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101.
Idiopathic basal ganglia calcification (IBGC) is a rare neuropsychiatric disorder characterized by bilateral and symmetric cerebral calcifications. Recently, SLC20A2 was identified as a causative gene for familial IBGC, and three mutations were reported in a northern Chinese population. Here, we aimed to explore the mutation spectrum of SLC20A2 in a southern Chinese population. Sanger sequencing was employed to screen mutations within SLC20A2 in two IBGC families and 14 sporadic IBGC cases from a southern Han Chinese population. Four novel mutations (c.82G > A p.D28N, c.185T > C p.L62P, c.1470_1478delGCAGGTCCT p.Q491_L493del and c.935-1G > A) were identified in two families and two sporadic cases, respectively; none were detected in 200 unrelated controls. No mutation was found in the remaining 12 patients. Different mutations may result in varied phenotypes, including brain calcification and clinical manifestations. Our study supports the hypothesis that SLC20A2 is a causative gene of IBGC and expands the mutation spectrum of SLC20A2, which facilitates the understanding of the genotype–phenotype correlation of IBGC.  相似文献   
102.

Objectives

Progressive dementia is a rare phenotypic feature of female X-ALD carriers. Even rarer is the additional presence of further risk factors for dementia, such as diabetes, hypothyroidism, and hepatopathy. We report a unique female X-ALD carrier presenting with severe, progressive dementia, paraspasticity, sphincteric dysfunction, and multisystem disease.

Case report

A 79 years-old female with a history of strumectomy, diabetes, hepatopathy, hypothyroidism, arterial hypertension, hiatal hernia, left retinal ablation, ovariectomy, hysterectomy, osteoporosis, bilateral hip endoprosthesis, and neurogenic bladder dysfunction developed slowly progressive cognitive decline since age of 77 years. She had been identified as a female carrier of X-ALD in 12/2010 upon a family screening. At age of 79 years she presented with severe dementia, anxiety, unsteadiness, helplessness, hypertelorism, exaggerated patella tendon reflexes, reduced Achilles tendon reflexes, club feet, contractures of the ankles, the knees, and the hips, and the inability to stay or walk. Cerebral CT showed diffuse atrophy, demyelination periventricularly, small lacunas in the basal ganglia, and small calcifications of the basal ganglia and the temporal lobe on the right side. Differential diagnoses of dementia were considered but were all excluded upon the clinical presentation, blood chemical investigations, imaging studies, and the pattern of neuropsychological deficits.

Conclusions

With progression of the disease manifesting X-ALD carriers may develop progressive severe dementia, severe paraspasticity, and sphincteric dysfunction. Female carriership of X-ALD can be a differential diagnosis of dementia.  相似文献   
103.
《Anthrozo?s》2013,26(1):25-42
Abstract

A conceptual model was developed to describe the dynamics of the pet dog population. The model synthesizes existing data collected for a variety of purposes to estimate the size of the various components of the pet dog population in Washington and Iowa during 1991. The total population mortality rate was estimated as 12.4% per year. Animal shelters in Washington and Iowa handled 7.6% and euthanized 4.0% of the dog population in those two states. When these estimates were extrapolated to the entire U.S. dog population, the model predicted that the total annual turnover in owned dogs was 14.7%, or 7.71 million dogs, that 4 million dogs were handled by animal shelters, and that 2.1 million were euthanized. It was also estimated that 79% of all female dogs were spayed, that household breeding could be attributed to less than one-fifth (18.7%) of the female dogs in the reproductive pool, and that the number of owners contributing to total dog population turnover through failure to retain their dog (103,453) was approximately three times the number of owners who allowed their female dogs to be bred (32,513).  相似文献   
104.
Abstract

The blood pool is among body compartments of a special interest for imaging using magnetic resonance (MR) and computed tomography (CT), since with the help of selective blood-pool contrast agents blood perfusion and various cardiac parameters as well as a status of the blood flow and vascular system in any organ can be evaluated. Blood pool-specific imaging agents can also provide minimally invasive angiography, image guidance of minimally invasive procedures, oncologic imaging of angiogenesis, ascertaining organ blood volume, and identifying hemorrhage. Particulate contrast agents (such as liposomes and micelles) whose distribution is limited to the blood pool, should have a size larger than fenestrated capillaries (> 10 nm), contain the reporter (paramagnetic or radiopaque) moiety structurally incorporated within the particulate, and be able to stay in the blood long enough to obtain clinically useful images. We describe here a new generation of long-circulating Gd-loaded liposomes and iodine-loaded micelles to provide an efficient blood pool MR and CT imaging, respectively. In this study, we developed the optimized protocol to prepare a liposomal MR contrast agent with high relaxivity and narrow size distribution. Liposomes were loaded with Gadolinium (Gd) via so called polychelating amphiphilic polymer (PAP) that represents a low-molecular-weight DTPA-polylysine linked via its N-terminus to a lipid anchor, NGPE-PE. Gd-containing liposomes were additionally modified with PEG to provide the longevity in vivo. We demonstrated also that upon the intravenous administration in rabbits and dogs, a new preparation causes prolonged decrease in the blood Tl value, permits to obtain sharp and clear MR images of the vasculature, and may be considered as a potential contrast agent for MRI of the blood pool. In addition, to prepare micellar contrast agents for CT blood-pool imaging, we synthesized an iodine-containing amphiphilic block-copolymer consisting of methoxypoly(ethyleneglycol) and polyl?,N-(triiodobenzoyl)]-L-lysine. In aqueous solutions, it forms stable micelles with an average diameter of 80 nm and an iodine content of 35–40% wt. Iodine-containing micelles were intravenously injected into rats and rabbits at a dose of 170 mg I/kg and produced significant and sustained enhancement of the blood pool (aorta and heart), liver and spleen for a period of at least 3 hours providing clear and informative CT images.  相似文献   
105.
Nanomaterials with superior physiochemical properties have been rapidly developed and integrated in every aspect of cell engineering and therapy for translating their great promise to clinical success. Here we demonstrate the multifaceted roles played by innovatively-designed nanomaterials in addressing key challenges in cell engineering and therapy such as cell isolation from heterogeneous cell population, cell instruction in vitro to enable desired functionalities, and targeted cell delivery to therapeutic sites for prompting tissue repair. The emerging trends in this interdisciplinary and dynamic field are also highlighted, where the nanomaterial-engineered cells constitute the basis for establishing in vitro disease model; and nanomaterial-based in situ cell engineering are accomplished directly within the native tissue in vivo. We will witness the increasing importance of nanomaterials in revolutionizing the concept and toolset of cell engineering and therapy which will enrich our scientific understanding of diseases and ultimately fulfill the therapeutic demand in clinical medicine.  相似文献   
106.
107.
The transformation efficiency of naturally competent Bacillus subtilis cells can be significantly increased using β recombinase binding sequences, as revealed by the results of this study. Plasmids containing different variations of these so called six-site-marker-cassettes were investigated. Furthermore, an optimized protocol for knock-out or knock-in mutations combining the Cre–lox-system and the six-sites is presented, which can be used for multiple genome modifications of B. subtilis.  相似文献   
108.
109.
The phycobilisome (PBS) is a photosynthetic light-harvesting complex in red algae, whose structural genes are separately encoded by both the nuclear and chloroplast genomes. While the expression of PBS genes in both genomes is responsive to environmental changes to modulate light-harvesting efficiency, little is known about how gene expression of the two genomes is coordinated. In this study, we focused on the four nuclear-encoded chloroplast sigma factors to understand aspects of this coordination, and found that SIG2 directs the expression of chloroplast PBS genes in the red alga Cyanidioschyzon merolae.  相似文献   
110.
IntroductionBronchiectasis is a chronic disease of the lungs by repeated respiratory infection. An early and adequate diagnosis and management reduce the morbidity and mortality of this disease. The aim of this study is to emphasize the importance of the combination of Computer Tomography (CT) and lung perfusion scan (SPP) in the diagnosis and therapeutic approach.Materials and methodsForty-three children were referred in the nuclear medicine department with a clinical diagnosis of bronchiectasis; they underwent a CT and a SPP.Results and conclusionBy analyzing the results of the SPP and CT separately, we conclude that there is no significant difference between the two investigations. The combination of the two explorations provides a gain in most surgical therapeutic orientation.  相似文献   
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