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Malki A, Baltasar Badaya M, Dekker R, Verkerke GJ, Hijmans JM. Effects of individually optimized rocker midsoles and self-adjusting insoles on plantar pressure in persons with diabetes mellitus and loss of protective sensation. Diabetes Res Clin Pract 2024; 207:111077. [PMID: 38154536 DOI: 10.1016/j.diabres.2023.111077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/15/2023] [Accepted: 12/20/2023] [Indexed: 12/30/2023]
Abstract
INTRODUCTION Rocker shoes and insoles reduce peak pressure (PP) in persons with diabetes (DM) and loss of protective sensation (LOPS). However, they are handmade, leading to inconsistent effectiveness. If foot structure changes over time, high PP-locations also change. To address this, individualized algorithm based 3D-printed rockers and self-adjusting pressure-reducing insoles are applied. METHODS PP across seven foot regions was analyzed in 21 persons with DM and LOPS. Regions with PP < 200 kPa were considered not at risk (RnoR); regions with PP ≥ 200 kPa at risk (RaR). The aim was to offload RaR, while remaining PP < 200 kPa in RnoR. RESULTS Individualized rockers and self-adjusting insoles combined successfully reduce PP < 200 kPa (on average 24 % - 48 %) in all feet with toes, central and lateral forefoot identified as RaR. Same intervention reduces PP in 68 % of the feet with medial forefoot identified as RaR. With the heel as RaR, no intervention reduces PP successfully in all feet. CONCLUSIONS Individualized 3D-printed rockers combined with self-adjusting insoles reduce PP (< 200 kPa) in toes, central and lateral forefoot, but not in heels. Alternative insoles with medial arch support, heel cup and compliant midsole materials might enhance success rate across entire foot.
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Affiliation(s)
- A Malki
- University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands.
| | - M Baltasar Badaya
- University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands
| | - R Dekker
- University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands
| | - G J Verkerke
- University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands; University of Twente, Department of Biomechanical Engineering, Enschede, the Netherlands
| | - J M Hijmans
- University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands
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Chen R, Ruaengsri C, He H, Shudo Y, Neto D, Malki A, Bethencourt D, Theodore P, Woo J. Intracellular Cardiac Preservation Solution May Have Superior Clinical Outcomes to Extracellular Solution for Adult Heart Transplantation. J Heart Lung Transplant 2023. [DOI: 10.1016/j.healun.2023.02.1548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
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Ruaengsri C, Shudo Y, Malki A, Neto D, Chen R, Bethencourt D, Hiesinger W, MacArthur J, Currie M, Boyd J, Guenthart B, Lee A, Woo J. Successful Heart Transplantation Using a Portable Normothermic Ex-Vivo Donor Heart Preservation System for Extended Criteria Donor after Circulatory Death: A Case Series with Extended Perfusion Times. J Heart Lung Transplant 2023. [DOI: 10.1016/j.healun.2023.02.1295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
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Jamal A, Loukili M, Malki A, Rouf S, Latrech H. Le diabète de l’adolescent : quelles particularités ? Annales d'Endocrinologie 2021. [DOI: 10.1016/j.ando.2021.08.690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Liu X, Malki A, Cao Y, Li Y, Qian Y, Wang X, Chen X. Glucose- and Triglyceride-lowering Dietary Penta-O-galloyl-α-D-Glucose Reduces Expression of PPARγ and C/EBPα, Induces p21-Mediated G1 Phase Cell Cycle Arrest, and Inhibits Adipogenesis in 3T3-L1 Preadipocytes. Exp Clin Endocrinol Diabetes 2015; 123:308-16. [PMID: 25988880 DOI: 10.1055/s-0035-1548789] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Plant polyphenols, such as hydrolysable tannins, are present in the human diet and known to exhibit anti-diabetic and anti-obesity activity. We previously reported that the representative hydrolysable tannin compound α-penta-galloyl-glucose (α-PGG) is a small molecule insulin mimetic that, like insulin, binds to insulin receptor (IR) and activates the IR-Akt-GLUT4 signaling pathway to trigger glucose transport and reduce blood glucose levels in db/db and ob/ob diabetic mice. However, its effects on adipogenesis and lipid metabolism were not known. In this study, high fat diet (HFD)-induced diabetic and obese mice were treated with α-PGG to determine its effects on blood glucose and triglycerides. 3T3-L1 preadipocytes were used as a cell model for identifying the anti-adipogenic activity of α-PGG at molecular and cellular levels as a first step in elucidating the mechanism of action of the compound. In vivo, oral administration of α-PGG significantly reduced levels of blood glucose, triglyceride, and insulin in HFD-induced diabetic/obese mice (P<0.05). In vitro, α-PGG inhibited the differentiation of 3T3-L1 preadipocytes into mature adipocytes. α-PGG suppressed the expression of positive adipogenic factors PPARγ C/EBPα and mTOR and augmented the negative adipogenic factor Pref-1. Furthermore, α-PGG induced upregulation of p21 and G1 phase cell cycle arrest. In contrast, adipogenic signaling pathways mediated by insulin, the cAMP response element binding protein (CREB) and glucocorticoid receptor (GR), were not inhibited. RNAi knockdown of p21 led to a 4-fold increase in triglyceride level in 3T3-L1 preadipocytes treated with MDI and α-PGG compared to regular preadipocytes. These results indicate, for the first time, that α-PGG is blood triglyceride- and glucose-lowering in HFD-induced obese and diabetic mice. It selectively inhibited some but not all major adipogenic pathways as well as the mTOR-p21-mediated cell cycle regulatory pathway. It is very likely that these apparently diverse but coordinated activities together inhibited adipogenesis. These results expand our knowledge on how PGG works in adipocytes and further confirm that α-PGG functions as an orally-deliverable natural insulin mimetic with adipogenetic modulatory functions.
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Affiliation(s)
- X Liu
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
| | - A Malki
- Department of Health Sciences, Biomedical Science Program, College of Art and Sciences, Qatar University, Doha, Qatar
| | - Y Cao
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
| | - Y Li
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
| | - Y Qian
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
| | - X Wang
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
| | - X Chen
- Edison Biotechnology Institute, Ohio University, Athens, Ohio, USA
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Malki A, Mekhalif Z, Detriche S, Fonder G, Boumaza A, Djelloul A. Calcination products of gibbsite studied by X-ray diffraction, XPS and solid-state NMR. J SOLID STATE CHEM 2014. [DOI: 10.1016/j.jssc.2014.03.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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7
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Malki A, Bergmeier S. P0026 Novel quinuclidinone derivative induced apoptosis in human MCF-7 breast cancer cells by targeting p53. Eur J Cancer 2014. [DOI: 10.1016/j.ejca.2014.03.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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8
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Malki A, Fathy L, El Ashry ESH. Novel quinuclidinone derivatives induce apoptosis in lung cancer via sphingomyelinase pathways. Drug Res (Stuttg) 2013; 63:362-9. [PMID: 23585304 DOI: 10.1055/s-0033-1341463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We previously reported novel quinuclidinone analogs which induced apoptosis in lung and breast cancer cells. In this study, we designed and synthesized novel quinuclidinone analogs that showed cytotoxicity in lung cancer cells. The effects of these analogs were studied in H1299 human large cell lung carcinoma cells that are null for p53 and normal lung epithelial cell lines (NL-20). The effects of the analogs were investigated by MTT assay, ELISA based apoptotic assay, TUNEL assay, sphingomylinase activity, flow cytometry and western blot analysis. Our data indicated that derivatives 4 and 6 decreased cell proliferation and induced apoptosis in H1299 cells more than NL-20 cells. Derivatives 4 and 6 reduced percent of cells in G2/M phase in H1299 cells more than NL-20 cells and these results were confirmed by increased expression levels of cyclin E. Furthermore, derivatives 4 and 6 increased sphingomyelinase activity, caspase-8, and caspase-9 and JNK-1 expression level in H1299. Additionally, derivatives 4 and 6 induced Procaspase-3, PARP-1 cleavage, and increased caspase-3 activity. All these results confirm that our quinuclidinone derivatives provoke cytotoxicity in lung cancer cells through the interplay of key apoptosis molecules in different compartments of the cell beginning with an increase in sphingomyelinase activity.
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Affiliation(s)
- A Malki
- Biochemistry department, Faculty of Science, Alexandria University, Alexandria, Egypt.
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Malki A, Lavi N, Moinester M, Nassar H, Neeman E, Piasetzky E, Steiner V. Measurement of radon diffusion length in thin membranes. Radiat Prot Dosimetry 2012; 150:434-440. [PMID: 22232779 DOI: 10.1093/rpd/ncr421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Building regulations in Israel require the insulating of buildings against radon (222)Rn penetration from soil. In radon-prone areas membranes stretched between the soil and the building foundation are used, together with sealing other possible penetration routes. Designing the radon mitigation procedure requires checking that all sealing materials are practically, radon tight, having a thickness of at least three times the radon diffusion length. In this work, a very simple technique to evaluate the radon diffusion length in thin membranes, using a radon source of known activity and an activated charcoal canister as radon detector is presented. The theoretical formalism and measurement results for polyethylene membranes of different densities obtained in a recent comparison exercise are presented.
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Affiliation(s)
- A Malki
- School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv, Israel
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Rida SM, Youssef AM, Badr MH, Malki A, Sherif ZA, Sultan AS. Design, synthesis and evaluation of novel benzimidazoles, benzothiazoles and benzofurans incorporating pyrazole moiety as antiangiogenic agents. ACTA ACUST UNITED AC 2012; 62:63-74. [PMID: 22344550 DOI: 10.1055/s-0031-1295483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Novel benzimidazoles, benzothiazoles and benzofurans incorporating pyrazole moiety have been synthesized and screened for their antiangogenic activities, by testing their ability to inhibit human umbilical vein endothelial cell (HUVEC) proliferation, cord formation and migration in response to chemoattractant. 3 compounds 19, 23 and 26 showed antiangiogenic activities at non-cytotoxic concentrations. Compound 19 was the most active with chemotaxis activity data nearly comparable to that of the positive control, TNP-470. Compound 42 showed a significant cytotoxic effect on the tested cancer cell lines and less antiangiogenesis activity compared to compounds 19, 23 and 26. All the tested compounds, in contrary to TNP-470, interfered with the migratory function of HUVECs in response to vascular endothelial growth factor rather than the endothelial cells proliferation or cord formation. Moreover, a docked pose of compounds 19 and 26 was obtained bound to kinase insert domain receptor using Molecular Operating Environment module.
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Affiliation(s)
- S M Rida
- Department of Pharmaceutical Chemistry, Alexandria University, Alexandria, Egypt
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Tang A, Watson JW, Aclander J, Alster J, Asryan G, Averichev Y, Barton D, Baturin V, Bukhtoyarova N, Carroll A, Gushue S, Heppelmann S, Leksanov A, Makdisi Y, Malki A, Minina E, Navon I, Nicholson H, Ogawa A, Panebratsev Y, Piasetzky E, Schetkovsky A, Shimanskiy S, Zhalov D. n-p short-range correlations from (p,2p+n) measurements. Phys Rev Lett 2003; 90:042301. [PMID: 12570411 DOI: 10.1103/physrevlett.90.042301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2002] [Indexed: 05/24/2023]
Abstract
We studied the 12C(p,2p+n) reaction at beam momenta of 5.9, 8.0, and 9.0 GeV/c. For quasielastic (p,2p) events p(f), the momentum of the knocked-out proton before the reaction, was compared (event by event) with p(n), the coincident neutron momentum. For |p(n)|>k(F)=0.220 GeV/c (the Fermi momentum) a strong back-to-back directional correlation between p(f) and p(n) was observed, indicative of short-range n-p correlations. From p(n) and p(f) we constructed the distributions of c.m. and relative motion in the longitudinal direction for correlated pairs. We also determined that 49+/-13% of events with |p(f)|>k(F) had directionally correlated neutrons with |p(n)|>k(F).
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Affiliation(s)
- A Tang
- Department of Physics, Kent State University, Kent, Ohio 44242, USA
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12
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Leksanov A, Alster J, Asryan G, Averichev Y, Barton D, Baturin V, Bukhtoyarova N, Carroll A, Heppelmann S, Kawabata T, Makdisi Y, Malki A, Minina E, Navon I, Nicholson H, Ogawa A, Panebratsev Y, Piasetzky E, Schetkovsky A, Shimanskiy S, Tang A, Watson JW, Yoshida H, Zhalov D. Energy dependence of nuclear transparency in C (p,2p) scattering. Phys Rev Lett 2001; 87:212301. [PMID: 11736334 DOI: 10.1103/physrevlett.87.212301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2001] [Indexed: 05/23/2023]
Abstract
The transparency of carbon for (p,2p) quasielastic events was measured at beam momenta ranging from 5.9 to 14.5 GeV/c at 90 degrees c.m. The four-momentum transfer squared (Q2) ranged from 4.7 to 12.7 (GeV/c)(2). We present the observed beam momentum dependence of the ratio of the carbon to hydrogen cross sections. We also apply a model for the nuclear momentum distribution of carbon to obtain the nuclear transparency. We find a sharp rise in transparency as the beam momentum is increased to 9 GeV/c and a reduction to approximately the Glauber level at higher energies.
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Affiliation(s)
- A Leksanov
- Physics Department, Pennsylvania State University, University Park, Pennsylvania 16801, USA
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Malki A, Owunwanne A, Elgazzar A, Adbel-Dayem HM. Assessment of skeletal muscle damage in experimental animal using In-111 antimyosin. Int J Surg Investig 2001; 1:99-105. [PMID: 11341639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Skeletal muscle injury induced in the thigh muscles of New Zealand rabbits was investigated using radionuclide imaging technique after intravenous injection of In-111 antimyosin. Images were obtained for 3 weeks beginning from the first day of injury. The injury was visualized as early as 3 h after injection of the tracer. The mean uptake ratio of the injury to the normal muscle was 2.8 +/- 0.62 (p < 0.001) on the third to fifth day, decreasing with healing to 1.40 +/- 0.15 by the end of the study (3 weeks). The mean uptake ratio of the more severely crushed left to less severely crushed right side was 1.36 +/- 0.17 (p < 0.01) on the third day. The results of this study show that the radionuclide imaging technique using In-111 antimyosin is useful for the assessment of skeletal muscle damage and also for monitoring the progress of healing. This technique can be applied clinically to evaluate skeletal muscle damage in problematic fractures.
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Affiliation(s)
- A Malki
- Department of Surgery, Sulemaniya Medical Center, Bahrain
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Taghbalout A, Landoulsi A, Kern R, Yamazoe M, Hiraga S, Holland B, Kohiyama M, Malki A. Competition between the replication initiator DnaA and the sequestration factor SeqA for binding to the hemimethylated chromosomal origin of E. coli in vitro. Genes Cells 2000; 5:873-884. [PMID: 11122375 DOI: 10.1046/j.1365-2443.2000.00380.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Following replication initiation, the replication origin (oriC) in Escherichia coli enters a hemimethylated state at Dam methylation sites which are recognized by the SeqA protein. SeqA binds preferentially to hemimethylated GATC sequences of DNA in vitro. SeqA is essential for the synchronous initiation of chromosome replication from oriC copies in vivo. RESULTS We show that: (i) purified SeqA binds AT-rich and 13-mers regions and two DnaA boxes, R1 and M, of hemimethylated oriC. (ii) SeqA inhibits the in vitro replication of a hemimethylated oriC plasmid more efficiently than the fully methylated, (iii) SeqA inhibits competitive binding of DnaA protein to the regions of the hemimethylated oriC plasmid, explaining the mechanism of its inhibitory effect. The inhibition of DnaA binding by SeqA also occurs efficiently on a small hemimethylated oriC fragment containing both R1 and M DnaA boxes, but not the 13-mer region. CONCLUSIONS SeqA binds strongly the long region from the AT-rich region to the M DnaA box of the hemimethylated oriC DNA and releases DnaA molecules from the long region.
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Affiliation(s)
- A Taghbalout
- Institut Jacques Monod, CNRS, Université Paris 6-7, France
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Abstract
We describe a case of infected nonunion of the radius with extensive bone loss in an 11-year-old boy treated by centralization of the ulna. The technique used differs from the original Hey Groves procedure in that it preserves the distal end of the ulna with its important triangular fibrocartilage complex, thereby retaining stability and contour of the wrist joint. Our patient obtained a functionally and cosmetically satisfactory, stable forearm and wrist. We present the technique as a useful armament in the management of extensive bony defect of the radius arising from trauma or infection.
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Affiliation(s)
- A Malki
- The Department of Orthopaedic Surgery, Salmaniya Medical Center, P.O. Box 12, Bahrain, Arabian Gulf.
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Kohiyama M, Bahloul A, Kern R, Meury J, Reshetnyak E, Malki A, Guha S. Increased expression of a hemimethylated oriC binding protein, SeqA, in an aphA mutant. Biochimie 1998; 80:1043-6. [PMID: 9924983 DOI: 10.1016/s0300-9084(99)80010-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In Escherichia coli, the origin of DNA replication, oriC, becomes transiently hemimethylated at the GATC sequences immediately after initiation of replication and this hemimethylated state is prolonged because of its sequestration by a fraction of outer membrane. This sequestration is dependent on a hemimethylated oriC binding protein such as SeqA. We previously isolated a clone of phage lambda gt11 called hobH, producing a LacZ fusion protein which recognizes hemimethylated oriC DNA. Very recently, Thaller et al. (FEMS Microbiol. Lett. 146 (1997) 191-198) found that the same DNA segment encodes a non-specific acid phosphatase, and named the gene aphA. We show here that the interruption of the aphA reading frame by kanamycin resistance gene insertion, abolishes acid phosphatase (NAP) activity. Interestingly, in the membrane of the null mutant, the amount of SeqA protein is about six times higher than that in the parental strain, suggesting the existence of a regulatory mechanism between SeqA and NAP expression.
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Affiliation(s)
- M Kohiyama
- Biochimie Génétique, Institut Jacques-Monod, CNRS-Université Paris-VII, France
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Abstract
A seroprevalence study of canine leishmaniasis was carried out in five provinces in northern Morocco: Taounate, Al Hoceima, Zouagha Moulay Yacoub, Chefchaouen and Ouezzane. 55 localities have been concerned and a total of 1,013 dogs were screened, which represents almost 100% of the canine census. Of the screened dogs: 87 showed antibody titer > or = 100 when tested by IFAT (seroprevalence of 8.6%) and were distributed in 83 asymptomatics (without clinical symptoms) and four symptomatics (with one or several symptoms of leishmaniasis) with important variations according to the locality. Relative frequency of asymptomatic dogs was observed (8.2%), and the seroprevalence increased in middle altitude (500 m < altitude < 1,000 m) and high altitude (> or = 1,000 m). Parasites isolated from dogs were identified as L. infantum MON-1 by isoenzyme profile and Rsal digestion.
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Affiliation(s)
- R Nejjar
- Unité de Microbiologie, Institut Pasteur du Maroc, Casablanca, Maroc
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Gafsi R, Lecoy P, Malki A. Stress optical fiber sensor using light coupling between two laterally fused multimode optical fibers. Appl Opt 1998; 37:3417-3425. [PMID: 18273302 DOI: 10.1364/ao.37.003417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A stress optical fiber sensor was manufactured and tested. It uses light coupling between two parallel and laterally fused, all-silica multimode optical fibers along a cladding length of a few centimeters. This sensor is dedicated to the measurement of high values of stress. A theoretical model was developed using the mode coupling and the perturbation theory to calculate the global coupling coefficient of light. A serial optical fiber sensor network interrogated by the time-division multiplexing method was realized and tested. The major applications of this sensor are control and monitoring of civil engineering structures and concretes.
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Affiliation(s)
- J Wong-Chung
- Department of Orthopaedic Surgery, Salmaniya Medical Centre, Bahrain
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Malki A, Gafsi R, Michel L, Labarrνre M, Lecoy P. Impact and vibration detection in composite materials by using intermodal interference in multimode optical fibers. Appl Opt 1996; 35:5198-5201. [PMID: 21102957 DOI: 10.1364/ao.35.005198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An optical fiber sensor based on the intermodal interference principle is integrated in a composite material to detect impacts and vibrations. Six fibers are integrated at the top of a carbon/epoxy composite panel so as to form a grid into the structure. Spectral and temporal responses to impacts and acoustic vibrations of the sensor are compared with a piezoelectric accelerometer. The tests proved the facility of integration and the high sensitivity of the device. The location of impacts is performed with this arrangement by measuring the arrival times of the front waves to the fibers.
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21
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Malki A, Lecoy P, Marty J, Renouf C, Ferdinand P. Optical fiber accelerometer based on a silicon micromachined cantilever. Appl Opt 1995; 34:8014-8018. [PMID: 21068899 DOI: 10.1364/ao.34.008014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An intensity-modulated fiber-optic accelerometer based on backreflection effects has been manufactured and tested. It uses a multimode fiber placed at a spherical mirror center, and the beam intensity is modulated by a micromachined silicon cantilever. This device has applications as an accelerometer and vibrometer for rotating machines. It exhibits an amplitude linearity of ±1.2% in the range of 0.1-22 m s(-2), a frequency linearity of ±1% in the range of 0-100 Hz, and a temperature sensitivity of less than 0.03%/°C. The sensor is devoted to a wavelength-division multiplexing network.
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22
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Herrick J, Kern R, Guha S, Landoulsi A, Fayet O, Malki A, Kohiyama M. Parental strand recognition of the DNA replication origin by the outer membrane in Escherichia coli. EMBO J 1994; 13:4695-703. [PMID: 7925311 PMCID: PMC395404 DOI: 10.1002/j.1460-2075.1994.tb06793.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The outer membrane of Escherichia coli binds the origin of DNA replication (oriC) only when it is hemimethylated. We report here the results of a footprinting analysis with the outer membrane which demonstrate that its interaction with oriC occurs mainly at the left moiety of the minimal oriC, where 10 out of 11 Dam methylation sites are concentrated. Two regions, flanking the Integration Host Factor (IHF) sites, are preferentially recognized at the minimum membrane concentration at which oriC plasmid replication is inhibited in vitro. We have identified the putative proteins involved in hemimethylated oriC binding and cloned one of the corresponding genes (hobH). The purified LacZ-HobH fusion protein specifically binds oriC DNA at the same preferential sites as the membrane. A mutant of the hobH gene reveals partial asynchronous initiation of DNA replication.
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Affiliation(s)
- J Herrick
- Institut Jacques Monod, CNRS, Université Paris 7, France
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Giraldo-Suárez R, Fernández-Tresguerres E, Díaz-Orejas R, Malki A, Kohiyama M. The heat-shock DnaK protein is required for plasmid R1 replication and it is dispensable for plasmid ColE1 replication. Nucleic Acids Res 1993; 21:5495-9. [PMID: 8265367 PMCID: PMC310592 DOI: 10.1093/nar/21.23.5495] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Plasmid R1 replication in vitro is inactive in extracts prepared from a dnaK756 strain but is restored to normal levels upon addition of purified DnaK protein. Replication of R1 in extracts of a dnaKwt strain can be specifically inhibited with polyclonal antibodies against DnaK. RepA-dependent replication of R1 in dnaK756 extracts supplemented with DnaKwt protein at maximum concentration is partially inhibited by rifampicin and it is severely inhibited at sub-optimal concentrations of DnaK protein. The copy number of a run-away R1 vector is reduced in a dnaK756 background at 30 degrees C and at 42 degrees C the amplification of the run-away R1 vector is prevented. However a runaway R1 vector containing dnaK gene allows the amplification of the plasmid at high temperature. These data indicate that DnaK is required for both in vitro and in vivo replication of plasmid R1 and show a partial compensation for the low level of DnaK by RNA polymerase. In contrast ColE1 replication is not affected by DnaK as indicated by the fact that ColE1 replicates with the same efficiency in extracts from dnaKwt and dnaK756 strains.
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24
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Rastegar B, Wagner P, Bozin M, Coffin JP, Fintz P, Guillaume G, Jundt F, Krishan K, Rami F, Malki A, Zahar M. In-plane particle-residue correlations in the 40Ar(1100 MeV)+24Mg reaction. Phys Rev C Nucl Phys 1992; 46:366-369. [PMID: 9968118 DOI: 10.1103/physrevc.46.366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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25
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Friedman L, Abel LA, Jesberger JA, Malki A, Meltzer HY. Saccadic intrusions into smooth pursuit in patients with schizophrenia or affective disorder and normal controls. Biol Psychiatry 1992; 31:1110-8. [PMID: 1525275 DOI: 10.1016/0006-3223(92)90155-s] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two types of saccadic intrusions into smooth pursuit eye tracking, anticipatory saccades (AS), and square wave jerks (SWJ), were measured in 23 patients with schizophrenia, 16 patients with affective disorder, and 21 normal controls. Constant velocity (5 degrees and 20 degrees/sec) predictable targets were employed. High resolution infrared oculography was employed to record eye movements. Although most subjects had at least one SWJ, there were no significant group differences, and the highest individual rates of SWJ were seen in the normal control group. On the other hand, AS were never seen in normals, but were present in 25%-44% of patients with either schizophrenia or affective disorder. Both patient groups had significantly more AS than controls, but the two patient groups were not significantly different.
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Affiliation(s)
- L Friedman
- Laboratory of Biological Psychiatry, Case Western Reserve University, University Hospitals of Cleveland, OH 44106
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26
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Malki A, Kern R, Kohiyama M, Hughes P. Inhibition of DNA synthesis at the hemimethylated pBR322 origin of replication by a cell membrane fraction. Nucleic Acids Res 1992; 20:105-9. [PMID: 1738587 PMCID: PMC310332 DOI: 10.1093/nar/20.1.105] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The replication of both ColE1-type plasmids and plasmids bearing the origin of replication of the Escherichia coli chromosome (oriC) has been shown to be inhibited by hemimethylation of adenine residues within GATC sequences. In the case of oriC plasmids, this inhibition was previously shown to be mediated by the specific affinity of the hemimethylated origin DNA for an outer cell membrane fraction. Here, we suggest that a similar mechanism is operating in the case of the ColE1-like plasmid pBR322 as (i) a hemimethylated DNA fragment carrying the promoter for the RNA which primes DNA synthesis (RNAII) is specifically bound by the same membrane fraction and, (ii) the addition of the membrane fraction to a soluble assay of pBR322 replication results in preferential inhibition of initiation on the hemimethylated template. We suggest that membrane sequestration of hemimethylated origin DNA and/or associated replication genes following replication may be a common element restricting DNA replication to precise moments in the cell cycle.
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Affiliation(s)
- A Malki
- Department of Molecular Biology, Institut Jacques Monod, Universite Paris VII, France
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27
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Abstract
The smooth pursuit responses to 5 degrees and 20 degrees/sec constant-velocity stimuli were recorded from 23 patients with schizophrenia, 16 affective disorder patients, and 21 normals using low-noise infrared oculography. Pursuit gain, catch-up saccade (CUS) rate and amplitude, and their interrelationships were examined. Gain in the schizophrenic patients was reduced only at 20 degrees/sec, but for both patient groups, CUS rate at 5 degrees/sec was significantly lower than in normals. Using CUS rate at 20 degrees/sec, the patient groups could be distinguished from each other (the rate for schizophrenic patients being highest, and the rate for affectives the lowest) but neither differed significantly from normals. The diagnostic groups did not differ significantly in mean CUS amplitude, although there was a trend for patients to have larger saccades. Gain-CUS rate correlation was strong in normals but reduced or absent in both patient groups. These results indicate that the ocular motor systems of patients with schizophrenia and affective disorders process eye position error abnormally.
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Affiliation(s)
- L A Abel
- Department of Ophthalmology, Indiana University, Indianapolis 46202-5175
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28
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Malki A, Hughes P, Kohiyama M. In vitro roles of Escherichia coli DnaJ and DnaK heat shock proteins in the replication of oriC plasmids. Mol Gen Genet 1991; 225:420-6. [PMID: 2017137 DOI: 10.1007/bf00261682] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Heat shock proteins have been shown to be involved in many cellular processes in procaryotic and eucaryotic cells. Using an in vitro DNA replication assay, we show that DNA synthesis initiated at the chromosomal origin of replication of Escherichia coli (oriC) is considerably reduced in enzyme extracts isolated from cells bearing mutations in the dnaK and dnaJ genes, which code for heat shock proteins. Furthermore, unlike DNA synthesis in wild-type extracts, residual DNA synthesis in dnaK and dnaJ extracts is thermosensitive. Although thermosensitivity can be complemented by the addition of DnaK and DnaJ proteins, restoration of near wild-type replication levels requires supplementary quantities of purified DnaA protein. This key DNA synthesis initiator protein is shown to be adsorbed to DnaK affinity columns. These results suggest that at least one of the heat shock proteins. DnaK, exerts an effect on the initiation of DNA synthesis at the level of DnaA protein activity. However, our observation of normal oriC plasmid transformation ratios and concentrations in heat shock mutants at permissive temperatures would suggest that heat shock proteins play a role in DNA replication mainly at high temperatures or under other stressful growth conditions.
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Affiliation(s)
- A Malki
- Institute Jacques Monod, Centre National de la Recherche Scientifique, Université Paris, France
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29
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Landoulsi A, Malki A, Kern R, Kohiyama M, Hughes P. The E. coli cell surface specifically prevents the initiation of DNA replication at oriC on hemimethylated DNA templates. Cell 1990; 63:1053-60. [PMID: 2257623 DOI: 10.1016/0092-8674(90)90508-c] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A particular outer membrane fraction previously defined as possessing specific affinity for the hemimethylated form of the origin of replication of the E. coli chromosome (oriC) is shown to inhibit the initiation of DNA synthesis at this site on hemimethylated DNA templates in vitro. The replication of fully methylated or unmethylated DNA templates is not affected. Also, no inhibition is observed if initiation takes place at random sites on the hemimethylated template. The key inactivation step appears to be membrane inhibition of DnaA initiator protein binding to oriC. Remethylation of the membrane-bound hemimethylated DNA results in reactivation. Our results demonstrate direct involvement of the membrane in the control of DNA replication. We propose that association/dissociation of the origin from the cell membrane is one of the control elements governing interinitiation times in E. coli.
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Affiliation(s)
- A Landoulsi
- Institut Jacques Monod, Université Paris VII, France
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30
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Gonin M, Coffin JP, Guillaume G, Jundt F, Wagner P, Fintz P, Heusch B, Malki A, Fahli A, Kox S, Merchez F, Mistretta J. Preequilibrium emission and incomplete fusion of low and medium mass heavy ion systems. Phys Rev C Nucl Phys 1988; 38:135-145. [PMID: 9954787 DOI: 10.1103/physrevc.38.135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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31
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Miller DR, Malki A. Large saccular aneurysm and A-V fistula of the brachial vessels. J Cardiovasc Surg (Torino) 1985; 26:605-7. [PMID: 4066747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This paper reports a 39-year-old patient who developed an unusually large saccular false aneurysm and A-V fistula of the brachial vessels following a neglected penetrating wound. Rapid enlargement to 15 cm appeared after one year and the aneurysm was then stable for the six months prior to operative repair. The aneurysm was excised and lateral closure of the vessels restored continuity with uneventful recovery.
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Abstract
The present study was performed primarily in order to determine whether gastric mucosa of rats with portal hypertension has different functional and histologic features when compared with controls, and second to quantitate and compare morphologic and functional changes after exposure to topical ethanol. Portal hypertension was produced by staged portal venous occlusion, and in these animals portal pressure was 32 +/- 2 cm saline compared with 18 +/- 2 cm in sham-operated controls (p less than 0.005). Before ethanol, portal hypertensive rats compared with controls had significantly higher luminal pH (2.9 +/- 0.3 vs. 1.9 +/- 0.1), increased H+ back-diffusion (loss of 138 +/- 10 vs. 57 +/- 16 microEq H+/h), lower potential difference (8 +/- 1 mV lower than controls), and extensive submucosal edema (submucosal thickness 325 +/- 25 vs. 138 +/- 18 micrometers). After 3 h of exposure to 2 ml intragastric absolute ethanol, the area of macroscopic hemorrhagic mucosal injury was significantly greater in portal hypertensive rats than in controls (34.0 +/- 8.7% vs. 7.6 +/- 2.1%), confirmed histologically by the greater number of deep hemorrhagic necrotic lesions and extent of mucosal length involved. Furthermore, after ethanol, portal hypertensive rats compared with controls had significantly increased gastric volume (14.4 +/- 1.5 vs. 8.3 +/- 0.6 ml), Na+ (86.6 +/- 8.0 vs. 64.6 +/- 8.0 mEq/L), pH (7.1 +/- 0.3 vs. 4.3 +/- 0.4), H+ back-diffusion (loss of 309 +/- 41 vs. 207 +/- 33 microEq H+/h), and protein and blood loss (100% increases over controls). These results indicate that gastric mucosa of portal hypertensive rats has distinctive functional and histologic abnormalities that can explain its increased susceptibility to erosive injury after ethanol. This study quantitatively confirms in an animal model the clinical observations that portal hypertension may predispose to severe gastric mucosal injury.
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33
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Miller RL, Sarfeh IJ, Sanderfer T, Malki A, Tidwell R, Mason GR. Acute portal hypertension and reduced renal blood flow: an intestinal-renal neurogenic reflex. J Surg Res 1983; 34:319-24. [PMID: 6834815 DOI: 10.1016/0022-4804(83)90078-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In a series of experiments in anesthetized dogs, the origin and mechanism of reduced renal blood flow (RBF) during acute portal hypertension was investigated. With acute superior mesenteric vein (SMV) occlusion and normalization of cardiac hemodynamics RBF remained reduced at 66 +/- 14 ml/min compared to baseline of 160 +/- 25 ml/min (P less than 0.01). Neither acute superior mesenteric artery occlusion, nor acute hepatic portal hypoperfusion with normal SMV pressures maintained by SMV-caval shunt, resulted in reduction of RBF. Cross-perfusion studies failed to produce alterations of RBF in recipient dogs from donor dogs with SMV occlusion, reduced RBF, and normal cardiac outputs. Finally, splanchnic ganglionectomy prevented RBF reduction during SMV occlusion after volume restoration. We conclude that reduced RBF during acute portal hypertension is a result of an intestinal-renal neurogenic reflex initiated by intestinal venous congestion.
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