and for total thyroidectomies. The operations performed with the UAS were compared with operations performed with the conventional method, using ligatures as the main hemostatic method. Main outcome measures were operating time, postoperative serum calcium level, palsy of the recurrent laryngeal nerve, and amount of intraoperative and postoperative bleeding. Possible bias that could have been caused by imbalance between treatment groups for surgeon experience was tested by two-way analysis of covariance. RESULTS: Thirty-six patients were randomized, 19 to the UAS and 17 to the conventional group. Mean operating time was 99.1 minutes in the UAS group and 134.9 minutes in the conventional group. The average savings in operating time with the UAS was thus 35.8 minutes. There was no difference in complications between the groups. The estimated savings in operating time would have been 1.66 times that observed in this study if the groups had been unbalanced with reference to surgeon experience. CONCLUSION: The UAS is a usable device in total thyroidectomies and lobectomies.  相似文献   
19.
Climate change would have a range of impacts on human health. Health impacts would be caused by the direct effect of climatic factors on human health, such as heat stress, and possible changes in the frequency and intensity of extreme weather events such as storms, floods and droughts. Impacts on health would also be mediated by the indirect effects of climate change, such as changes in availability of food and water and the distribution of vector‐borne diseases. The majority of health impacts would be adverse and would depend greatly on the vulnerability of populations.  相似文献   
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