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Muneer MS, Mohamed AS, Vizcaino MA, Raghunathan A, Naidich TP, Vibhute PG. Chordoid glioma: a rare old foe but a new pathological and radiological presentation. Clin Imaging 2021; 78:160-164. [PMID: 33836423 DOI: 10.1016/j.clinimag.2021.03.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/11/2021] [Accepted: 03/05/2021] [Indexed: 11/25/2022]
Abstract
Chordoid glioma (CG) is a rare WHO Grade II neoplasm of the anterior third ventricle. We report two cases of CG with new presentation in terms of histopathology and location: a case of CG with osseous metaplasia evident on imaging, and another CG, unusually located in the posterior portion of the third ventricle.
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Saad AM, El‐Saadony MT, Mohamed AS, Ahmed AI, Sitohy MZ. Impact of cucumber pomace fortification on the nutritional, sensorial and technological quality of soft wheat flour‐based noodles. Int J Food Sci Technol 2021. [DOI: 10.1111/ijfs.14970] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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El-Saadony MT, Elsadek MF, Mohamed AS, Taha AE, Ahmed BM, Saad AM. Effects of Chemical and Natural Additives on Cucumber Juice's Quality, Shelf Life, and Safety. Foods 2020; 9:E639. [PMID: 32429212 PMCID: PMC7281498 DOI: 10.3390/foods9050639] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 12/21/2022] Open
Abstract
Microbial contamination affects beverages' lifetime, quality, and safety. Cucumber crops are seasonally spoiled because of the overproduction. The current study aimed to maximize the importance of natural preservatives and reduce the usage of artificial ones to prolong the cucumber juice's storage life, enhance flavor, and control the microorganisms after protein isolate and organic acids supplementation. The additions included control (no addition), citric, benzoic acid, sodium salts, kidney bean pepsin hydrolysate (KPH), chicken egg protein isolate (CEPI), duck egg protein isolate (DEPI), and quail egg protein isolate (QEPI) as J-Control, J-Citric, J-Benzoic, J-sod. Citrate, J-sod. Benzoate, J-KPH, J-CEPI, J-DEPI, and J-QEPI, respectively. The antioxidant activity of these additives and juices was evaluated by DPPH radical scavenging activity. The antimicrobial activity, including antibacterial and antifungal activities, was evaluated by using disc assay and the radial growth of fungal mycelium, respectively. The phenolic compounds and flavonoids were estimated by a spectrophotometer as Gallic acid equivalent (GAE) and quercetin equivalent (QE), respectively. Moreover, chemical parameters such as pH, total soluble solids (TSS), Titratable acidity (TTA), and Vitamin C were evaluated by AOAC. Finally, the color properties were estimated by a spectrophotometer, using the Hunter method. KPH had higher significant (p ≤ 0.05) antioxidant activity (88%), along with antimicrobial activity. It significantly (p ≤ 0.05) reduced the growth of G+ and G- bacteria by 71%-97% and 58%-66% respectively. Furthermore, it significantly (p ≤ 0.05) inhibited the tested fungi growth by 70%-88% and the other additives less than that. During the storage of cucumber juice for an interval of zero, two, four, and six months, the phenolic compounds and flavonoids were significantly (p ≤ 0.05) decreased. Consequently, the potential activity of the juice was reduced; in addition, pH and vitamin C were significantly (p ≤ 0.05) decreased during the storage period. Meanwhile, the TSS and Titratable acidity were significantly raised. As for color and sensory properties, J-sod. Benzoate, J-KPH, J-CEPI, and J-DEPI had significantly (p ≤ 0.05) high scores in color, taste, and flavor against the control. Generally, the usage of natural additives extends the cucumber juice's lifetime and increased the manufacture of high-quality and valuable juice.
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Hanafi NI, Mohamed AS, Md Noor J, Abdu N, Hasani H, Siran R, Osman NJ, Ab Rahim S, Sheikh Abdul Kadir SH. Ursodeoxycholic acid upregulates ERK and Akt in the protection of cardiomyocytes against CoCl2. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr8150. [PMID: 27323195 DOI: 10.4238/gmr.15028150] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ursodeoxycholic acid (UDCA) is used to treat liver diseases and demonstrates cardioprotective effects. Accumulation of the plasma membrane sphingolipid sphingomyelin in the heart can lead to atherosclerosis and coronary artery disease. Sphingomyelinases (SMases) break down sphingomyelin, producing ceramide, and inhibition of SMases activity can promote cell survival. We hypothesized that UDCA regulates activation of ERK and Akt survival signaling pathways and SMases in protecting cardiac cells against hypoxia. Neonatal cardiomyocytes were isolated from 0- to 2-day-old Sprague Dawley rats, and given 100 μM CoCl2, 150 μM H2O2, or placed in a hypoxia chamber for 24 h. The ameliorative effects of 100-μM UDCA treatment for 12 h were then assessed using MTS, QuantiGene Plex (for Smpd1 and Smpd2), and SMase assays, beating rate assessment, and western blotting (for ERK and Akt). Data were analyzed by the paired Student t-tests and one-way analyses of variance. Cell viability decreased significantly after H2O2 (85%), CoCl2 (50%), and hypoxia chamber (52%) treatments compared to the untreated control (100%). UDCA significantly counteracted the effects of chamber- and CoCl2- induced hypoxia on viability and beating rate. However, no significant differences were observed in acid SMase gene and protein expression between the untreated, CoCl2, and UDCA-CoCl2 groups. In contrast, neutral SMase gene and protein expression did significantly differ between the latter two groups. ERK and Akt phosphorylation was higher in hypoxic cardiomyocytes treated with UDCA than those given CoCl2 alone. In conclusion, UDCA regulates the activation of survival signaling proteins and SMases in neonatal rat cardiomyocytes during hypoxia.
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Mikhail MW, Metwally AM, Allam KAM, Mohamed AS. Rodents as reservoir host of intestinal helminthes in different Egyptian agroecosystems. JOURNAL OF THE EGYPTIAN SOCIETY OF PARASITOLOGY 2009; 39:633-640. [PMID: 19795770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Hymenolepis diminuta were detected in rodents in all zones surveyed Governorates under studied (Suez, Menoufia, Giza, Damietta and Beni-Sewaf). The highest infestation recorded at Suez and Demiatta Governorates. On the other hand, rodents at Menoufia and Beni-Sewaf showed there is no convincing evidence that they infested with H. diminuta. The existence of one species of nematode namely, Streptopharagus kuntzi were recorded at Suez, Giza and Demiatta Governorates only. While Menoufia and Beni-Sewaf Governorates showed no convincing evidence that, they infested with nematode. Worms were recovered from Norway rats. Data indicated that Rattus norvegicus were the most vulnerable species at infection with H. diminuta and Streptopharagus kuntzi. Summer is highly infested with nematode in comparison with other seasonal study.
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Al-Motabagani MA, Mohamed AS. Congenital malformations in mice induced by addiction to alcohol and cocaine. EAST AFRICAN MEDICAL JOURNAL 2005; 82:433-8. [PMID: 16261922 DOI: 10.4314/eamj.v82i8.9330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To study the teratogenic effect of either alcohol alone, cocaine alone, or a combination of both alcohol and cocaine on mice foetuses. DESIGN Eighty pregnant mice were divided into four equal groups. In the first (alcohol) group, the pregnant females were given absolute ethanol at 2.5 gm/100 gm twice daily by oro-gastric incubation. In the second (cocaine) group, the pregnant females received cocaine hydrochloride at 20 mg/ 100 gm daily by intraperitoneal injection. In the third (combined) group, the pregnant females received alcohol at 2.5 gm/100 gm twice daily and cocaine hydrochloride at 20 mg/100 gm daily. In all groups the treatment started from the 6th day to the 15th day of gestation. The fourth group is the control. SETTINGS Department of Anatomy, College of Medicine, King Faisal University, Dammam, Saudi Arabia and Department of Anatomy, College of Medicine, Al-Azhar University, Cairo, Egypt. INTERVENTION The pregnant mice were sacrificed at the 20th day of gestation (one day before term). The uterine contents were evaluated and the number of dead and live foetuses was determined as well as the number of resorption. The living foetuses were examined for soft tissue anomalies. SUBJECTS Eighty pregnant mice. RESULTS This study revealed a significant increase in the number of dead foetuses and foetal growth parameters showed a significant decrease in the combined group. This group showed significant increase in anomalies of the head as hydrocephaly and complete cleft palate, of the kidney as bilateral secondary hydronephrosis and ectopic kidney, of the limbs, and of the tail as kinked tail. Both alcohol and cocaine groups alone showed significant increase in some of the anomalies of the head while in the alcohol group there was unilateral hydronephrosis. CONCLUSION This study indicates that the combined administration of alcohol and cocaine has a more teratogenic effect than either alcohol or cocaine alone.
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Mohamed AS, Thomson J, McDonald KJ, Hillyard DZ, Mark PB, Elliott HL, Jardine AG. Circulating Endothelial Cells in Renal Transplant Recipients. Transplant Proc 2005; 37:2387-90. [PMID: 15964423 DOI: 10.1016/j.transproceed.2005.03.126] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2005] [Indexed: 11/17/2022]
Abstract
Circulating endothelial cells (CECs) are a marker of endothelial injury and endothelial dysfunction. We measured CECs in 95 patients with functioning renal transplants at risk of premature cardiovascular (CV) disease and in normal control subjects. We were unable to demonstrate consistent relationships between CEC levels and conventional CV risk factors in transplant recipients. However, CEC levels were increased in patients with a history of rejection. We conclude that CECs are of little use as a marker of CV risk in this population but may be a useful marker to monitor allograft rejection.
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Mohamed AS, Rivas-Plata KA, Kraas JR, Saleh SM, Swope SL. Src-class kinases act within the agrin/MuSK pathway to regulate acetylcholine receptor phosphorylation, cytoskeletal anchoring, and clustering. J Neurosci 2001; 21:3806-18. [PMID: 11356869 PMCID: PMC6762727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023] Open
Abstract
Synaptogenesis at the neuromuscular junction requires agrin-induced stable localization of acetylcholine receptors (AChRs) at the endplate. The effects of agrin are transduced by the muscle-specific receptor tyrosine kinase (MuSK). This study provides evidence that Src-class protein tyrosine kinases mediate the effects of agrin-activated MuSK to regulate clustering and anchoring of AChRs in skeletal muscle. MuSK was complexed with both Src and Fyn in the C2 mouse muscle cell line. These associations were enhanced by agrin and by increasing protein tyrosine phosphorylation with pervanadate. Coupling between MuSK and the Src-class kinases in vivo appeared to be caused by a phosphotyrosine-SH2 domain interaction because binding of MuSK to the SH2 domains of Fyn and Src in vitro was specific, enhanced by phosphorylation, and dependent on MuSK autophosphorylation. In addition, Src and Fyn phosphorylated MuSK. AChR phosphorylation, stimulated by agrin or pervanadate, was inhibited by blocking Src-class kinases with PP1. Furthermore, agrin-induced clustering and cytoskeletal anchoring of AChRs was dependent on Src-family kinases. These data support the conclusion that Fyn and Src act downstream of MuSK to regulate the stable localization of AChRs at the neuromuscular endplate during agrin-induced synaptogenesis.
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Piketty C, Weiss L, Thomas F, Mohamed AS, Belec L, Kazatchkine MD. Long-term clinical outcome of human immunodeficiency virus-infected patients with discordant immunologic and virologic responses to a protease inhibitor-containing regimen. J Infect Dis 2001; 183:1328-35. [PMID: 11294663 DOI: 10.1086/319861] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2000] [Revised: 01/30/2001] [Indexed: 11/03/2022] Open
Abstract
Within a prospective cohort of 150 human immunodeficiency virus (HIV)-infected patients who began first-line protease inhibitor therapy in 1996, the outcome of 42 patients with discrepant virologic and immunologic responses to antiretroviral treatment at 12 months was analyzed at 30 months of treatment. The incidence of AIDS-defining events and deaths (14%) in the group of patients with immunologic responses in the absence of a virologic response was higher than that in full-responder patients (2%); yet, the incidence in this group was lower than that in patients with no immunologic response, despite a virologic response (21%), and was lower than that in patients without an immunologic or virologic response (67%; P<.0001, log-rank test). Differences in outcome were significant (relative risk, 6.9; 95% confidence interval, 1.9-39.3) when factors for progression were compared with those of responder patients. The results support the relevance of the CD4 cell marker over plasma HIV load for predicting clinical outcome in patients who do not achieve full immunologic and virologic responses.
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Miermont AM, Mohamed AS, Swope SL. Generation of phosphorylation state-specific SRC-class kinase antibodies for analysis of kinase activation. J Immunol Methods 2000; 246:203-15. [PMID: 11121560 DOI: 10.1016/s0022-1759(00)00292-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Protein phosphorylation is a major molecular mechanism by which cellular function is regulated. In order to accomplish rapid and specific biochemical changes via phosphorylation, the activity of a protein kinase must be dynamically regulated. Historically, the activity of each protein kinase has been analyzed using a unique in vitro biochemical assay with a specific substrate and detection procedure. These assays require the use of radioactivity and are often labor intensive. Upon activation, most protein kinases autophosphorylate. Thus, a technical approach to detect changes in kinase activity is to measure autophosphorylation. The purpose of this protocol is to provide a detailed stepwise procedure for measuring the regulation of Src-class kinase activity using phosphorylation state-specific antibodies. Antibodies to a phosphorylated peptide derived from the autophosphorylation site of Src-family kinases are developed and affinity purified. The purified antibodies are used to analyze the regulation of Src and Fyn activity in a mouse muscle cell line. It is anticipated that the utility of these phosphorylation state-specific antibodies will ultimately result in the development of similar antibodies useful for analyzing the activity of many different kinases.
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Addous A, Mohamed AS, Ismail G, Al-Hashemy A. Post-Transplant Diabetes Mellitus in Kidney Transplant Recipients with Special Reference to Association with HLA Antigens. SAUDI JOURNAL OF KIDNEY DISEASES AND TRANSPLANTATION 2000; 11:559-562. [PMID: 18209345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
One hundred fifty three kidney transplant recipients whose grafts functioned for longer than one year were evaluated for evidence of post-transplant diabetes mellitus (PTDM). Twenty-six patients (17%) developed PTDM. Patients with PTDM were older than controls (mean age 49.4 vs 37.9 years). There was no demonstrable association between sex of patients and PTDM. The body mass index (BMI) was persistently higher in patients with PTDM compared to controls, although the difference did not amount to statistical significance. The association of PTDM with HLA-A28, A30 and B8 observed in other studies was not seen in our patients. Similarly, neither the positive association of HLA-DR3 and DR4, nor the negative association of HLA-B7 and DR2 seen in population-based studies of insulin dependent diabetes mellitus, were seen in our patients with PTDM. To our knowledge, this is the first report that has looked into the association of HLA antigens and PTDM in Saudi Arabia.
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Gendeh BS, Murad S, Razi AM, Abdullah N, Mohamed AS, Kadir KA. Skin prick test reactivity to foods in adult Malaysians with rhinitis. Otolaryngol Head Neck Surg 2000; 122:758-62. [PMID: 10793361 DOI: 10.1016/s0194-5998(00)70211-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of the study was to determine the incidence of food and house dust mite (HDM) allergy in patients with nasal congestion and rhinorrhea attending the Otorhinolaryngology Clinic, National University of Malaysia, Kuala Lumpur. This was a prospective matched, controlled study of patients skin prick tested with commercial food and common aeroallergens. The participants were 148 Malaysian adults with symptoms of nasal congestion and rhinorrhea and 113 adult Malaysian control subjects without rhinitis symptoms. The skin prick test (SPT) was used to evaluate 11 foods common to the Malaysian diet and 3 HDM inhalants. Forty-eight percent of the patients with rhinitis had positive SPT results to foods, compared with 4.4% of control subjects (P < 0.05). The most commonly implicated foods were shrimp (48%) and rice (30%), which are common in the Malaysian diet. Seventy-two percent of rhinitis patients had positive SPT results to HDM, compared with 22.2% of control subjects (P < 0.05). Patients with rhinitis also had significantly more gastrointestinal problems than control subjects (P < 0.05). The incidences of HDM and food allergy are significantly greater in Malaysian adults with rhinitis symptoms than in control subjects without rhinitis. The effect of avoidance or immunotherapy awaits further study.
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Osman MY, Sharaf IA, Mohamed AS, Osman HM. Effect of the carbamate "aldicarb" on acetyl cholinesterase extracted from whole and different parts of rat brain (in vitro and in vivo studies). J Egypt Public Health Assoc 2000; 75:301-21. [PMID: 17216925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Aldicarb, a synthetic carbamate compound used as an insecticide and herbicide, is also employed as a pharmacological cholinergic agent in therapeutic forms. Inhibition of the enzyme AChE, which results in accumulation of ACh, is the basis for its use as an insecticide and it resulted in toxicity in a variety of animals including man. In this work, experiments were carried out in vitro and in vivo to study the effects of aldicarb on the activity of ChE enzyme extracted from whole and five different parts of rat brain, namely: basal ganglia, frontal cortex, medulla oblongata, pons and cerebellum. Kinetic measurements of Michaelis constants (Km), enzyme inhibitor dissociation constants (Ki) as well as the rate of carbamylation (k2c) and binding constants (Kl) for the inhibition of the enzyme obtained from the different parts were done. The carbamylation rate (degree of inhibition of AChE by carbamate) and binding constant for inhibition of whole and different parts of brain in vitro, indicated that the carbamylation rate constants of pons, medulla oblongata and cerebellum were higher than those of other parts. Inhibition of AChE in the different parts of the brain in vitro by aldicarb was of the competitive type, with different enzyme inhibitor dissociation constants (Ki). In vivo studies showed that the inhibition was marked in the enzyme obtained from pons, medulla oblongata and cerebellum; the parts responsible for vital centers and balance which coinsize with the in vitro results.
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Kuo YH, Fabiani JN, Mohamed AS, Couetil JP, Lévy M, Gutmann L, Carpentier AF, Bélec L. Decreasing occupational risk related to blood-borne viruses in cardiovascular surgery in Paris, France. Ann Thorac Surg 1999; 68:2267-72. [PMID: 10617015 DOI: 10.1016/s0003-4975(99)01051-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Surgeons face the risk of patient-to-physician transmission of blood-borne viruses. This risk is related to the seroprevalence of the viruses in the patient population. METHODS The seroprevalence of the human immunodeficiency virus, hepatitis B virus, and hepatitis C virus were determined in cardiovascular patients at Hôpital Broussais in Paris, France, over a 5-year period (1994 to 1998). RESULTS Hepatitis C virus is the most prevalent virus in the patient population, whereas human immunodeficiency virus is the least frequent. The seroprevalence of hepatitis C virus and human immunodeficiency virus has decreased over time, whereas hepatitis B virus has remained constant. We apply the seroprevalence data to a mathematical model to estimate the occupational risk of seroconversion faced by surgeons over the length of their career. Our results show that the principal risk faced by the surgeon arises from hepatitis B virus and hepatitis C virus. The decreasing seroprevalence of the hepatitis C virus has resulted in a decrease in the occupational risk. CONCLUSIONS The probability of becoming infected with a blood-borne virus over the career of the surgeon is notable. The greatest occupational risk to the surgeon is from the hepatitis viruses and not HIV.
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Mohamed AS, Khan BA. A more positive diagnosis of irritable bowel syndrome in Saudi patients. Ann Saudi Med 1999; 19:459-61. [PMID: 17277521 DOI: 10.5144/0256-4947.1999.459] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Iacono RP, Carlson JD, Mohamed AS, Kuniyoshi SM. Reversal of levodopa failure syndrome by posteroventral-ansa pallidotomy. ADVANCES IN NEUROLOGY 1999; 80:619-22. [PMID: 10410779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Mohamed AS, Swope SL. Phosphorylation and cytoskeletal anchoring of the acetylcholine receptor by Src class protein-tyrosine kinases. Activation by rapsyn. J Biol Chem 1999; 274:20529-39. [PMID: 10400682 DOI: 10.1074/jbc.274.29.20529] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Src class protein-tyrosine kinases bind to and phosphorylate the nicotinic acetylcholine receptor of skeletal muscle. This study provided evidence for the functional importance of Src kinases in regulating the nicotinic acetylcholine receptor at the neuromuscular junction. Three Src class kinases, Fyn, Fyk, and Src, each formed a complex with the endplate-specific cytoskeletal protein rapsyn. In addition, cellular phosphorylation by each kinase was stimulated by rapsyn in heterologous transfected cells. Several lines of evidence supported rapsyn as a substrate for Src kinases. Most importantly, rapsyn regulation of Fyn, Fyk, and Src resulted in phosphorylation of the nicotinic acetylcholine receptor beta and delta subunits and anchoring of the receptor to the cytoskeleton. Both nicotinic acetylcholine receptor phosphorylation and cytoskeletal anchoring were blocked by the Src kinase-selective inhibitor herbimycin A. Rapsyn alone also induced a modest increase in nicotinic acetylcholine receptor phosphorylation and cytoskeletal translocation. However, inhibition by herbimycin A and a catalytically inactive dominant negative Src demonstrated that the effects of rapsyn were mediated by endogenous Src kinases. These data support the importance of Src class kinases for stabilization of the nicotinic acetylcholine receptor at the endplate during synaptic differentiation at the neuromuscular junction.
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Bélec L, Mohamed AS, Authier FJ, Hallouin MC, Soe AM, Cotigny S, Gaulard P, Gherardi RK. Human herpesvirus 8 infection in patients with POEMS syndrome-associated multicentric Castleman's disease. Blood 1999; 93:3643-53. [PMID: 10339470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
The polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes (POEMS) syndrome is a rare multisystemic disorder associated with osteosclerotic myeloma and multicentric Castleman's disease (MCD). Human herpesvirus type 8 (HHV-8) DNA sequences have been detected in lymph nodes of about 40% of human immunodeficiency virus (HIV)-negative patients with MCD, and in bone marrow stromal cells of patients with multiple myeloma. Considering these data, we investigated the presence of HHV-8 in 18 patients with POEMS syndrome (9 with MCD), by nested polymerase chain reaction (N-PCR) to detect DNA sequenses in various cells and tissues obtained by biopsy or at autopsy (13 patients, of whom 7 had MCD), and by an immunofluorescence assay to detect anti-HHV-8 IgG antibodies in blood (18 patients, of whom 9 had MCD). Detection of HHV-8 DNA was performed using three different N-PCR, targeting nonoverlapping regions in open reading frame (ORF) 25 and ORF26. Seven of 13 (54%) POEMS patients had HHV-8 DNA sequences in their tissues, as assessed by all three N-PCR, and 9 of 18 (50%) had circulating anti-HHV-8 antibodies. HHV-8 was mainly detected in the subset of POEMS patients with MCD (6 of 7 [85%] for DNA sequences; 7 of 9 [78%] for antibodies). The percentage of positive N-PCR was higher in lymph nodes than in bone marrow samples (P <.02). Sequencing of amplicons showed a homogeneous restricted variability in the ORF26 region, characteristic of the minority subgroup B defined by Zong, and responsible for isoleucine and glycine substitutions at amino acid positions 134 and 167. These findings strongly suggest an association of HHV-8 infection with POEMS syndrome-associated MCD.
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Addous AO, Greening KA, Sjolander UA, Mohamed AS, Al Hashemy A. Nocardia asteroides in renal transplant recipients. Saudi Med J 1999; 20:319-322. [PMID: 27614493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
Full text is available as a scanned copy of the original print version.
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Mukari SZ, Vandort S, Ahmad K, Saim L, Mohamed AS. Parents' awareness and knowledge of the special needs of their hearing-impaired child. THE MEDICAL JOURNAL OF MALAYSIA 1999; 54:87-95. [PMID: 10972010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
We surveyed parents of school-aged hearing impaired children to investigate their awareness and knowledge of the special needs of their child, especially in the area of the usage of hearing aids and methods of communication. Questionnaires were distributed to parents of hearing impaired children at 13 special schools for the deaf in Malaysia. Out of 1,267 questionnaires given out, 787 (62.1%) were completed and returned. Results of the survey indicated the majority of parents (68.6%) suspected hearing loss late, that is after their child's first birthday, and there was a significant time lag before the suspicion was confirmed. Over 82.8% of the children were diagnosed only after 1 year of age, with 41.3% being diagnosed after 3 years of age. Hearing aids were fitted late (mean = 5.32 years; SD = 2.66). Hearing aid ownership was influenced by the factors of socio-economic level and ethnic group (p < 0.01) whereas knowledge of use and proper care of the aids was influenced by socio-economic level (p < 0.01). Communication methods were generally inappropriate with 41.3% of the mothers and 48.5% of the fathers reporting ignorance of Bahasa Malaysia Kod Tangan, the sign language that is commonly used by their children. The parents' choice of communication method was not significantly influenced by socio-economic level or ethnic group. The study revealed the present inadequate state of services available for the rehabilitation of children with congenital hearing impairment.
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Bélec L, Authier FJ, Mohamed AS, Soubrier M, Gherardi RK. Antibodies to human herpesvirus 8 in POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes) syndrome with multicentric Castleman's disease. Clin Infect Dis 1999; 28:678-9. [PMID: 10194095 DOI: 10.1086/515169] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Mohamed AS, Dignam JD, Schlender KK. Cardiac myosin-binding protein C (MyBP-C): identification of protein kinase A and protein kinase C phosphorylation sites. Arch Biochem Biophys 1998; 358:313-9. [PMID: 9784245 DOI: 10.1006/abbi.1998.0857] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Myosin binding protein C (MyBP-C) is a major myofibril-associated protein in cardiac muscle which is subject to reversible phosphorylation. Cardiac MyBP-C is a substrate in vivo and in vitro for cAMP-dependent protein kinase (PKA) and calcium/phospholipid-dependent protein kinase (PKC). Chicken cardiac MyBP-C was phosphorylated by PKA to 3.0 mol phosphate/mol and by PKC to 2.0 mol phosphate/mol. Tryptic phosphopeptides from MyBP-C were purified by successive iron iminodiacetate column chromatography and reversed-phase high-performance liquid chromatography. Three phosphopeptides purified from PKA-phosphorylated MyBP-C contained phosphoserine [T1, (RTS[P]LAGGGR) and T2, (KRDS[P]FLR)] or phosphothreonine (CT3, MT[P]SAFL). PKC phosphorylated two of the same sites (T1 and T2) as PKA and an additional site [T2a (TGTTYKPPS[P]YK)]. PKA phosphorylation sites corresponding to peptides T1, T2, and T3 were identified in the N-terminus of the cDNA deduced amino acid sequence (S265, S300, and T274, respectively). The PKC-specific site in peptide T2a was at position S1169. cDNA clones encoding rat cardiac MyBP-C were isolated, and the segment corresponding to PKA and major PKC phosphorylation sites was sequenced. Chicken cardiac MyBP-C has a threonine at position 274 (CT3), whereas rat cardiac MyBP-C has a serine at the corresponding position. Only chicken cardiac MyBP-C had a phosphorylatable residue at the position corresponding to S1169. All of the cardiac MyBP-C phosphorylation sites are absent in known sequences of skeletal muscle MyBP-C isoforms.
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Bélec L, Mohamed AS, Lechapt-Zalcman E, Authier FJ, Lange F, Gherardi RK. Lack of HHV-8 DNA sequences in sarcoid tissues of French patients. Chest 1998; 114:948-9. [PMID: 9743199 DOI: 10.1378/chest.114.3.948] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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49
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Bélec L, Authier J, Eliezer-Vanerot MC, Piédouillet C, Mohamed AS, Gherardi RK. Myoglobin as a polymerase chain reaction (PCR) inhibitor: a limitation for PCR from skeletal muscle tissue avoided by the use of Thermus thermophilus polymerase. Muscle Nerve 1998; 21:1064-7. [PMID: 9655125 DOI: 10.1002/(sici)1097-4598(199808)21:8<1064::aid-mus11>3.0.co;2-u] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Skeletal muscle tissue contains polymerase chain reaction (PCR) inhibitors that are coextracted by conventional nucleic acid extraction procedures. Myoglobin, a heme-containing molecule, was shown to act as a potent Thermus aquaticus DNA polymerase inhibitor and is likely to be involved in muscle tissue-associated PCR inhibition. The use of Thermus thermophilus DNA polymerase avoids muscle tissue-associated PCR inhibition, and should be used in case of small amounts or instability of the targeted nucleic acid.
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Bélec L, Tevi-Benissan C, Mohamed AS, Carbonel N, Matta M, Grésenguet G. Enhanced detection of human herpesvirus-8 and cytomegalovirus in semen of HIV-seropositive asymptomatic heterosexual men living in Central Africa. AIDS 1998; 12:674-6. [PMID: 9583611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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