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Golshani S, Vatanara A, Balalaie S, Kadkhoda Z, Abdollahi M, Amin M. Development of a Novel Histatin-5 Mucoadhesive Gel for the Treatment of Oral Mucositis: In Vitro Characterization and In Vivo Evaluation. AAPS PharmSciTech 2023; 24:177. [PMID: 37639072 DOI: 10.1208/s12249-023-02632-6] [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] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 08/03/2023] [Indexed: 08/29/2023] Open
Abstract
Antimicrobial peptides have appeared to be promising candidates for therapeutic purposes due to their broad antimicrobial activity and non-toxicity. Histatin-5 (Hst-5) is a notable salivary antimicrobial peptide that exhibited therapeutic properties in the oral cavity. Oral mucositis is an acute inflammation of the oral cavity, following cancer therapy. The current treatment methods of oral mucositis have low effectiveness. The aim of this study was to design, formulate and characterize a mucoadhesive gel delivery system for Hst-5 usage in the treatment of oral mucositis. Carbopol 934 and hydroxypropyl methylcellulose (HPMC) have been used in the development of a Hst-5 mucoadhesive gel that was optimized by using Box-Behnken design. The optimized formulation was evaluated in-vitro, based on mucoadhesive strength, viscoelasticity, spreadability, release rate, peptide secondary structure analysis, antimicrobial activity, and storage stability. The efficacy of Hst-5 gel was assessed in vivo in a chemotherapy-induced mucositis model. The results showed a sustained release of Hst-5 from the new formulation. Hst-5 gel exerted antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The histopathological, immunohistochemical and statistical analysis showed that the Hst-5 gel had wound healing activity in vivo. The findings of this study indicate that the mentioned compound possesses promising potential as a novel and efficient therapeutic agent in managing oral mucositis. Moreover, the results suggest that the compound is commercially feasible for further development and utilization.
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Affiliation(s)
- Shiva Golshani
- Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, 16th Azar Street, Tehran, Iran
| | - Alireza Vatanara
- Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Saeed Balalaie
- Peptide Chemistry Research Center, K. N. Toosi University of Technology, P. O. Box 15875-4416, Tehran, Iran
| | - Zeinab Kadkhoda
- Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Abdollahi
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Amin
- Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, 16th Azar Street, Tehran, Iran.
- Pharmaceutical Quality Assurance Research Center, the Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran.
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Saeedi M, Hariri R, Iraji A, Ahmadi A, Mojtabavi S, Golshani S, Faramarzi MA, Akbarzadeh T. Novel N'-substituted benzylidene benzohydrazides linked to 1,2,3-triazoles: potent α-glucosidase inhibitors. Sci Rep 2023; 13:8960. [PMID: 37268722 DOI: 10.1038/s41598-023-36046-y] [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] [Received: 07/23/2022] [Accepted: 05/28/2023] [Indexed: 06/04/2023] Open
Abstract
Herein, various N'-substituted benzylidene benzohydrazide-1,2,3-triazoles were designed, synthesized, and screened for their inhibitory activity toward α-glucosidase. The structure of derivatives was confirmed using 1H- and 13C-NMR, FTIR, Mass spectrometry, and elemental analysis. All derivatives exhibited good inhibition with IC50 values in the range of 0.01 to 648.90 µM, compared with acarbose as the positive control (IC50 = 752.10 µM). Among them, compounds 7a and 7h showed significant potency with IC50 values of 0.02 and 0.01 µM, respectively. The kinetic study revealed that they are noncompetitive inhibitors toward α-glucosidase. Also, fluorescence quenching was used to investigate the interaction of three inhibitors 7a, 7d, and 7h, with α-glucosidase. Accordingly, the binding constants, the number of binding sites, and values of thermodynamic parameters were determined for the interaction of candidate compounds toward the enzyme. Finally, the in silico cavity detection plus molecular docking was performed to find the allosteric site and key interactions between synthesized compounds and the target enzyme.
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Affiliation(s)
- Mina Saeedi
- Medicinal Plants Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
- Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Roshanak Hariri
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Aida Iraji
- Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Central Research Laboratory, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ali Ahmadi
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Somayeh Mojtabavi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Shiva Golshani
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Mohammad Ali Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Tahmineh Akbarzadeh
- Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
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Rezayaraghi F, Jafari-Nodoushan H, Mojtabavi S, Golshani S, Jahandar H, Faramarzi MA. Hybridization of laccase with dendrimer-grafted silica-coated hercynite-copper phosphate magnetic hybrid nanoflowers and its application in bioremoval of gemifloxacin. Environ Sci Pollut Res Int 2022; 29:89255-89272. [PMID: 35843973 DOI: 10.1007/s11356-022-21959-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Laccase was successfully hybridized with polyamidoamine (PAMAM) dendrimer-grafted silica-coated hercynite-copper phosphate magnetic hybrid nanoflowers (MHNFs) to increase the catalytic performance of the enzyme and apply in an effective bioremoval of gemifloxacin. For this purpose, the magnetic nanoparticles (MNPs) of hercynite were covered with a silica layer, and the core-shell SiO2@hercynite was then modified with PAMAM dendrimer to increase the surface area of the carrier for the enzyme attachment. Subsequently, the whole complex was hybridized with laccase and copper phosphate to attain a large surface area (104.3 m2 g-1). The fabricated MHNFs acquired the entrapment yield and efficiency of 90 ± 3% and 66 ± 5%, respectively. The catalytic activity of the fabricated biocatalyst was remained up to 50% after 13 reusability cycles. Approximately 90% of gemifloxacin was removed by the constructed MHNFs after 3 h incubation by adsorption and degradation mechanisms. The biotransformation products were then identified, and degradation pathways were proposed as defluorination, decarboxylation, elimination of a cyclopropyl group, and cleavage of the pyrrolidine moiety. Furthermore, the toxicity of gemifloxacin was effectively diminished against some bacterial strains.
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Affiliation(s)
- Farnoosh Rezayaraghi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
- Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Hossein Jafari-Nodoushan
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Somayeh Mojtabavi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Shiva Golshani
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Hoda Jahandar
- Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Mohammad Ali Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran.
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Shokri M, Mojtabavi S, Jafari-Nodoushan H, Vojdanitalab K, Golshani S, Jahandar H, Faramarzi MA. Laccase-loaded magnetic dialdehyde inulin nanoparticles as an efficient heterogeneous natural polymer-based biocatalyst for removal and detoxification of ofloxacin. Biodegradation 2022; 33:489-508. [PMID: 35809150 DOI: 10.1007/s10532-022-09994-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 06/24/2022] [Indexed: 11/02/2022]
Abstract
An efficient heterogeneous natural polymer-based biocatalyst was fabricated through the immobilization of laccase onto dialdehyde inulin (DAI)-coated silica-caped magnetic nanoparticles (laccase@DAI@SiO2@Fe3O4⋅MNPs). The carrier was developed using SiO2@Fe3O4⋅MNPs and functionalized with DAI. The construction of immobilized laccase was confirmed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Immobilization yield and efficiency were calculated as 61.0 ± 0.3% and 93.0 ± 0.6%, respectively. The immobilized laccase maintained 50% and 85% of its relative activity after 25 repeated cycles and 20 days of storage at 4 °C, respectively. The prepared biocatalyst effectively eliminated ofloxacin, a fluoroquinolone-type antibiotic, with a 63% removal capacity. Besides, antimicrobial activity study on some soil microorganisms involved in the biodegradation of xenobiotics revealed that the laccase-treated ofloxacin resulted in less toxic metabolites. The obtained data indicated that the fabricated biocatalyst is promising for the removal of ofloxacin or other analogs of fluoroquinolones in the environment.
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Affiliation(s)
- Mahtab Shokri
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran.,Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Somayeh Mojtabavi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Hossein Jafari-Nodoushan
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Khashayar Vojdanitalab
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran.,Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Shiva Golshani
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Hoda Jahandar
- Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Mohammad Ali Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran.
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Abstract
The oral cavity is one of the most important routes for local and systemic drug delivery, as it has a large surface, high permeability, and rich blood supply. Oral mucosal drug delivery has some advantages, such as enhancing bioavailability, preventing first-pass metabolism, reducing dose frequency, and non-invasiveness. In recent years, notable oral mucoadhesive patents were introduced to the pharmaceutical field, which indicates promising potentials for therapeutic purposes. Oral mucosal drug delivery can play a key role to deliver the biological drugs, such as antimicrobial peptides. This article gives an overview of oral mucoadhesive drug delivery systems and provides basic principles for the researchers to overcome the problems associated with the formulation design.
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Affiliation(s)
- Shiva Golshani
- Department of Drug and Food Control, Tehran University of Medical Sciences
| | - Alireza Vatanara
- Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Amin
- Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences
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Golshani S, Ali Faramarzi M. Expected Impact of Biosimilars on the Pharmaceutical Companies. Iran J Med Sci 2021; 46:399-401. [PMID: 34539015 PMCID: PMC8438344 DOI: 10.30476/ijms.2021.92314.2356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 08/15/2021] [Accepted: 08/16/2021] [Indexed: 11/10/2022]
Affiliation(s)
- Shiva Golshani
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran,
Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
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Ansari S, Azizian H, Pedrood K, Yavari A, Mojtabavi S, Faramarzi MA, Golshani S, Hosseini S, Biglar M, Larijani B, Rastegar H, Hamedifar H, Mohammadi-Khanaposhtani M, Mahdavi M. Design, synthesis, and α-glucosidase-inhibitory activity of phenoxy-biscoumarin-N-phenylacetamide hybrids. Arch Pharm (Weinheim) 2021; 354:e2100179. [PMID: 34467580 DOI: 10.1002/ardp.202100179] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/08/2021] [Accepted: 08/10/2021] [Indexed: 12/30/2022]
Abstract
Thirteen new phenoxy-biscoumarin-N-phenylacetamide derivatives (7a-m) were designed based on a molecular hybridization approach as new α-glucosidase inhibitors. These compounds were synthesized with high yields and evaluated in vitro for their inhibitory activity against yeast α-glucosidase. The obtained results revealed that a significant proportion of the synthesized compounds showed considerable α-glucosidase-inhibitory activity in comparison to acarbose as a positive control. Representatively, 2-(4-(bis(4-hydroxy-2-oxo-2H-chromen-3-yl)methyl)phenoxy)-N-(4-bromophenyl)acetamide (7f), with IC50 = 41.73 ± 0.38 µM against α-glucosidase, was around 18 times more potent than acarbose (IC50 = 750.0 ± 10.0 µM). This compound was a competitive α-glucosidase inhibitor. Molecular modeling and dynamic simulation of these compounds confirmed the obtained results through in vitro experiments. Prediction of the druglikeness/ADME/toxicity of the compound 7f and comparison with the standard drug acarbose showed that the new compound 7f was probably better than the standard drug in terms of toxicity.
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Affiliation(s)
- Samira Ansari
- CinnaGen Medical Biotechnology Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Homa Azizian
- Department of Medicinal Chemistry, School of Pharmacy, Iran University of Medical Sciences, Tehran, Iran
| | - Keyvan Pedrood
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Yavari
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Somayeh Mojtabavi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad A Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Shiva Golshani
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mahmood Biglar
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Bagher Larijani
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Rastegar
- Cosmetic Products Research Center, Iranian Food and Drug Administration, MOHE, Tehran, Iran
| | - Haleh Hamedifar
- CinnaGen Medical Biotechnology Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Maryam Mohammadi-Khanaposhtani
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Mohammad Mahdavi
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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Noei M, Suzangarzadeh S, Golshani S, Tahan A. The ab initio study and NBO analysis of the solvent dielectric constant effects and the implicit water molecules on the structural stability of the 1-(6-chloroquinoxalin-2-yl)-2-(4-(trifluoromethyl)-2,6-dinitrophenyl) hydrazine. Russ J Phys Chem 2011. [DOI: 10.1134/s0036024411060240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kuehne J, Frankhouse J, Modrall G, Golshani S, Aziz I, Demetriades D, Yellin AE. Determinants of survival after inferior vena cava trauma. Am Surg 1999; 65:976-81. [PMID: 10515547] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Inferior vena cava (IVC) injuries continue to be associated with mortality rates of 21 to 66 per cent despite advances in prehospital, surgical, and critical care. The purpose of this study was to evaluate outcome of patients with IVC injury after treatment at a major urban trauma center and to identify factors predictive of survival. Between 1989 and 1995, 158 patients presented to the Los Angeles County + University of Southern California Medical Center with IVC injuries. One hundred thirty-six patient records were available for review, and 69 data points were collected and analyzed. Mean age was 26 years (range, 6-54), and 122 (90%) patients were male. Mechanism of injury included gunshot in 88 (65%) patients, stab in 23 (17%) patients, shotgun in 7 (5%) patients, and blunt trauma in 18 (13%) patients. The mean Injury Severity Score was 25. Seventy (52%) patients were hypotensive. Eleven (8%) patients died before surgical intervention, and 25 (18%) patients died before operative repair. Repair (79), ligation (20), or observation (1) was accomplished in 100 (74%) patients. Overall survival was 48 per cent and 65 per cent in the 100 patients surviving to operative repair, including 5 of 20 patients requiring IVC ligation. Significant differences (P<0.001) between survivors and nonsurvivors included Injury Severity Score, Glasgow Coma Score, hematocrit, hypotension, emergent thoracotomy, blood loss, level of injury, tamponade, and associated aortic injury. Logistic regression analysis identified hypotension, anatomic level of injury, and associated aortic injury as significant predictors of outcome (P = 0.001). Survival is predominantly determined by severity and anatomic accessibility of the IVC injury and by the absence of associated major vascular injuries. Ligation may control otherwise exsanguinating injuries and should be considered early in the management of complex injuries.
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Affiliation(s)
- J Kuehne
- Los Angeles County+University of Southern California Medical Center, Los Angeles 90033, USA
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Abstract
Necrotizing fasciitis is a rare and potentially fatal infection characterized by rapid and progressive involvement of the fascia and subcutaneous tissues. Early diagnosis, aggressive initial debridement followed by planned redebridements in conjunction with nutritional support and antibiotics remain the mainstay of therapy. We present a case of necrotizing fasciitis of the abdominal wall following a laparoscopically assisted vaginal hysterectomy. Literature is reviewed and discussed with reference to this catastrophic infection in the age of laparoscopic surgery.
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Affiliation(s)
- S Golshani
- Department of Surgery, University of Southern California, 1510 San Pablo Street, Suite 514, Los Angeles, CA 90033, USA
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Abstract
The treatment of 22 patients with vertebral artery injuries was reviewed. Only four patients required an emergency operation. Most of the injuries (13 of 22) were successfully managed by observation. Five patients were managed by angiographic embolization which was successful in three. In three patients with an aneurysm and arteriovenous fistula, proximal embolization of the vascular lesion was not adequate and a suboccipital craniectomy was required for distal ligation. Most vertebral artery injuries can safely be managed without an operation, or by angiographic embolization. Surgical intervention should be reserved for patients with severe bleeding or where embolization has failed.
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Affiliation(s)
- D Demetriades
- Department of Surgery, University of Southern California, USA
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Abstract
The relative importance of the factors that contribute to the bone erosion seen underlying alloplastic implants remains unknown. This study was designed to examine the effects of different alloplastic onlays on the mandible in a rabbit animal model. Three alloplastic materials (soft solid silicone, methyl methacrylate, and porous polyethylene) were examined to determine the importance of implant composition in bone resorption. Thin (1.5-mm) and thick (6-mm) onlays were used to determine the relative importance of implant thickness. Fluorescent markers were administered at different time intervals to evaluate the patterns of new bone formation. A total of 96 implants placed on the mandibles of 16 animals were examined grossly, histologically, and under fluorescent microscopy after 12 and 24 weeks. The frequency and degree of bone erosion were related both to the type of alloplast and to the thickness of the implant. Silicone implants were associated with the greatest amount of bone resorption (p < 0.01). Thicker silicone implants were associated with a greater degree of thinning (p < 0.05). Bone resorption beneath the implants was documented by the presence of osteoclasts actively eroding bone and by changes in the normal patterns of the fluorescent markers. Both the thin methyl methacrylate and the thin porous polyethylene implants had a low incidence of bone thinning. The thick methyl methacrylate implants caused more erosion than the thin implants of the same material, although this was less than the silicone groups. Increasing the thickness of porous polyethylene implants did not adversely affect the underlying bone.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Wellisz
- Division of Plastic Surgery, University of Southern California, Los Angeles, USA
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Abstract
The hexokinase-mitochondrial acceptor theory provides a model of insulin action which unifies the metabolic effects of this hormone and suggests that these result from insulin's stimulatory effect on mitochondrial ATP synthesis. There are similarities between these changes in cells exposed to insulin and in mitochondria of transformed cell lines and cancer cells, where an increased binding of hexokinase to mitochondria is observed. This phenomenon may play a key role in the high rates of glycolysis sustained by cancer cells under aerobic conditions. Structural and functional evidence support the hypothesis that certain growth factors and oncogenes act through stimulation of oxidative phosphorylation via promoting HK binding to mitochondria.
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Affiliation(s)
- S Golshani
- University of Southern California School of Medicine, Los Angeles 90030
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Achong MR, Bayne JR, Gerson LW, Golshani S. Prescribing of psychoactive drugs for chronically ill elderly patients. Can Med Assoc J 1978; 118:1503-8. [PMID: 26459 PMCID: PMC1818121] [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: 12/12/2022]
Abstract
The prescribing of psychoactive drugs for 1431 chronically ill elderly patients being assessed for long-term institutional or community care was surveyed. Psychoactive drugs had been prescribed for about one quarter of the patients; benzodiazepines were the most frequently prescribed group. Judging from the extensive prescribing of flurazepam and chloral hydrate, commonly used hypnotics, the main reason psychoactive drugs were prescribed was to provide night-time sedation. Antidepressants and drugs promoted as useful in improving cognitive function were infrequently prescribed. Commendable prescribing practices included the infrequent use of "cerebral vasodilators" and barbiturates. Questionable prescribing practices included the infrequent use of tricyclic antidepressants in severely depressed patients and the use of tranquilizers in patients described by their attending physician as markedly or extremely withdrawn.
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