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排序方式: 共有1337条查询结果,搜索用时 78 毫秒
1.
Arti Nanda Hanan Al‐Abboh Akmal Zahra Humoud Al‐Sabah Arun Gupta Adekunle D. Adekile 《Pediatric dermatology》2019,36(2):258-259
Neutrophilic panniculitis (NP) with myelodysplasia has been described in adults but not in children. We report a case of NP associated with myelodysplasia in a child with MYSM1 deficiency, a newly described syndrome with primary immunodeficiency (PI), bone marrow failure, and developmental aberrations. 相似文献
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3.
Shwikar AbdelSalam Ahmed Azza Mahmoud Elhefnawy Hanan Galal Azouz Yara Safwat Roshdy Mona Hamdy Ashry Ahmed Elsayed Ibrahim Marwa Ahmed Meheissen 《Journal of molecular neuroscience : MN》2020,70(6):887-896
The role of gut microbiome was recently raised in the pathogenesis of neurodevelopmental disorders including autism spectrum disorder (ASD). The aim of this study was to elucidate changes in gut microbiome in Egyptian autistic children and its possible correlation with the severity of autism and gastrointestinal (GI) symptoms. The gut bacterial microbiome of 41 ASD children, 45 siblings, and 45 healthy controls were analyzed using quantitative SYBR Green real-time PCR technique targeting 16S rRNA of selected bacteria. The gut microbiome of ASD children and their siblings contained a higher relative abundance of Bacteroides as well as Ruminococcus than controls. Prevotella/Bacteroides (P/B) ratio and Firmicutes/Bacteroidetes (F/B) were significantly lower in both ASD cases and their siblings. The only difference between the autistic cases and their siblings was the significantly higher level of Bifidobacterium in siblings, which appears to offer them a protective role. There was no correlation between the altered gut microbiome and the severity of autism or GI symptoms. The current study showed an evidence of changes in the gut microbiome of autistic children compared to the unrelated control. However, the microbiome profile of siblings was more like that of autistic children than that of unrelated controls indicating that gut microbiota is affected by dietary habits, living conditions together with host genetic factors. 相似文献
4.
Rebecca Wright Caleb Ferguson Mustafa Bodrick Hanan Balkhy Debra Jackson Patricia M. Davidson 《Journal of clinical nursing》2020,29(13-14):2723-2729
5.
Bassem M. Salama Wafaa A. Helmy Tamer I. M. Ragab Mamdouh M. Ali Hanan A. A. Taie Mona A. Esawy 《Journal of basic microbiology》2019,59(10):1004-1015
Screening of 18 bacterial honey isolates revealed that all the isolates were levansucrase producers. The most potent isolate that achieved the highest activity (45.66 U/ml) was identified as Bacillus subtilis NRC based on morphological examination and 16S rRNA. The results recorded the necessity of starch (5 g/L), baker's yeast (12.5 g/L), and AlCl3 (5 mM) in improvement of the enzyme productivity. The Bacillus subtilis levansucrase was eluted as a single protein in one purification step. The enzyme molecular weight was (14 kDa). It showed its optimum activity at 45°C and could retain 60% of its activity after incubation at 50°C for 2 h. Its optimum activity was obtained at pH 8.2 and the enzyme showed great pH stability in both acidic and alkaline ranges. Unlike, most levansucrases all tested metals had an adverse effect in enzyme activity. The enzyme had antioxidant activities and were characterized as spherical micro‐ and nanoparticles by transmission electron microscopy. The effect of growth conditions and medium composition in levan structure and its fibrinolytic activity was evaluated. 相似文献
6.
Atteeq U. Rehman Maryam Najafi Marios Kambouris Lihadh Al‐Gazali Periklis Makrythanasis Abolfazl Rad Reza Maroofian Anna Rajab Zornitza Stark Jill V. Hunter Zeineb Bakey Mari J. Tokita Weimin He Francesco Vetrini Andrea Petersen Federico A. Santoni Hanan Hamamy Kaman Wu Fatma Al‐Jasmi Martin Helmstdter Sebastian J. Arnold Fan Xia Christopher Richmond Pengfei Liu Ehsan Ghayoor Karimiani GholamReza Karami Madani Sebastian Lunke Hatem El‐Shanti Christine M. Eng Stylianos E. Antonarakis Jozef Hertecant Magdalena Walkiewicz Yaping Yang Miriam Schmidts 《Human mutation》2019,40(3):267-280
Next‐generation sequencing (NGS) has been instrumental in solving the genetic basis of rare inherited diseases, especially neurodevelopmental syndromes. However, functional workup is essential for precise phenotype definition and to understand the underlying disease mechanisms. Using whole exome (WES) and whole genome sequencing (WGS) in four independent families with hypotonia, neurodevelopmental delay, facial dysmorphism, loss of white matter, and thinning of the corpus callosum, we identified four previously unreported homozygous truncating PPP1R21 alleles: c.347delT p.(Ile116Lysfs*25), c.2170_2171insGGTA p.(Ile724Argfs*8), c.1607dupT p.(Leu536Phefs*7), c.2063delA p.(Lys688Serfs*26) and found that PPP1R21 was absent in fibroblasts of an affected individual, supporting the allele's loss of function effect. PPP1R21 function had not been studied except that a large scale affinity proteomics approach suggested an interaction with PIBF1 defective in Joubert syndrome. Our co‐immunoprecipitation studies did not confirm this but in contrast defined the localization of PPP1R21 to the early endosome. Consistent with the subcellular expression pattern and the clinical phenotype exhibiting features of storage diseases, we found patient fibroblasts exhibited a delay in clearance of transferrin‐488 while uptake was normal. In summary, we delineate a novel neurodevelopmental syndrome caused by biallelic PPP1R21 loss of function variants, and suggest a role of PPP1R21 within the endosomal sorting process or endosome maturation pathway. 相似文献
7.
Ayelet Rosenthal Stephanie B. Oliveira Uche Madubuko Hanan Tanuos Joseph Schwab Iona M. Monteiro 《Journal of the National Medical Association》2019,111(2):153-157
ObjectiveInfant feeding practices have been shown to differ between immigrants and non-immigrants in the United States. Our study characterizes feeding practices of infants of immigrant versus American-born mothers followed in an inner city Pediatric continuity clinic serving predominantly low socioeconomic status families.MethodsA survey was given to 102 parents of infants ranging from 12 to 15 months of age who attended the clinic. Parents were asked about their country of origin, ethnic background and time since immigration to the US. They were also asked about their breastfeeding and early infant feeding practices. Statistical significance was estimated using chi-squared tests.ResultsNot only were breastfeeding rates higher among immigrant mothers compared to American-born mothers (88% vs. 63%, p-value 0.008) but they introduced commercially available baby food less frequently (37% vs. 52%, p-value 0.03) and rarely fed their infants fast food (22% vs. 50%, p-value<0.001). Moreover, breast feeding rates decreased with duration of residence in the United States. 53% of immigrant mothers who have been in the United States for less than 5 years breastfed for over 6 months versus 22% of immigrant mothers who resided more than 5 years in the United States (p-value 0.02). The vast majority of immigrant mothers who switched to formula did so because they felt their milk production was insufficient (93%) whereas the vast majority of American-born mothers stopped breastfeeding because they perceived it to be painful (64%, p value 0.001).ConclusionsInfant feeding practices differ between immigrant and American-born mothers and the differences diminish the longer the mothers reside in the United States. These differences stem from differences in cultural perceptions of breastfeeding. Therefore, in educating mothers about infant feeding, physicians should strongly consider cultural and ethnic factors. 相似文献
8.
Hanan El Marroun Tonya White Frank C. Verhulst Henning Tiemeier 《European child & adolescent psychiatry》2014,23(10):973-992
Antidepressant and anxiolytic medications are widely prescribed and used by pregnant women for acute and maintenance therapy. These drugs are able to pass the placental barrier, and may potentially influence fetal and brain development. It is possible that exposure to prenatal antidepressants or anxiolytic medication may disturb neurotransmitter systems in the brain and have long-lasting consequences on neurodevelopment in the offspring. As all medication during pregnancy may pose a certain risk to the developing fetus, the potential benefits of the medication must be weighed against the risks for both mother and her unborn child. Therefore, information to guide patients and physicians to make a well-balanced decision for the appropriate treatment during pregnancy is needed. In this systematic review, an overview of maternal use of antidepressant or anxiolytic medication during pregnancy and childhood neurodevelopmental outcomes is provided. Some studies indicate a relation between prenatal exposure to antidepressants and adverse neurodevelopmental outcomes such as delayed motor development/motor control, social difficulties, internalizing problems and autism, but cannot rule out confounding by indication. Overall, the results of the observational studies have been inconsistent, which makes translation of the findings into clinical recommendations difficult. More well-designed observational studies and also randomized controlled trials (e.g., maintenance treatment vs. cessation) are needed to move forward and provide a comprehensive evaluation of the risks and benefits of antidepressant and anxiolytic use during pregnancy. 相似文献
9.
Bassam Bernieh Samra Abouchacra Yousef Boobes Mohammad R. Al Hakim Nico Nagelkerke Ahmad Chaaban Mohamad Ahmed Qutaiba Hussain Hanan El Jack Faiz Abayechi Imran Khan Nicole Gebran 《International urology and nephrology》2014,46(2):453-459
Purpose
Maintaining target hemoglobin (Hb) with minimal variability is a challenge in hemodialysis (HD) patients. The aim of this study is to compare the long- and short-acting erythropoietin-stimulating agents such as Aranesp and Eprex in achieving these targets.Methods
Randomized, prospective, open-labeled study of 24 weeks includes stable patients on HD >3 months, age >18 years, and on Eprex for >3 months. Patients were randomized into two groups: A-(Aranesp group):HD patients on Eprex Q TIW or BIW were converted to Aranesp Q weekly, by using the conversion factor of 200:1 and those on Eprex Q weekly to Aranesp Q 2 weeks; B-(Eprex group):patients continued on Eprex treatment. Hemoglobin target was set at (105–125 g/l). Primary end points were percentage of patients achieving target Hb, hemoglobin variability, and number of dose changes in each group.Results
This study consisted of 139 HD patients: 72 in the Aranesp and 67 in the Eprex—mean (SD) age 54 (16.2) years, 77 (55 %) males. About 46 % were diabetic. Target Hb achieved in 64.8 % of the Aranesp and 59.7 % in the Eprex (p = 0.006). Hb variability was less frequent in the Aranesp group (p = 0.2). Mean number of dose changes was 1.3 (0.87) in the Aranesp and 1.9 (1.2) in the Eprex (p < 0.001). There was 1 vascular access thrombosis in the Aranesp and 8 in the Eprex (p < 0.001). There was no difference in hospitalization and death number between the 2 groups.Conclusions
Aranesp Q weekly or every 2 weeks is more efficient in achieving target Hb, with less dose changes and minor vascular access complications. 相似文献10.
Gerbrich E. van den Bosch Hanan El Marroun Marcus N. Schmidt Dick Tibboel Dara S. Manoach Vince D. Calhoun Tonya J.H. White 《Human brain mapping》2014,35(2):698-711
Working memory (WkM) is a fundamental cognitive process that serves as a building block for higher order cognitive functions. While studies have shown that children and adolescents utilize similar brain regions during verbal WkM, there have been few studies that evaluate the developmental differences in brain connectivity. Our goal was to study the development of brain connectivity related to verbal WkM in typically developing children and adolescents. Thirty‐five healthy children and adolescents, divided into three groups: 9–12 (children), 13–16 (young adolescents), and 17–19 (older adolescents) years, were included in this functional magnetic resonance imaging (fMRI) study. The verbal WkM task involved a modified Sternberg item recognition paradigm using three different loads. Brain connectivity analysis was performed using independent component analyses and regressing the components with the design matrix to determine task‐related networks. Connectivity analyses resulted in four components associated solely with encoding, four solely with recognition and two with both. Two networks demonstrated age‐related differences with respect to load, (1) the left motor area and right cerebellum, and 2) the left prefrontal cortex, left parietal lobe, and right cerebellum. Post hoc analyses revealed that the first network showed significant effects of age between children and the two older groups. There was increasing connectivity with increasing load for adolescents. The second network demonstrated age‐related differences between children and older adolescents. Children have higher task‐related connectivity at lower loads, but they tend to equalize with the adolescents with higher loads. Finally, a non‐load related network involving the orbital frontal and anterior cingulate cortices showed less connectivity in children. Hum Brain Mapp 35:698–711, 2014. © 2012 Wiley Periodicals, Inc. 相似文献