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Dipeptidyl peptidase-4 expression in pancreatic tissue from patients with congenital hyperinsulinism
Sofia A Rahman Senthil Senniappan Maha Sherif Sophia Tahir Khalid Hussain 《International journal of clinical and experimental pathology》2015,8(7):8199-8208
Congenital hyperinsulinism (CHI) is caused by unregulated insulin release and leads to hyperinsulinaemic-hypoglycaemia (HH). Glucagon like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), peptide YY (PYY) and the enzyme; dipeptidyl peptidase-4 (DPP-4) all regulate appetite and glucose homeostasis. These proteins have been identified as possible contributors to HH but the mechanism remains poorly understood. We aimed to look at the expression pattern of pancreatic DPP-4 in children with focal and diffuse CHI (FCHI and DCHI, respectively). Using immunohistochemistry; we determined DPP-4 expression patterns in the pancreas of CHI patients. DPP-4 was found to be expressed in the pancreatic β, α and δ-cells in and around the focal area. However, it was predominantly co-localised with β-cells in the paediatric tissue samples. Additionally, proliferating β-cells expressed DPP-4 in DCHI, which was absent in the FCHI pancreas. Insulin was found to be present in the exocrine acini and duct cells of the DCHI pancreas suggestive of exocrine to endocrine transdifferentiation. Furthermore, 6 medically-unresponsive DCHI pancreatic samples showed an up-regulation of total pancreatic DPP-4 expression. In conclusion; the expression studies have shown DPP-4 to be altered in HH, however, further work is required to understand the underlying role for this enzyme. 相似文献
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Ahmed S. Bahaj Haddad H. Alkaff Bashair N. Melebari Anwar N. Melebari Suhail I. Sayed Syeddah S. Mujtaba Sherif K. Abdelmonim Saeed A. Alghamdi Fares E. Alghamdi Omar A. Abu Suliman Mohammad A. Alessa Firas R. Abi Sheffah Anas H. Al-Tammas Rajab A. Al-Zahrani Osama A. Marglani John C. Heaphy Osama A. Bawazir Ameen Z. Alherabi 《Saudi medical journal》2020,41(10):1098
Objectives:To evaluate the accuracy and efficacy of fine-needle aspiration cytology (FNAC) in diagnosing thyroid nodules, correlating it with the histopathological findings.Methods:A retrospective evaluation of 314 patients was undertaken at a tertiary referral center of King Abdullah Medical City (KAMC), Makkah, Kingdom of Saudi Arabia, between 2010-2019. Patients who presented with thyroid swellings underwent ultrasonography and FNAC. If indicated, surgery was performed. The FNAC findings were compared to the final histopathological reports.Results:The findings for FNAC from our data set of 314 patients showed a sensitivity value of 79.8%, specificity of 82.1%, accuracy of 74.8%, positive predictive value of 74.8%, and negative predictive value of 85.9%.Conclusion:Our study showed that FNAC has high sensitivity and specificity in the initial evaluation of patients with thyroid nodules. When guided by ultrasonography, the accuracy can be markedly improved. Molecular markers once widely available can improve the diagnostic power of FNAC to be no less than the histopathologic evaluation of thyroid tissue. 相似文献
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Ekemini D. Akpan Ibanga O. Isaac Lukman O. Olasunkanmi Eno E. Ebenso El-Sayed M. Sherif 《RSC advances》2019,9(51):29590
Electrochemical, surface morphology, density functional theory and Monte Carlo simulation methods were employed in investigating the effects of (2E,2′E)-2,2′-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2H,5H,9H,10H)-diylidene)bis(N-phenylhydrazinecarbothioamide) (IAB-NP), (2E,2′E)-2,2′-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2H,5H,9H,10H)-diylidene)bis(N-(2,4-difluorophenyl)hydrazinecarbothioamide)IAB-ND) and (2E,2′E)-2,2′-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2H,5H,9H,10H)-diylidene)bis(N-(2-fluorophenyl) hydrazinecarbothioamide) (IAB-NF) on mild steel corrosion in 1 M HCl solution. From the studies, compounds IAB-NP, IAB-ND and IAB-NF inhibit mild steel corrosion in the acid and the protection efficiencies were found to increase with the increase in concentration of each compound. At the optimum inhibitor concentration of 1.5 × 10−4 M, the inhibition efficiencies (%) of the compounds are in the order IAB-NF (90.48) > IAB-ND (87.48) > IAB-NP (85.28). Potentiodynamic polarization measurements revealed that all the compounds acted as mixed-type corrosion inhibitors. Experimental data for the adsorption of the studied molecules on a mild steel surface in 1 M HCl fitted into the Langmuir adsorption isotherm and the standard free energies of adsorption (ΔGoads) suggested both physisorption and chemisorption mechanisms. Scanning electron microscopy analyses confirmed the formation of a protective film on the mild steel surface by the inhibitor molecules, resulting in protection of the metal from corrosive electrolyte ions. The experimental findings were corroborated by both theoretical density functional theory and Monte Carlo simulation studies.Three novel acridine-based thiosemicarbazones were investigated for their corrosion inhibition potentials on mild steel in 1 M HCl using combined electrochemical, DFT and Monte Carlo simulation techniques. 相似文献
66.
Jameela Abdulaziz Kari Majed Alzahrany Basem El-Deek Muhanad Maimani Sherif El-Desoky 《Indian journal of pediatrics》2014,81(10):1020-1026
Objectives
To evaluate the social consequences of dialysis on children and their parents.Methods
From January through June 2012 short structured interviews with parents or caregivers of children on peritoneal dialysis (PD) or hemodialysis (HD) who were followed up at King Abdulaziz University Hospital, King Faisal Specialty Hospital and Research Center, or the Kidney Center at King Fahad Hospital were conducted. Data were analyzed using the Statistical Package for the Social Sciences.Results
Thirty six children (22 boys and 16 girls) and their families were included. The mean (SD) age of the children was 11.5?±?6.87 y, and the mean (SD) duration of dialysis was 28?±?11.32 mo. Only one third of the families had the opportunity to choose the modality of dialysis. Both modalities of dialysis had a negative effect on fathers’ jobs in over 50 % of the cases. Similarly, both modalities of treatment had a considerable impact on the quality of care provided by the mothers to other family members. There was no difference between the two modalities on the frequency of admissions.Conclusions
Both PD and HD had a negative impact on fathers’ jobs and on the level of care provided by mothers to the rest of the family. 相似文献67.
Sherif Shalaby Gautham Chitragari Brandon J. Sumpio Bauer E. Sumpio 《The International journal of angiology》2014,23(3):187-192
Extracellular signal-regulated kinase 5 (ERK5) has been reported to regulate endothelial cell integrity and protect from vascular dysfunction under continuous laminar flow. However, the effect of flow on ERK5 levels has not been determined. Confluent human umbilical vein endothelial cells (HUVECs) were seeded on fibronectin coated glass slides and serum starved for 2 hours with 1% fetal bovine serum (FBS). HUVECs were then exposed to to and fro flow (TFF), pulsatile forward flow (PFF), or continuous laminar flow (CLF) in a parallel plate flow chamber for up to 2 hours. At the end of experiment, cell lysates were prepared and immunoblotted with antibodies to total ERK5. Both CLF and TFF exhibited a decrease in ERK5 after levels after 2-hour exposure. However, the level of ERK5 for PFF remained the same. Disturbed, but not uniform pulsatile, flow decreases ERK5 levels in HUVECs. 相似文献
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Alyasiri NS Mehdi SJ Alam MS Ali A Mandal AK Gupta S Singh I Rizvi MM 《Journal of cancer research and clinical oncology》2012,138(1):103-109