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Salunkhe RR, O'Sullivan B, Huang SH, Su J, Xu W, Hosni A, Waldron J, Irish J, de Almeida J, Witterick I, Montero E, Gilbert RW, Razak AA, Zhang L, Brown D, Goldstein D, Gullane P, Tong L, Hahn E. Dawn of Staging for Head and Neck Soft Tissue Sarcoma: Validation of the Novel 8 th Edition AJCC T Classification and Proposed Stage Groupings. Int J Radiat Oncol Biol Phys 2023; 117:S149. [PMID: 37784378 DOI: 10.1016/j.ijrobp.2023.06.567] [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: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) After decades of stagnation, the 8th edition TNM (TNM8) introduced a new T classification for head and neck (HN) soft tissue sarcomas (STS). New size cutoffs of 2 and 4 cm define T1-3, and a novel T4 category is defined by local invasion of adjoining structures. These size cutoffs had been chosen arbitrarily to advance data collection in this unique disease site since literature showed approximately 70% of HN STS did not reach the previous size threshold (5 cm) for the existing T1 category. The definition of the TNM8 T categories also align with mucosal HN cancers. No stage grouping for HN STS was defined since this new classification required more data collection to derive stage groups. This study aims to validate the TNM8 T classification and to propose stage groupings. MATERIALS/METHODS Clinical data of all adult (>16 years) HN STS patients treated from 1988 - 2019 with curative intent in our tertiary cancer center were retrieved from a prospective database, and supplemented with chart review. As per TNM8, cutaneous angiosarcoma, embryonal and alveolar rhabdomyosarcoma, Kaposi sarcoma, and dermatofibrosarcoma protuberans were excluded due to their different behavior. Multivariate analysis (MVA) identified prognostic factors for overall survival (OS). Adjusted hazard ratios (AHR) and recursive partitioning analysis (RPA) were used to derive stage groupings. Stage grouping performance for OS was assessed and also compared against the existing TNM8 groups for non-HN STS. RESULTS A total of 221 patients (N1: 2; M1: 2) were included. Of the 219 M0 patients, 63% were males; median tumor size was 3.0 cm (range: 0.3-14.0); the proportion of TNM8 T1-T4 were 35%, 34%, 26%, and 5%, respectively. Median follow up was 5.9 years. Five-year OS was 79%. MVA confirmed the prognostic value of T category (T4 HR 7.73, 95% CI 3.62-16.5) and grade (G2/3 vs G1 HR 3.7, 95% CI 1.82-7.53), in addition to age (HR 1.03, 95% CI 1.01-1.04) (all p<0.001) for OS. AHR model derived T1-3_Grade 1 as stage 1; T1-3_Grade 2/3 as stage II; and T4_any Grade or any T_N1 as stage III (Table 1); the corresponding 5-year OS was 93%, 73%, and 38%, respectively. Both patients with M1 died within 1.5 years after diagnosis and M1 disease was designated stage IV. The AHR-grouping outperformed the RPA and non-HN TNM8 stage grouping for hazard consistency, hazard discrimination, percent variance explained, hazard difference, and sample size balance. CONCLUSION The novel T4 category introduced in TNM8 is associated with a >7 fold increased risk of death. Grade continues to be a critical prognostic factor in HN STS. The TNM8 HN STS T classifications have been validated, and the proposed new stage groupings with TNM8 incorporating grade have excellent performance for OS.
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Affiliation(s)
- R R Salunkhe
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - B O'Sullivan
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - S H Huang
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - J Su
- Department of Biostatistics, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - W Xu
- Department of Biostatistics, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - A Hosni
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - J Waldron
- Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - J Irish
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - J de Almeida
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - I Witterick
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - E Montero
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - R W Gilbert
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - A A Razak
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - L Zhang
- Mount Sinai Hospital, Toronto, ON, Canada
| | - D Brown
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - D Goldstein
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - P Gullane
- Department of Otolaryngology-Head and Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - L Tong
- Department of Statistical Sciences, University of Toronto, Toronto, ON, Canada
| | - E Hahn
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
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Saha S, Huang SH, O'Sullivan B, Su J, Xu W, Hosni A, Waldron J, Irish J, de Almeida J, Witterick I, Monteiro E, Gilbert RW, Catton CN, Chung P, Brown D, Goldstein D, Razak AA, Gullane P, Hahn E. Outcomes of Head and Neck Cutaneous Angiosarcoma Treated in the IMRT Era. Int J Radiat Oncol Biol Phys 2023; 117:e620-e621. [PMID: 37785859 DOI: 10.1016/j.ijrobp.2023.06.2004] [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: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Clinical behavior, natural history, and varied presentations of cutaneous angiosarcomas of the head and neck region (HN), in conjunction with its rarity, have rendered standardization of treatment elusive. We aimed to assess outcomes and patterns of failure for patients treated with surgery and radiation (Sx+RT), and radiation alone (RT). MATERIALS/METHODS A retrospective review of all HN angiosarcoma patients amenable for upfront Sx or RT in our institution between 2004-2018 was completed. Generally, treatment included Sx when feasible, and RT for large or extensive/ill-defined tumors. Demographic, tumor characteristics, local (LC), regional (RC), distant control (DC), and overall survival (OS), as well as patterns (in-field, marginal, out-of-field) of local failure at 5-year were estimated. Univariate analysis (UVA) was conducted to assess association with outcomes. RESULTS A total of 33 patients were eligible (14 Sx+RT and 19 RT). Tumor locations were: scalp (16, 48%). face (n = 12, 36%), and overlapping (5, 15%). Lesion types were: nodular (n = 23, 70%), flat (n = 4, 12%) and mixed (n = 6, 18%). Tumor size was larger in the RT group (median: 10.00 vs 2.85 cm, p<0.01). RT and Sx+RT patients had otherwise similar baseline characteristics: median age 74.3; male 70%; and ECOG performance status ≤1 85%. RT dose fractionations ranged from 50-70 Gy in 25-35 fractions in the RT group and 50-66 Gy in 25-33 fractions in the Sx+RT group. Four (12%) patients received neoadjuvant chemotherapy. Median follow up was 5.5 years. Five-year LC, RC, DC, and OS for RT vs Sx+RT groups were 68% vs 85% (p = 0.28); 95% vs 86% (p = 0.89); 79% vs 86% (p = 0.39); and 45% vs 55% (p = 0.71), respectively. The in-field/marginal/out-of-field local failure rate at 5 years were 16% vs 7% (p = 0.46), 26% vs 15% (p = 0.41), and 13% vs 0% (p = 0.24) for the RT vs Sx+RT groups, respectively. UVA showed that scalp location and ulceration/bleeding were strong adverse features for OS. Bone invasion was significantly associated with lower DC (Table). Lesion type (nodular/flat/mixed), tumor size, and treatment type (Sx+RT vs RT), were not significantly associated with LC or pattern of local failure. CONCLUSION Scalp tumors, as compared to face, portended poorer prognosis, and ulceration/bleeding and bone invasion were associated with increased distant metastases. Sx+RT was the preferred treatment modality when possible and typically used for smaller and better defined tumors. RT was reserved for larger and extensive/ill-defined disease; despite this, in the IMRT era, RT achieves reasonable rates of control, markedly superior to historical series.
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Affiliation(s)
- S Saha
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - S H Huang
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - B O'Sullivan
- CHUM (The University of Montreal Hospital Centre), Montreal, QC, Canada
| | - J Su
- Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - W Xu
- Department of Biostatistics, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - A Hosni
- Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - J Waldron
- Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - J Irish
- Department of Otolaryngology - Head & Neck Surgery, University Health Network-University of Toronto, Toronto, ON, Canada
| | - J de Almeida
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - I Witterick
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - E Monteiro
- Department of Otolaryngology-Head and Neck Surgery, University of Toronto, Toronto, ON, Canada
| | - R W Gilbert
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - C N Catton
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - P Chung
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - D Brown
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - D Goldstein
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - A A Razak
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - P Gullane
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - E Hahn
- Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada
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Razak AA, Arzoglou V. A frontal external ventricular drain causing a third cranial nerve palsy. Br J Neurosurg 2016; 31:605-606. [PMID: 27241884 DOI: 10.3109/02688697.2016.1173195] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This 47-year-old gentleman presented with acute hydrocephalus secondary to a colloid cyst. Bilateral external ventricular drains (EVDs) were inserted. The patient developed a third nerve palsy during post-operative period - cranial imaging demonstrated the tip of an EVD in this vicinity. The palsy recovered completely on slight withdrawal of the EVD.
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Affiliation(s)
- A A Razak
- a Department of Neurosurgery , Hull Royal Infirmary , Anlaby Road , Hull , HU3 2JZ , United Kingdom of Great Britain and Northern Ireland
| | - V Arzoglou
- a Department of Neurosurgery , Hull Royal Infirmary , Anlaby Road , Hull , HU3 2JZ , United Kingdom of Great Britain and Northern Ireland
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Oaknin A, Plummer R, Salazar R, Robinson A, Pardo B, Razak AA, Cuadra C, Flores L, Izquierdo MA, Calvert H. Phase I combination study of plitidepsin and carboplatin in advanced solid tumours. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.2558] [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: 11/20/2022] Open
Abstract
2558 Background: Plitidepsin is a cyclic depsipeptyde isolated from the marine tunicate Aplidium albicans, nowadays manufactured by synthesis. It is a rapid and potent inductor of apoptosis. In phase I trials, muscle (myalgia and CPK increase) and liver toxicities were dose-limiting and preliminary activity was observed in malignant melanoma, renal, head and neck, lung, neuroendocrine, colorectal and hematological malignancies. Preclinical synergism with carboplatin (CBCDA) against solid tumors and acute leukaemia suggest plitidepsin can reverse platinum chemoresistance in vivo through reduction of glutathione levels. This phase I trial was initiated in order to evaluate the safety, pharmacokinetics (PK) and antitumour activity of the combination of CBCDA and weekly administration of plitidepsin (Recommended dose (RD) in monotherapy: 3.2 mg/m2). Methods: Patients (pts) with advanced solid tumours and good performance status (WHO PS = 2) were enrolled. Plitidepsin was given over 1 hr infusion on days 1 , 8 and 15 every 4 weeks followed by CBDCA (AUC 5) as a 1 hr infusion on day 1. Dose levels planned for plitidepsin were 1.8, 2.4 and 3.0 mg/m2 in cohorts of 3 pts. PK sampling was performed during the first cycle (cy) of treatment. Results: 18 pts have been treated to date (8M/10F). Median age (range): 59 (39–73) yrs. WHO PS>0: 3pts. Tumour types included colorectal (5), malignant melanoma (4), ovary (2), other gastrointestinal tumors (7). No DLT was observed at plitidepsin 1.8 and 2.4 mg/m2 (3 pts treated in each cohort). Two out of 5 pts exhibited DLT at pltidepsin 3.0 mg/m2, consisting of delay of second cy >2 weeks (grade 3 transaminitis and grade 3 thrombocytopenia) and omission of second infusion in first cy (grade 3 ALT increase). Plitidepsin at 2.4 mg/m2 was expanded to 8 pts. There were 4 pts with stable disease (cholangio, liver, colorectal, gatro-esophageal junction and esophagus carcinomas). Conclusions: The RD for the combination is plitidepsin 2.4 mg/m2 (0.8 mg/m2 lower than in monotherapy) days 1, 8 and 15 every 4 weeks followed by CBDCA (AUC 5). DLTs of the combination at the highest dose were different vs single plitidepsin (liver and haematological vs muscular). PK analyses from the three cohorts to detect interactions and updated safety data for the RD cohort are in progress. [Table: see text]
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Affiliation(s)
- A. Oaknin
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - R. Plummer
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - R. Salazar
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - A. Robinson
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - B. Pardo
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - A. A. Razak
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - C. Cuadra
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - L. Flores
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - M. A. Izquierdo
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
| | - H. Calvert
- Institut Català d’Oncologia, L’Hospitalet de Llobregat (Barcelona), Spain; Hospital Nothern Centre for Cancer Medical Onc, Newcastle, United Kingdom; PharmaMar SAU, Colmenar Viejo - Madrid, Spain
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Memon MS, Yunus N, Razak AA. Some mechanical properties of a highly cross-linked, microwave-polymerized, injection-molded denture base polymer. INT J PROSTHODONT 2001; 14:214-8. [PMID: 11484567] [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: 02/21/2023]
Abstract
PURPOSE The impact strength and the flexural properties of denture base materials are of importance in predicting their clinical performance upon sudden loading. This study compares the impact and transverse strengths and the flexural modulus of three denture base polymers. MATERIALS AND METHODS The investigation included a relatively new microwave-polymerized polyurethane-based denture material processed by an injection-molding technique, a conventional microwave-polymerized denture material, and a heat-polymerized compression-molded poly(methyl methacrylate) (PMMA) denture material. Impact strength was determined using a Charpy-type impact tester. The transverse strength and the flexural modulus were assessed with a three-point bending test. The results were subjected to statistical analysis using a one-way analysis of variance and the Scheffé test for comparison. RESULTS The impact strength of the microwave-polymerized injection-molded polymer was 6.3 kl/m2, while its flexural strength was 66.2 MPa. These values were lower than those shown by the two compression-molded PMMA-based polymers. The differences were statistically significant. The flexural modulus of the new denture material was 2,832 MPa, which was higher than the conventional heat-polymerized polymer but was comparable to the other microwave-polymerized PMMA-based polymer. The difference in the flexural modulus was statistically significant. CONCLUSION In terms of the impact and flexural strengths, the new microwave-polymerized, injection-molded, polyurethane-based polymer offered no advantage over the existing heat- and microwave-polymerized PMMA-based denture base polymers. However, it has a rigidity comparable to that of the microwave-polymerized PMMA polymer.
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Affiliation(s)
- M S Memon
- Department of Prosthetic Dentistry, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Abstract
A strain of Fusarium oxysporum tolerated copper in the growth medium at concentrations up to 600 mg/L. The optimum growth was obtained at 200 mg Cu/L. The mycelium acquired a blue color in the presence of copper. The copper content of isolated cell walls obtained from mycelium grown in the presence of 600 mg Cu/L was 1.5 times higher than that of cell walls obtained from mycelium grown at 200 mg Cu/L and it contained 2.2 and 3.3% copper at 200 and 600 mg Cu/L, respectively. The amount of protein and total sugars increased in both the mycelium and its isolated cell walls in the presence of copper in the growth medium, chitin was also increased in the cell wall, reaching its maximum amount at 200 mg Cu/L--about 2.4 times higher than without copper. Most of amino acid concentrations in the cell wall were increased in the presence of 200 mg Cu/L and decreased above this concentration. Isoleucine, leucine, tyrosine, phenylalanine, and arginine showed the highest increase at this concentration. The altered cell walls obtained from mycelium grown at 200 and 400 mg Cu/L could rebind individual metals more than the control cell walls could. Rebinding of individual metals was in the order Zn > Fe > Ni > Cu > Co. Rebinding of copper by isolated cell walls depended on pH and temperature.
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Affiliation(s)
- M A Hefnawy
- Botany Department, Faculty of Science, Menoufia Unviersity, Shebin El-Kom, Egypt
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Abstract
The transverse bend test and surface microhardness test were used to determine the optimum curing cycle for a light- and heat-cured composite inlay material. Specimens were light-cured (control) and light- and heat-cured using the following temperatures: 50 degrees C for 5 min; 50 degrees C for 10 min; 100 degrees C for 1 min; 100 degrees C for 5 min; 100 degrees C for 10 min; and 100 degrees C for 15 min. Heat-curing in boiling water at 100 degrees C for at least 1 min significantly improved the transverse strength, modulus of elasticity and surface microhardness compared to light-curing only or at 50 degrees C. The curing cycle of 100 degrees C for 5 min is considered the most appropriate.
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Affiliation(s)
- A A Razak
- Department of Oral and Dental Science, University of Bristol Dental School, UK
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Abstract
STATEMENT OF PROBLEM Dimensional accuracy of a composite inlay restoration is important to ensure an accurate fit and to minimize cementation stresses. PURPOSE OF STUDY A method was developed to measure dimensional accuracy and stability of a composite inlay. MATERIAL AND METHODS A standard Class II (MOD) inlay cavity stainless steel mold was made with six circular indentations placed on the occlusal floor of the cavity and four indentations on each gingival floor to act as datum points in the measurement of linear polymerization shrinkage. The inlay restorations were prepared from an inlay-onlay composite material of different filler contents (50%, 65%, and 79% by weight). For each filler content group, three curing methods were used: light curing only, light curing and heat curing at 100 degrees C for 5 minutes, and light curing and heat curing at 100 degrees C for 5 minutes and then storage in distilled water for 7 days. The accuracy of the MOD inlays was determined by measuring the shrinkage of the restoration on the occlusal floor areas and the gingival seats. RESULTS The results demonstrated an inverse linear relationship between filler content and polymerization shrinkage. There was a tendency for the light-curing and heat-curing method to show an increase in polymerization shrinkage. An expansion was recorded between the mesial and distal boxes when the specimens were soaked in water for 7 days. CONCLUSIONS This study suggested that the inlay mold limits the physical shrinkage that can occur between the mesial and distal axial walls of the inlay restoration because the inlay cannot shrink to a smaller dimension than the mold. Water sorption then causes hygroscopic expansion, which enlarges the distance between the mesial and distal walls.
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Affiliation(s)
- A A Razak
- Department of Conservative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
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Abstract
Mycotoxin production from Penicillium expansum was effected by the 'biocontrol enhancer' 2-deoxy-D-glucose (DOG). Citrinin and gentisyl alcohol were produced in higher amounts, whereas patulin was inhibited, which represents a differential effect on the polyketide metabolic pathway. These effects have implications for the use of DOG in biocontrol.
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Affiliation(s)
- N F Abo-Dahab
- International Mycological Institute, Egham, Surrey, UK
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Abstract
Aspergillus terreus was cultivated on Harrold's medium supplemented with 0.1% (w/v) cadmium chloride as well as on sulfur free medium amended with 0.1% (w/v) sodium selenite and potassium tellurite separately. The cell free extract of the fungus for each treatment was fractionated on a column packed with Sephadex G 75. The results demonstrated the ability of the fungus to synthesize several cadmium, selenium, and tellurium-binding proteins as well as metallothionein. The results suggested the biosynthesis of heavy metals chelators as well. The amino acids composition of a cadmium-binding metallothionein revealed the presence of high levels of both aromatic and sulfur amino acids in the hydrolysate.
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Affiliation(s)
- I M Abbass
- Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt
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Abstract
Aspergillus funiculosus was isolated from rotted banana fruits, whereas Alternaria tenuis and Fusarium sp. were isolated from rotted tomato fruits. The isolated fungi tolerated relatively high levels of the fungicide, Dithane, up to 2560 ppm on solid medium, but grew well at 40 ppm when supplemented with liquid medium. They are able to tolerate selenite up to 2% (w/v) sodium selenite. A. funiculosus showed no growth in the presence of mixture of 2.5 ppm selenium and 20 ppm Dithane, whereas Fusarium sp. failed to grow at 2.5 ppm selenium and 10 ppm Dithane, or at 10 ppm of each. Nevertheless, Alternaria tenuis is more tolerant; it showed growth in the presence of relatively high levels of selenium and Dithane; up to 10 ppm selenium and 40 ppm Dithane, however, its growth was inhibited by the presence of a mixture of both. The results suggested new form of highly active fungicides. Selenium as an essential nutrient at such very low concentrations, as well as the application of very low concentrations of the fungicide, would certainly reduce the hazardous effect of such pollutant in the environment.
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Affiliation(s)
- A A Razak
- Department of Botany, Faculty of Science, Al-Azhar University, Cairo, Egypt
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Abstract
A selenium-dependent Bacillus sp. is able to grow well up to 3% sodium selenite-containing media. The bacterium completely failed to grow on media devoid of selenium. The presence of selenium in the growth media increased the bacterial contents of proteins, carbohydrates, and lipids. The highest quantities of amino acids were detected at 2% sodium selenite-containing media. The bacterium metabolized selenite into several protein selenoamino acids such as selenomethionine and selenocysteine/selenocystine, as well as nonprotein selenoamino acids, such as selenocystathionine. Several phosphoamino acids were detected in the presence of elevated levels of selenium. The synthesized protein seems not to be affected by the presence of selenium.
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Affiliation(s)
- A A Razak
- Department of Botany, Faculty of Science, Al-Azhar University, Cairo, Egypt
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Abstract
A selenium-dependent bacterium, Bacillus sp., failed to grow on selenium-free media. However, it is able to grow at high concentrations of sodium selenite containing media up to 3% (w/v). It accumulated extraordinary high quantities of selenium, 432 ppm/mL. The bacterium generated the transformation of inorganic selenium into volatile selenium form(s) into the atmosphere. The biological release of volatile selenium basically depended on several factors: incubation temperature, pH, incubation periods, and substrate concentration. Maximal quantity of the volatile selenium form was obtained at 30 degrees C, pH 7, and 1% (w/v) sodium selenite.
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Affiliation(s)
- A A Razak
- Department of Botany, Faculty of Science, Al-Azhar University, Medinet Nasr, Cairo, Egypt
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Abstract
Aspergillus carbonarius and a strain of Penicillium, a cadmium tolerant fungi, are able to metabolize cadmium chloride up to 2% (w/v). Their amino acids analysis on cadmium free and cadmium chloride containing media indicated certain disorders in their metabolic activities. Cystathionine was only detected in both fungi in the presence of cadmium chloride. However, cadmium was incorporated into several types of low and high molecular weight proteins. The amino acids hydrolyzates of a cadmium containing protein are characterized by the presence of high levels of sulfur amino acids; cysteine and methionine. Ethylasparagine was detected in the hydrolyzate of that cadmium containing protein as well.
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Affiliation(s)
- A A Razak
- Department of Botany, Faculty of Science, Al-Azhar University, Cairo, Egypt
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Abstract
Aspergillus fumigatus, Aspergillus terreus, and Penicillium chrysogenum, a tellurium tolerant fungi, are able to grow on sulfur free medium amended with 0.2% (w/v) tellurite. Tellurium was incorporated into several types of low and high molecular weight proteins. The newly detected telluro-proteins contained an extraordinary high level of tellurium, as well as telluro-cysteine, telluro-cystine, telluro-methionine, and serine.
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Affiliation(s)
- S E Ramadan
- Department of Botany, Faculty of Science, Al-Azhar University, Cairo, Egypt
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Razak IA, Razak AA. Patterns of tooth vulnerability to caries in 20-24-year-old subjects. Odontostomatol Trop 1988; 11:145-8. [PMID: 3272009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Abstract
Aspergillus carbonarius and a strain of Penicillium are able to grow on Harrold's agar media amended with different concentrations of cadmium chloride up to 2.5% (w/v). Considerable quantities of cadmium were absorbed by both fungi. A. carbonarius absorbed more cadmium than the Penicillium sp. did, under the same culturing conditions. In the presence of cadmium, the determined cellular contents of proteins, lipids, and carbohydrates were extraordinary high, whereas the activities of certain enzymes, lipases, amylases, and proteases were inhibited. The fungal rate of growth and sporulations were mostly suppressed. Conidiations were inhibited at lowest concentrations. At 1% Cd Cl2, A. carbonarius produced malformed conidiophores, whereas the Penicillium sp. was less affected. At higher concentrations conidiophores production were entirely suppressed and several hyphal swellings were produced.
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Affiliation(s)
- S E Ramadan
- Department of Botany, Faculty of Science, Al-Azhar University, Medinet Nasr, Cairo, Egypt
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18
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Abstract
Fusarium sp. was isolated from Sinai soil at Egypt. It showed tendency to tolerate high concentrations of selenium in the form of sodium selenite up to 3.5% (w/v). The microscopic examination revealed some morphological distortions. However, the fungus was capable to circumvent the toxic effect of selenium. The fungus possess strong reducing ability as high quantities of elemental selenium were precipitated within the fungal cells as well as on the surface of the fungal hyphae and spores. The presence of selenium increased the cellular contents of carbohydrates, proteins, and lipids. Labeling studies indicate the incorporation of selenite into certain amino acids: selenocysteine and selenocysteic acid. Moreover, the presence of selenium induced the biosynthesis of several types of low molecular weight proteins. The results demonstrated different modes of detoxification of selenium toxicity.
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Affiliation(s)
- S E Ramadan
- Department of Botany, Faculty of Science, Al-Azhar University, Cairo, Egypt
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19
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Abstract
Aspergillus terreus, a moderately selenium-tolerant fungus, metabolized Se-selenite into several protein seleno-amino acids: selenomethionine and selenocysteine, as well as, nonprotein seleno-amino acids, selenocystathionine, and y-glutamyl selenomethyl selenocysteine. The results indicate the failure of the fungus to discriminate between sulphur and selenium. Selenium was also incorporated into several proteins of different molecular weights, mostly of low molecular weight proteins. Labeled studies showed the presence of high levels of selenomethionine and selenocysteine in the protein hydrolysate. The actual incorporation of protein seleno-amino acids into the fungal protein was proven. The results demonstrated a finding that detracts from previous held views.
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Affiliation(s)
- S E Ramadan
- Faculty of Science for Girls, Al-Azhar University, Medinet Nasr, Cairo, Egypt
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20
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Razak AA. The proximal finishing of posterior composite restorations. Singapore Dent J 1984; 9:11-4. [PMID: 6599642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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21
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Razak IA, Razak AA. Caries susceptibility of first permanent molars in 1808 schoolchildren aged 7-12 years. Singapore Dent J 1984; 9:23-5. [PMID: 6599645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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22
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Razak IA, Razak AA. Students' perception about the etiology and prevention of dental caries and gingivitis. Singapore Dent J 1983; 8:53-7. [PMID: 6596723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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