Precipitation Hardening and Corrosion Behavior of Friction Stir Welded A6005-TiB2 Nanocomposite

N. Abu‑warda,M. D. López,B. González,E. Otero,M. D. Escalera‑Rodríguez,S. Cruz,P. Rey 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

Precipitation hardening and corrosion behavior of a friction stir welding (FSW) based on the aluminum alloy A6005 reinforcedwith TiB2nanoparticles have been studied. Mechanical alloying (MA) and hot extrusion techniques have beenemployed as processing route followed by FSW. Samples characterization has been performed by DSC and TEM, and precipitationstrengthening of the bulk samples and the FSW joint has been evaluated by micro-hardness tests after T6 thermaltreatment. TEM characterization revealed the presence of Mg–Si hardening phases, mainly of β′ phase, and dispersoids ofα-Al(FeMnCr)Si into the aluminum matrix. The results revealed that samples subjected to MA had less susceptibility toT6 thermal treatment and that the presence of nano-TiB2 reinforcement accelerates aging time. In addition, electrochemicaltests based on polarization tests have been performed in 3.5% NaCl solution to assess the effect of FSW process on corrosionbehavior. The FSW joint had worse corrosion behavior since the passive Al2O3film was not generated on the weldzone. SEM–EDS analysis revealed that pits nucleated mainly in sites with a higher presence of Fe contaminant which actscathodically with respect to the aluminum matrix, producing galvanic corrosion.

Ectopic Intrathoracic Kidney due to Diaphragmatic Eventration Detected on Bone Scan

Warda Ahmad 대한핵의학회 2024 핵의학 분자영상 Vol.58 No.2

The technetium-99m methylene diphosphonate (99mTc-MDP) whole-body bone scan along with single-photon emissioncomputed tomography (SPECT/CT) can detect challenging soft tissue uptake patterns. We present a case of a 67-year-oldfemale in whom the 99mTc-MDP scan, performed 3 hours after injection, revealed abnormal soft tissue uptake in the rightthoracic region. No functioning right kidney was seen in the right lumbar region. Hybrid SPECT/CT revealed an ectopicright kidney in the subdiaphragmatic location, accompanied by gut loops and eventration of the right-sided diaphragm. Thiscase underscores the value of SPECT/CT in identifying and characterizing unexpected anatomical abnormalities, such asectopic kidneys.

Simulated hyperglycemia in rat cardiomyocytes: A proteomics approach for improved analysis of cellular alterations

Warda, Mohamad,Kim, Hyoung Kyu,Kim, Nari,Youm, Jae Boum,Kang, Sung Hyun,Park, Won Sun,Khoa, Tran Min,Kim, Young Hwan,Han, Jin WILEY-VCH Verlag 2007 Proteomics Vol.7 No.15

<P>Diabetic hyperglycemia can lead to stress-related cellular apoptosis of cardiac tissue. However, the mechanism by which hyperglycemia inflicts this damage on the structure and function of the heart is unclear. In this study, we examined the relationship between proteome alterations, mitochondrial function, and major biochemical and electrophysiological changes affecting cardiac performance during simulated short-term hyperglycemia. Two-dimensional comparative proteomics analysis of rat hearts perfused with glucose at high (30 mM) or control (5.5 mM) levels revealed that glucose loading alters cardiomyocyte proteomes. It increased expression levels of initial enzymes of the tricarboxylic acid cycle, and of enzymes of fatty acid β-oxidation, with consequent up-regulation of enzymes of mitochondrial electron transport. It also markedly decreased expression of enzymes of glycolysis and the final steps of the tricarboxylic acid cycle. Glucose loading increased the rate of Bax-independent apoptosis. High glucose increased the duration of the action potential and elevated level of intracellular cytoplasmic calcium. Surprisingly, glucose loading did not influence levels of nitric oxide or mitochondrial superoxide in isolated cardiomyocytes. In summary, short-term simulated hyperglycemia attenuated expression of many anti-apoptotic proteins. This effect was apparently mediated via alterations in multiple biochemical pathways that collectively increased apoptotic susceptibility.</P>

A matter of life, death and diseases: mitochondria from a proteomic perspective.

Warda, Mohamad,Kim, Hyoung Kyu,Kim, Nari,Ko, Kyung Soo,Rhee, Byoung Doo,Han, Jin Future Drugs Ltd 2013 Expert review of proteomics Vol.10 No.1

<P>Mitochondria are highly ordered, integrated organelles that energize cellular activities and contribute to programmed death by initiating disciplined apoptotic cascades. This review seeks to clarify our understanding of mitochondrial structural-functional integrity beyond the resolved nuclear genome by unraveling the dynamic mitochondrial proteome and elucidating proteome/genome interplay. The roles of mechanochemical coupling between mitoskeleton and cytoskeleton and crosstalk with other organelles in orchestrating cellular outcomes are explained. The authors also review the modulation of mitochondrial-related oxidative stress on apoptosis and cancer development and the context is applied to interpret pathogenetic events in neurodegenerative disorders and cardiovascular diseases. The accumulated proteomics evidence is used to describe the integral role that mitochondria play and how they influence other intracellular organelles. Possible mitochondrial-targeted therapeutic interventions are also discussed.</P>

e-러닝을 위한 손 제스처 어플리케이션

와르다익람 ( Warda Ikram ),정윤지 ( Yoonji Jeong ),이병권 ( Byeonggwon Lee ),엄기현 ( Kyhyun Um ),조경은 ( Kyungeun Cho ) 한국정보처리학회 2015 한국정보처리학회 학술대회논문집 Vol.22 No.1

본 논문에서는 e-러닝 시스템 및 직관적인 제스처를 제안한다. e-러닝 시스템은 휴대가 쉽고 비용효율성이 높은 모션센서를 사용하며, 학생이 사용하기 쉽게 직관적인 제스처와 간단한 인터페이스 구성에 초점을 맞추었다. 시스템 속 시각적 효과와 재미있는 그래픽은 학생들의 관심을 끌어 학습에 흥미를 높여주고 학습 능력을 향상시킬 수 있다.

Screening for Del 185 AG and 4627C>A BRCA1 Mutations in Breast Cancer Patients from Lahore, Pakistan

Aziz, Faiza,Fatima, Warda,Mahmood, Saqib,Khokher, Samina Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.4

Breast cancer contributes to approximately 23% of the cancer cases identified and 14% of cancer related deaths worldwide. Including a strong association between genetic and environmental factors, breast cancer is a complex and multi factorial disorder. Two high penetration breast cancer susceptibility genes (BRCA1 and BRCA2) have been identified, and germ line mutations in these are thought to account for between 5% and 10% of all breast cancer cases. The human BRCA1 gene, located on 17q, is involved in the regulation of cell proliferation by aiding in DNA repair, transcriptional responses to DNA damage and cell cycle check points. Mutations in this gene enhance cell proliferation and facilitate formation of tumors. Two mutations, the 185 deletion of AG and the 4627 substitution from C to A, are founder mutations in the BRCA1 gene for breast cancer in Asian populations. Allele specific PCR was performed to detect these selected mutations in 120 samples. No mutation of 4627 C to A was detected in the samples and only one of the patients had the 185 del AG mutation in the heterozygous condition. Our collected samples had lower consanguinity and family history indicating the greater involvement of environmental as compared to genetic factors.

Reduced Fertility and Fecundity among Patients with Bipolar I Disorder and Schizophrenia in Egypt

Hader Mansour,Kareem Kandil,Warda Fathi,Mai Elassy,Ibtihal Ibrahim,Hala Salah,Amal Yassin,Hanan Elsayed,Salwa Tobar,Hala El-Boraie,Ahmed Eissa,Mohamed Elhadidy,Nahed E. Ibrahim,Wafaa El-Bahaei,Vishwaj 대한신경정신의학회 2011 PSYCHIATRY INVESTIGATION Vol.8 No.3

Objective To evaluate reproduction among patients with bipolar I disorder (BP1) or schizophrenia (SZ) in Egypt. Methods BP1 patients (n=113) were compared with community based, demographically balanced controls (n=124) and SZ patients (n=79, DSM-IV). All participants were evaluated using structured interviews and corroborative data were obtained from relatives. Standard indices of procreation were included in multivariate analyses that incorporated key demographic variables. Results Control individuals were significantly more likely to have children than BP1 or SZ patients (controls 46.8%, BP1 15.9%, SZ 17.7%), but the BP1-SZ differences were non-significant. The average number of children for BP1 patients (0.37±0.9) and SZ patients (0.38±0.9) was significantly lower than for controls (1.04±1.48) (BP1 vs controls, p<0.001; SZ vs controls, p<0.001). The frequency of marriages among BP1 patients was nominally higher than the SZ group, but was significantly lower than controls (BP1: 31.9% SZ: 27.8% control: 57.3%). Even among married individuals, BP1 (but not SZ) patients were childless more often than controls (p=0.001). The marital fertility, i.e., the average number of children among patients with conjugal relationships for controls (1.8±1.57) was significantly higher than BP1 patients (1.14±1.31, p=0.02), but not significantly different from SZ patients (1.36±1.32, p=0.2). Conclusion Selected reproductive measures are significantly and substantially reduced among Egyptian BP1 patients. The reproductive indices are similar among BP1 and SZ patients, suggesting a role for general illness related variables. Regardless of the cause/s, the impairment constitutes important, under-investigated disability. Objective To evaluate reproduction among patients with bipolar I disorder (BP1) or schizophrenia (SZ) in Egypt. Methods BP1 patients (n=113) were compared with community based, demographically balanced controls (n=124) and SZ patients (n=79, DSM-IV). All participants were evaluated using structured interviews and corroborative data were obtained from relatives. Standard indices of procreation were included in multivariate analyses that incorporated key demographic variables. Results Control individuals were significantly more likely to have children than BP1 or SZ patients (controls 46.8%, BP1 15.9%, SZ 17.7%), but the BP1-SZ differences were non-significant. The average number of children for BP1 patients (0.37±0.9) and SZ patients (0.38±0.9) was significantly lower than for controls (1.04±1.48) (BP1 vs controls, p<0.001; SZ vs controls, p<0.001). The frequency of marriages among BP1 patients was nominally higher than the SZ group, but was significantly lower than controls (BP1: 31.9% SZ: 27.8% control: 57.3%). Even among married individuals, BP1 (but not SZ) patients were childless more often than controls (p=0.001). The marital fertility, i.e., the average number of children among patients with conjugal relationships for controls (1.8±1.57) was significantly higher than BP1 patients (1.14±1.31, p=0.02), but not significantly different from SZ patients (1.36±1.32, p=0.2). Conclusion Selected reproductive measures are significantly and substantially reduced among Egyptian BP1 patients. The reproductive indices are similar among BP1 and SZ patients, suggesting a role for general illness related variables. Regardless of the cause/s, the impairment constitutes important, under-investigated disability.

Changes of Cytosolic Ca2+ under Metabolic Inhibition in Isolated Rat Ventricular Myocytes

강성현,김나리,주현,염재범,박원선,Mohamed Warda,김형규,Dang Van Cuong,김태호,김의용,한진 대한약리학회 2005 The Korean Journal of Physiology & Pharmacology Vol.9 No.5

To characterize cytosolic Ca2+ fluctuations under metabolic inhibition, rat ventricular myocytes were exposed to 200μM 2,4-dinitrophenol (DNP), and mitochondrial Ca2+, mitochondrial membrane potential (ΔΨm), and cytosolic Ca2+ were measured, using Rhod-2 AM, TMRE, and Fluo-4 AM fluorescent dyes, respectively, by Laser Scanning Confocal Microscopy (LSCM). Furthermore, the role of sarcolemmal Na+/Ca2+ exchange (NCX) in cytosolic Ca2+ efflux was studied in KB-R7943 and Na+-free normal Tyrode's solution (143 mM LiCl ). When DNP was applied to cells loaded with Fluo-4 AM, Fluo-4 AM fluorescence intensity initially increased by 70±10% within 70±10 s, and later by 400±200% at 850±46 s. Fluorescence intensity of both Rhod-2 AM and TMRE were initially decreased by DNP, coincident with the initial increase of Fluo-4 AM fluorescence intensity. When sarcoplasmic reticulum (SR) Ca2+ was depleted by 1μM thapsigargin plus 10μM ryanodine, the initial increase of Fluo-4 AM fluorescence intensity was unaffected, however, the subsequent progressive increase was abolished. KB-R7943 delayed both the first and the second phases of cytosolic Ca2+ overload, while Na+-free solution accelerated the second. The above results suggest that: 1) the initial rise in cytosolic Ca2+ under DNP results from mitochondrial depolarization; 2) the secondary increase is caused by progressive Ca2+ release from SR; 3) NCX plays an important role in transient cytosolic Ca2+ shifts under metabolic inhibition with DNP.

Differential Activation of Ras/Raf/MAPK Pathway between Heart and Cerebral Artery in Isoproterenol-induced Cardiac Hypertrophy

김현주,김나리,주현,염재범,박원선,Mohamed Warda,강성현,Vu Thi Thu,Tran Minh Khoa,한진 대한약리학회 2005 The Korean Journal of Physiology & Pharmacology Vol.9 No.5

Cardiac hypertrophy contributes an increased risk to major cerebrovascular events. However, the molecular mechanisms underlying cerebrovascular dysfunction during cardiac hypertrophy have not yet been characterized. In the present study, we examined the molecular mechanism of isoproterenol (ISO)-evoked activation of Ras/Raf/MAPK pathways as well as PKA activity in cerebral artery of rabbits, and we also studied whether the activations of these signaling pathways were altered in cerebral artery, during ISO-induced cardiac hypertrophy compared to heart itself. The results show that the mRNA level of c-fos (not c-jun and c-myc) in heart and these genes in cerebral artery were considerably increased during cardiac hypertrophy. These results that the PKA activity and activations of Ras/Raf/ERK cascade as well as c-fos expression in rabbit heart during cardiac hypertrophy were consistent with previous reports. Interestingly, however, we also showed a novel finding that the decreased PKA activity might have differential effects on Ras and Raf expression in cerebral artery during cardiac hypertrophy. In conclusion, there are differences in molecular mechanisms between heart and cerebral artery during cardiac hypertrophy when stimulated with β2 adrenoreceptor (AR), suggesting a possible mechanism underlying cerebrovascular dysfunction during cardiac hypertrophy.

Toward a better understanding of preeclampsia: Comparative proteomic analysis of preeclamptic placentas

Kim, Young Nam,Kim, Hyoung Kyu,Warda, Mohamad,Kim, Nari,Park, Won Sun,Prince, Ab del Bary,Jeong, Dae Hoon,Lee, Dae Shim,Kim, Ki Tae,Han, Jin Wiley (John WileySons) 2007 Proteomics. Clinical applications Vol.1 No.12

<P>Preeclampsia (PE), a pregnancy-specific syndrome of hypertension, proteinuria, and other systemic disturbances, is a state of widespread endothelial dysfunction secondary to defective placentation. Morphologically, the current data displayed degenerative and apoptotic changes in the mitochondria and villous trophoblasts of preeclamptic placenta. To reveal the superimposing alterations in placental proteins that might explain the pathophysiology of PE, we performed 2-DE MALDI-TOF MS/MS proteomics analysis of differentially expressed placental proteins with placenta from eight normal and eight preeclamptic pregnancies. The identified proteins were confirmed by Western blot analysis. We also performed morphologic evaluation of preeclamptic placentas under both electron and light microscopy. The results disclosed the marked overexpression of chaperonin 60, GST, VDAC, ERp29, and cathepsin D in PE. These proteomics findings clearly suggest the possible cellular battle against mitochondria-originated oxidative stress during PE that either end up with recovery or apoptosis. These results provide a better understanding of proteomic alterations and may help in clarification of stress-related changes in preeclamptic placentas.</P>