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21.
Diego A. Gomez Lynne M. Bird Nicole Fleischer Omar A. Abdul‐Rahman 《American journal of medical genetics. Part A》2020,182(9):2021-2026
Angelman syndrome (AS) is caused by several genetic mechanisms that impair the expression of maternally‐inherited UBE3A through deletions, paternal uniparental disomy (UPD), UBE3A pathogenic variants, or imprinting defects. Current methods of differentiating the etiology require molecular testing, which is sometimes difficult to obtain. Recently, computer‐based facial analysis systems have been used to assist in identifying genetic conditions based on facial phenotypes. We sought to understand if the facial‐recognition system DeepGestalt could find differences in phenotype between molecular subtypes of AS. Images and molecular data on 261 individuals with AS ranging from 10 months through 32 years were analyzed by DeepGestalt in a cross‐validation model with receiver operating characteristic (ROC) curves generated. The area under the curve (AUC) of the ROC for each molecular subtype was compared and ranked from least to greatest differentiable phenotype. We determined that DeepGestalt demonstrated a high degree of discrimination between the deletion subtype and UPD or imprinting defects, and a lower degree of discrimination with the UBE3A pathogenic variants subtype. Our findings suggest that DeepGestalt can recognize subclinical differences in phenotype based on etiology and may provide decision support for testing. 相似文献
22.
Peiwen Pan Mari Leppilampi Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S. Sly Seppo Parkkila 《The Journal of physiology》2006,571(2):319-327
Using real-time PCR and immunohistochemistry, we have examined the expression of carbonic anhydrase isozymes (CA) I, II, III, IV, IX, XII, XIII and XIV in the brain, kidney, stomach and colon of the wild-type, CA II-deficient ( Car2−/− ), and CA IX deficient ( Car9−/− ) mice. The expression of Car4, Car12, Car13 and Car14 mRNAs did not show any significant deviations between the three groups of mice, whereas both groups of CA deficient mice showed decreased expression levels of Car1 in the colon and Car3 in the kidney. The Car2 mRNA level was greatly reduced but not completely abolished in all four tissues from the Car2−/− mice in which no CA II protein was expressed. Sequencing the Car2 cDNA isolated from C57BL6 Car2−/− mice revealed two nucleotide differences from the wild-type C57BL6 mice. One is a silent polymorphism found in Car2 mRNA from wild-type DBA mice, which is the strain that provided the original mutagenized chromosome. The second change is a mutation that causes prematurely terminated translation at codon 155 (Gln155X). Car9 mRNA and CA IX protein expression levels were up-regulated about 2.5- and 3.6-fold, respectively, in the stomach of the Car2−/− mice. These results suggest that the loss of function of cytosolic CA II in the stomach of Car2−/− mice leads to up-regulation of an extracellular CA, namely CA IX, which is expressed on the cell surface of the gastric epithelium. 相似文献
23.
Abdul A. Hassoni Peter T. A. Gray 《Pflügers Archiv : European journal of physiology》1994,428(3-4):269-274
The control of Cl– conductance in rat parotid isolated acinar cells was studied by combined use of whole-cell recording and flash photolysis techniques. Cells were voltage-clamped either at a membrane potential of –40 mV or stepped between –85 mV and 0 mV. Bath-applied carbachol and noradrenaline evoked Cl– current at –85 mV and K+ current at 0 mV. Similar current activations resulted from the photolytic release of either inositol trisphosphate (InsP
3) or Ca2+ by a brief near-UV flash. The peak amplitudes of the Cl– conductance (at –85 mV), measured relative to the K+ conductance (at 0 mV), evoked by application of carbachol, noradrenaline or direct manipulation of cytosolic free calcium ([Ca2+]i), were very similar, being 0.56±0.09 (mean±SEM,n=9), 0.52 ± 0.01 (n=7) and 0.46±0.06 (n=7). In contrast, the relative amplitude of the Cl– conductance evoked by InsP3 was much larger: 1.49±0.24 (n=9). Neither bath application of isoprenaline nor photolysis of caged cAMP induced any detectable membrane current. The most probable interpretation of these results is that the observed activation of Cl– conductance by agonists can be explained by the elevation of [Ca2+]i alone. In addition, the present results provide further support for the previously reported suggestion that the Cl– channels and the Ca2+-release sites are co-localised [10]. 相似文献
24.
IL-1 and TNF independent pathways mediate ICAM-1/VCAM-1 up-regulation in ischemia reperfusion injury 总被引:16,自引:0,他引:16
Burne MJ Elghandour A Haq M Saba SR Norman J Condon T Bennett F Rabb H 《Journal of leukocyte biology》2001,70(2):192-198
In vitro studies have suggested that targeting interleukin (IL)-1 and tumor necrosis factor (TNF) can be used to regulate intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and potentially treat kidney inflammation. We therefore evaluated ICAM-1 and VCAM-1 regulation in knockout (KO) mice deficient in both IL-1 receptor 1 (R1) and TNF-R1 during renal ischemia reperfusion injury. ICAM-1 and VCAM-1 mRNA expression was measured with specific murine probes and Northern blotting (n =4/group). Protein expression was measured using immunohistochemistry. Serum creatinine (SCr), tubular histology, and neutrophil infiltration into postischemic kidneys were also quantified. ICAM-1 and VCAM-1 mRNA expression increased in both wild-type (WT) and KO mice at 2, 6, and 24 h. Protein expression of ICAM-1 and VCAM-1 was also increased at 24 h postischemia. SCr levels and tubular necrosis scores were comparable in WT and KO mice at 24 and 48 h. Neutrophil migration in KO mice was decreased at 24 h but comparable to WT at 48 h. These data demonstrate that IL-1 and TNF are not essential for postischemic increases in ICAM-1 and VCAM-1. 相似文献
25.
Saheki T Kobayashi K Iijima M Horiuchi M Begum L Jalil MA Li MX Lu YB Ushikai M Tabata A Moriyama M Hsiao KJ Yang Y 《Molecular genetics and metabolism》2004,81(Z1):S20-S26
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues. 相似文献
26.
Susceptibility pattern and molecular type of species-specific Candida in oropharyngeal lesions of Indian human immunodeficiency virus-positive patients
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Lattif AA Banerjee U Prasad R Biswas A Wig N Sharma N Haque A Gupta N Baquer NZ Mukhopadhyay G 《Journal of clinical microbiology》2004,42(3):1260-1262
A study of oropharyngeal candidiasis (OPC) in Indian human immunodeficiency virus (HIV)/AIDS patients was conducted over a period of 15 months. This study revealed that 75% of the HIV/AIDS patients had OPC. MIC testing revealed that 5% of the Candida isolates were fluconazole resistant. A correlation between CD4(+)-T-cell counts and development of OPC in HIV/AIDS patients was also observed. Molecular typing of C. albicans isolates showed that all were genetically unrelated. 相似文献
27.
28.
The effect of gamma interferon on IL-1 secretion of in vitro differentiated human macrophages 总被引:4,自引:0,他引:4
After being cultured overnight, human monocytes lose their ability to secrete interleukin-1 (IL-1) when stimulated by lipopolysaccharide (LPS). However, when these monocytes were cultured for up to 9 days with various concentrations of interferon-gamma (IFN-gamma), these cells were found to retain their ability to secrete appreciable amounts of IL-1 on LPS stimulation. However, the effect was observed only if the monocytes were exposed to the IFN before LPS stimulation and simultaneous addition of IFN and LPS to macrophages was ineffective. This effect of IFN-gamma was related to the concentration of IFN added to the cultures and was completely neutralized by a monoclonal antibody to IFN-gamma. In addition to inducing IL-1 secretion, IFN-gamma also appeared to increase the overall production of IL-1, since reinduction of IL-1 secretion was not associated with a decrease in intracellular IL-1 content. When these macrophages were initially cultured with IFN-gamma, washed, and further cultured with IFN free medium, these macrophages were found to progressively lose their capacity to secrete IL-1 in response to LPS. Conversely, when monocytes were initially cultured in medium free of IFN, washed, and then further cultured in new medium, but now containing IFN-gamma, these macrophages were found to regain their capacity to secrete IL-1. However, the amount of reinduced IL-1 secretion decreased as the length of the initial culture period without IFN increased, with less than optimal IL-1 secretion occurring if monocytes were allowed to mature for 6 days before IFN-gamma pretreatment. In summary, these studies suggest that IFN-gamma may be important in enhancing IL-1 production and secretion by maturing macrophages and tissue macrophages and consequently may play a role in regulating the accessory cell activity of these cells for a variety of immune responses in vivo. 相似文献
29.
30.
Benedict Wei Jun Pang Shiou-Liang Wee Lay Khoon Lau Khalid Abdul Jabbar Wei Ting Seah Daniella Hui Min Ng Queenie Lin Ling Tan Kenneth Kexun Chen Mallya Ullal Jagadish Tze Pin Ng 《Journal of the American Medical Directors Association》2021,22(4):885.e1-885.e10
ObjectivesTo describe the normative values of sarcopenia among community-dwelling adults (≥21 years of age); compare the prevalence of sarcopenia using Asian Working Group for Sarcopenia criteria, 2014 (AWGS2014), Asian Working Group for Sarcopenia criteria, 2019 (AWGS2019), and European Working Group on Sarcopenia in Older People criteria, 2018 (EWGSOP2) guidelines; and identify factors associated with sarcopenia.DesignParticipants were recruited through random sampling. Sarcopenia assessments were performed using a dual-energy x-ray absorptiometry scan (muscle mass), handgrip test (muscle strength), and usual walking test (physical performance). Questionnaires were administered to evaluate lifestyle and cognition.Setting and ParticipantsIn total, 542 community-dwelling Singaporeans were recruited (21?90 years old, 57.9% women).MethodsWe assessed anthropometry, body composition, and questionnaire-based physical and cognitive factors, and estimated sarcopenia prevalence according to the AWGS2014, AWGS2019, and EWGSOP2 recommendations, and examined associations using logistic regression.ResultsAccording to AWGS2019, the Singapore population-adjusted sarcopenia prevalence was 13.6% (men 13.0%; women 14.2%) overall, and 32.2% (men 33.7%, women 30.9%) in those aged 60 years and above. The cut-offs derived from young adult reference group for low appendicular lean mass index were 5.28 kg/m2 for men and 3.69 kg/m2 for women (lower than AWGS recommended cut-off); for gait speed it was 0.82 m/s, (AWGS2019 recommended cut-off 1.0 m/s, AWGS2014 cut-off was 0.8 m/s); and for handgrip strength it was 27.9 kg/m2 for men and 16.7 kg/m2 for women (close to AWGS2019 recommendation). Age, sex, marital status, alcoholism, physical activity, body mass index, waist circumference, and global cognition were associated with sarcopenia (P < .05).Conclusions and ImplicationsThis is the first study to provide reference values of muscle mass, strength, and gait speed across the adult lifespan of Singaporeans. Using AWGS2019 criteria, sarcopenia is prominent in older age (32.2% in ≥60 years old), but it is already nontrivial (6.9%) among young and middle-age persons. Multidomain lifestyle modifications addressing muscle strength, cognition, and nutrition over the adult lifespan are important to delay the development of sarcopenia. 相似文献