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91.
92.
Hypoplastic left heart syndrome remains one of the most challenging pathologies in pediatric cardiac surgery. The surgical techniques, and anesthetic and intensive care management, have evolved over the last decades, which has resulted in improved outcomes. A central component in the postoperative management of hypoplastic left heart syndrome patients is to achieve an optimal balance between the pulmonary and systemic circulations. This article discusses the contemporary postoperative management of pulmonary and systemic circulations in detail.  相似文献   
93.

Purpose

Desmoplastic infantile gangliogliomas (DIGs) are rare tumors of infancy. Herein, we describe an unusual case of DIG diagnosed by prenatal ultrasound.

Methods

This 5-day-old newborn was delivered after a prenatal ultrasound revealed a large cystic mass in the left cerebral hemisphere along with an echogenic solid component.

Results

The tumor revealed a glial and neuronal proliferation in a background of desmoplasia more typical of DIG and a minor component with a more primitive, immature appearance to the glioneuronal elements. A significant component of the tumor was composed of pleomorphic eosinophilic spindle cells in whorls and interlacing fascicles that showed a strong, sharp, and diffuse positivity for desmin, thus mimicking rhabdomyosarcoma. However, the tumor cells were GFAP (+), INI-1 (+), and myogenin (?). Mitoses were seen both in the more spindle cell astroglial areas as well as the more primitive neuroepithelial cells. The MIB-1 proliferation index was brisk, exceeding 15 %, and in areas it was estimated to be as high as 30 %. Such high proliferation index has been described and accepted in the more primitive neuroepithelial areas, but not in the terminally differentiated, spindle cell astroglial areas as in our case. Our patient was incidentally diagnosed prenatally. To our knowledge, this case is the first documented congenital DIG diagnosed prenatally.

Conclusions

This case highlights the pitfalls in diagnosing DIG, which can mimic a rhabdomyosarcoma. Furthermore, it underscores the importance of re-evaluating the grading of these tumors or at least segregating the variants where the prognosis may be more guarded.  相似文献   
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95.
Background Until now, segmental vitiligo has been considered as a stable entity and mixed vitiligo, the association of segmental and nonsegmental vitiligo, has been reported rarely. Objectives The aim of this study was to search for factors associated with the generalization of vitiligo in patients with segmental vitiligo. Patients and methods This was a prospective observational study conducted in the vitiligo clinic of the Department of Dermatology of Bordeaux, France. The Vitiligo European Task Force questionnaire was completed for each patient attending the clinic with a confirmed diagnosis of segmental vitiligo after exclusion of other forms of vitiligo (focal, mucosal, not classifiable.) Thyroid function and antithyroid antibodies were screened if not obtained in the previous year. Results One hundred and twenty‐seven patients were recruited: 101 had segmental vitiligo and 26 had segmental vitiligo that evolved into mixed vitiligo; 56 were male and 71 were female. Most patients had onset of segmental vitiligo before the age of 18. When conducting multivariate analysis, we found the following to be independent factors associated with the evolution of patients’ disease from segmental vitiligo to mixed vitiligo: initial percentage of body surface involvement of the segment > 1% [odds ratio (OR) 15·14, P = 0·002], the presence of halo naevi (OR 24·82, P = 0·0001) and leukotrichia (OR 25·73, P = 0·0009). Conclusions Halo naevi association and leukotrichia at first consultation in segmental vitiligo are risk factors for the progression of segmental vitiligo to mixed vitiligo. In addition, this progression of segmental vitiligo to mixed vitiligo carries a stronger link if initial segmental involvement is situated on the trunk.  相似文献   
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97.
Neurothekeoma is a rare neoplasm assigned to the broad category of benign peripheral nerve sheath tumors. Its cell of origin is still unknown, but most ultrastructural and immunohistochemical studies have favoured the Schwann cell perineurium or fibroblast. Neurothekeoma most commonly presents in females, especially in the second and third decades of life. Typically it presents as an asymptomatic solitary, firm, flesh-coloured or hyperpigmented slow-growing papule or nodule that involves the skin and superficial subcutis. It usually involves the face, neck, arm or shoulder but can also involve extracutaneous sites. Neurothekeoma occurs in myxoid (classic), cellular and intermediate (mixed) variants. Here, we report a 45-year-old male patient presenting with a nodule on the nose that was found to be a myxoid variant of neurothekeoma. It was treated with a simple shave excision followed by removal of the lobulated deeper part by forceps. He had no recurrence after three years of follow-up. To the best of our knowledge, this is the first case of a myxoid neurothekeoma of the nose to be reported in the Middle East.  相似文献   
98.
The main objective of this study was to evaluate CYP2C19 genetic polymorphism in a Saudi Arabian population by determining the frequencies of CYP2C19*2, *3, *4, *6, *7 and *17 alleles and their relevant genotypes. Genomic DNA was isolated from 192 healthy Saudi Arabians, representing different geographical regions, and genotyping of the selected CYP2C19 variants was carried out by direct sequencing after PCR amplification. The allelic frequency of heterozygous CYP2C19*2 was 8.2% with only one individual found to carry the homozygous genotype of this defective allele. None of the other investigated poor metabolizer alleles (i.e. CYP2C19*3, *4, *6 and *7) was detected in the study population. About 46% of the examined volunteers were found to carry CYP2C19*17 genotype (37.5% heterozygous and 8.1% homozygous of the defective allele) with an overall CYP2C19*17 allelic frequency of 26.9%. In addition, a novel CYP2C19 SNP (G356A) and another very rare SNP (C336T) have been identified in this study with a frequency of about 50% for each. Further studies are required to evaluate the metabolic and clinical relevance of CYP2C19*17, G356A and C336T in the Saudi Arabian population.  相似文献   
99.
Chronic kidney disease (CKD) is known to cause increased arterial stiffness, which is an important independent risk factor for adverse cardiovascular events. The purpose of this study was to assess the vascular properties of the aorta (AO) in a group of children with CKD using a noninvasive echocardiography (echo)-Doppler method. We studied 24 children with stages 2 through 5 CKD and 48 age-matched controls. Detailed echocardiographic assessment and echo-Doppler pulse wave velocity (PWV) was performed. Indices of arterial stiffness, including characteristic (Zc) and input (Zi) impedances, elastic pressure-strain modulus (Ep), and arterial wall stiffness index, were calculated. CKD patients underwent full nephrology assessment, and an iohexol glomerular filtration rate was performed, which allowed for accurate assignment of the CKD stage. CKD patients had greater median systolic blood pressure (114 vs. 110 mmHg; p < 0.04) and pulse pressure (51 vs. 40 mmHg; p < 0.001) compared with controls. PWV was similar between groups (358 vs. 344 cm s?1; p = 0.759), whereas Zi (182 vs. 131 dyne s cm?5; p < 0.001), Zc (146 vs. 138 dyne s cm?5; p = 0.05), and Ep (280 vs. 230 mmHg; p < 0.02) were significantly greater in CKD than in controls. Although load-dependent measures of arterial stiffness were greater in non-dialysis dependent CKD patients, PWV was not increased compared with controls. This suggests that the increased arterial stiffness may not be permanent in these pediatric patients with kidney disease.  相似文献   
100.
Background: Osteoporosis is a frequent human metabolic bone disorder. Prospectively, global ageing of populations will lead to a major increase of subjects being diagnosed with osteoporosis and in need for dental rehabilitation. However, as local osteoporosis of the jaws affects bone quantity and quality of edentulous regions, osseointegration of dental implants might be hampered. Consequently, calcium phosphate ceramic-coated implants have been suggested to compensate for low bone quantity/density and for impaired bone healing in osteoporosis. Nonetheless, up to now no meta-analytical assessment of the relevant preclinical literature to quantify such a possible positive effect has been undertaken. Materials and Methods: PubMed search, limited to animal models, to identify a possible positive effect of calcium phosphate-coated implants on bone regeneration, was carried out. Further, the reference lists of related review articles and publications selected for inclusion in this review were systematically screened. The primary outcome variables were bone-to-implant contact percentage as assessed histomorphometrically and mechanical stability testing. Results: The electronic search in the database of the National Library of Medicine resulted in the identification of 2704 titles. These titles were initially screened by the two independent reviewers for possible inclusion, resulting in further consideration of 51 publications. Screening the abstracts led to 22 full-text articles. From these articles, 16 reports were excluded. Finally, six of these original research reports could be selected for evaluation. Additionally, eight publications were identified by manual search. Thus, a total of 14 articles were included for analysis. Conclusions: It was concluded that (1) in osteoporotic animal models calcium phosphate ceramic-coated implants are associated with improved bone-to-implant healing as compared to noncoated implants. Moreover, (2) essentially due to quality characteristics of the analyzed original research articles a negative impact of osteoporosis on bone-to-implant healing could not be confirmed. Besides, (3) the established positive bone-to-implant healing effect of calcium phosphate ceramic coatings does not differ between osteoporotic and nonosteoporotic, healthy animal models.  相似文献   
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