15 results on '"Hamama S"'
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2. Limits to host colonization and speciation in a radiation of parasitic finches
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Jamie, GA, Hamama, S, Moya, C, Kilner, RM, Spottiswoode, CN, Kilner, Rebecca [0000-0003-1159-0758], Spottiswoode, Claire [0000-0003-3232-9559], and Apollo - University of Cambridge Repository
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3109 Zoology ,Infectious Diseases ,3103 Ecology ,FOS: Health sciences ,14 Life Below Water ,31 Biological Sciences ,Biotechnology - Abstract
Parasite lineages vary widely in species richness. In some clades, speciation is linked to the colonization of new hosts. This is the case in the indigobirds and whydahs (Vidua), brood-parasitic finches whose nestlings mimic the phenotypes of their specific hosts. To understand the factors limiting host colonization and, therefore, speciation, we simulated the colonization of a host using cross-fostering experiments in the field. Despite DNA barcoding suggesting that host species feed their chicks similar diets, nestling Vidua had low survival in their new host environment. Nestling Vidua did not alter their begging calls plastically to match those of the new hosts and were fed less compared to both host chicks and to Vidua chicks in their natural host nests. This suggests that a key hurdle in colonizing new hosts is obtaining the right amount rather than the right type of food from host parents. This highlights the importance of mimetic nestling phenotypes in soliciting feeding from foster parents and may explain why successful colonizations tend to be of hosts closely related to the ancestral one. That nonmimetic chicks are fed less but not actively rejected by host parents suggests how selection from hosts can be sufficiently intense to cause parasite adaptation, yet sufficiently relaxed that parasitic chicks can sometimes survive in and colonize new host environments even if they lack accurate mimetic phenotypes. The difficulties of soliciting sufficient food from novel foster parents, together with habitat filters, likely limit the colonization of new hosts and, therefore, speciation in this parasite radiation.
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- 2021
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3. Keanekaragaman Serangga Permukaan Tanah di Sekitar Perkebunan Desa Cot Kareung Kecamatan Indrapuri Kabupaten Aceh Besar
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Hamama, S. F. (Syarifah), Hamama, S. F. (Syarifah), Sasmita, I. (Irma), Hamama, S. F. (Syarifah), Hamama, S. F. (Syarifah), and Sasmita, I. (Irma)
- Abstract
The research about the soil insect diversity in plantation area of Cot Kareung village, Kecamatan Indrapuri Kabupaten Aceh Besar, had been done from 04 May to June 2016. The purpose of this studyis to determinethe diversity ofsoilinsectsaroundthe plantationarea. The method that usedinthis research was descriptiveexploratorymethod, by utilizing the data sourcesin nature. Sample location was determine by usingstation methode, becausethe heterogeneous condition of sample population. The systematic samplingtechniqueby dividingthe location into threestation. Thesampling sitewas made3points. The results ofthis studyshowedthe numbers of the soil insect in station I, II and III are 381, 312 and 299 individual respectively. The data was found there are 5 order, Hymenoptera, Orthoptera, Heminoptera, BlattariaandDermaptera. Order that have the highest number of soil insect is Hymenoptera(957 individual). Groundinsectdiversityindexatstation Iis0.869, station IIis0.659andstation IIIis1.063with an average of2.591.Â
- Published
- 2017
4. Kajian Terhadap Sikap Guru Dan Perilaku Siswa Pada Mata Pelajaran Biologi Berdasarkan Gender Di SMP Negeri 1 Dan SMP Negeri 6 Banda Aceh
- Author
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Hamama, S. F. (Syarifah), Hamama, S. F. (Syarifah), Hamama, S. F. (Syarifah), and Hamama, S. F. (Syarifah)
- Abstract
This article report students' perception on their teacher interpersonal behaviour and their attitude toward Biology based on gender in two Lower Secondary Schools (SMP Negeri 1 and SMP Negeri 6) in Banda Aceh. The data were collected using two questionnaires, there are, the Indonesian version of The Teacher Interaction (QTI) and Test of Biology Related Attitude (TOBRA). This study has been done from May to November 2015. A total sample of 243 Students in grade 8 and 9, responded to the questionnaires. The sample was chosen based on Krejcie-Morgan table. This result found that the questionnaires are valid and reliable. There are are no significant differences between male and female perception on teacher interpersonal behaviour, except on Students Responsibility and Admonishing. This study also confirmed that relationship between student perception on teacher interpersonal behaviour and their attitude toward biology is not occurred. Student enjoyment is not related to all scale, except on Strict. Based on regression analysis, it was found that the attitude of the teacher in QTI scales can not be used to predict the students' attitude toward Biology.
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- 2016
5. Nosocomial infections and infectious risks related to hospital environment
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Saouide El Ayne Nabila, Hami Hinde, Hamama Samir, Coulibaly Sanou Khô, Mokhtari Abdelrhani, and Soulaymani Abdelmajid
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nosocomial infections ,hospital environment ,morocco ,Environmental sciences ,GE1-350 - Abstract
Introduction: The fight against nosocomial infections, particularly those linked to environmental germs, is one of the priorities of health establishments. Microbiological control of the hospital environment is an essential element of the strategy for the fight against these infections. The aim of this study is to determine the microbial ecology of hospital surfaces and medical devices. Methods: This is a study, which was carried out in the El Idrissi hospital in Kénitra. For the microbiological control of surfaces, we opted for the swab technique: the search for specific germs on flat surfaces and in areas that are difficult to access and not flat. Results: Among the bacteria most frequently responsible for isolated nosocomial infections: Bacillus (28%) and coagulase-negative staphylococci (27%) were predominant, followed by Staphylococcus aureus (19%), Klebsiella pneumoniae (17%), Pseudomonas aeruginosa (5%), Enterobacter cloacae (3%) and Proteus vulgaris (1%).The overall distribution of germs by department showed their predominance in intensive care units (30%), traumatology (11%), emergencies (11%) and in operating rooms (9%). Conclusion: Periodic microbiological controls must be put in place in order to identify any contamination, to carry out preventive actions, procedures and a fundamental approach for the control of infectious risks in the hospital.
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- 2021
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6. Highly virulent avian brood-parasitic species show elevated embryonic metabolic rates at specific incubation stages compared to less virulent and non-parasitic species.
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McClelland SC, Lund J, Dixit T, Hamama S, McClean LA, Spottiswoode CN, White CR, Louder MIM, Hauber ME, Honza M, and Portugal SJ
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- Animals, Embryo, Nonmammalian metabolism, Virulence, Nesting Behavior, Energy Metabolism, Birds parasitology, Birds embryology, Host-Parasite Interactions
- Abstract
As the avian embryo grows and develops within the egg, its metabolic rate gradually increases. Obligate avian brood-parasitic birds lay their eggs in the nests of other species to avoid the costs of parental care, and all but one of these brood-parasitic species are altricial at hatching. Yet the chicks of some altricial brood-parasitic species perform the physically demanding task of evicting, stabbing or otherwise killing host progeny within days of hatching. This implies a need for high metabolic rates in the embryo, just as precocial species require. Using flow-through respirometry in situ , we investigated embryonic metabolic rates in diverse avian brood parasite lineages which either kill host offspring (high virulence) or share the nest with host young (low virulence). High-virulence brood parasite embryos exhibited higher overall metabolic rates than both non-parasitic (parental) species and low-virulence parasites. This was driven by significantly elevated metabolic rates around the halfway point of incubation. Additionally, a fine-scale analysis of the embryos of a host-parasitic pair showed faster increases in metabolic rates in the parasite. Together these results suggest that the metabolic patterns of the embryos of high-virulence parasites facilitate their early-life demands.
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- 2024
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7. When perfection isn't enough: host egg signatures are an effective defence against high-fidelity African cuckoo mimicry.
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Lund J, Dixit T, Attwood MC, Hamama S, Moya C, Stevens M, Jamie GA, and Spottiswoode CN
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- Animals, Nesting Behavior, Biological Evolution, Phenotype, Ovum, Host-Parasite Interactions, Passeriformes genetics, Parasites
- Abstract
Most mimicry systems involve imperfect mimicry, whereas perfect and high-fidelity mimicry are rare. When the fidelity of mimicry is high, mimics might be expected to have the upper hand against their antagonists. However, in coevolving systems, diversification of model phenotypes may provide an evolutionary escape, because mimics cannot simultaneously match all model individuals in the population. Here we investigate high-fidelity mimicry in a highly specialized, Afrotropical brood parasite-host system: the African cuckoo and fork-tailed drongo. Specifically, we test whether host egg polymorphisms are an effective defence against such mimicry. We show, using a combination of image analysis, field experiments and simulations, that: (1) egg colour and pattern mimicry of fork-tailed drongo eggs by African cuckoos is near-perfect on average; (2) drongos show fine-tuned rejection of foreign eggs, exploiting unpredictable pattern differences between parasitic eggs and their own; and (3) the high degree of interclutch variation (polymorphic egg 'signatures') exhibited by drongos gives them the upper hand in the arms race, with 93.7% of cuckoo eggs predicted to be rejected, despite cuckoos mimicking the full range of drongo egg phenotypes. These results demonstrate that model diversification is a highly effective defence against mimics, even when mimicry is highly accurate.
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- 2023
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8. Sex differences in body composition in youth with type 1 diabetes and its predictive value in cardiovascular disease risk assessment.
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Brener A, Hamama S, Interator H, Ben Simon A, Laurian I, Dorfman A, Chorna E, Yackobovitch-Gavan M, Oren A, Eyal O, and Lebenthal Y
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- Humans, Male, Female, Adolescent, Child, Young Adult, Adult, Sex Characteristics, Body Composition, Insulin, Risk Assessment, Body Mass Index, Diabetes Mellitus, Type 1 complications, Cardiovascular Diseases diagnosis, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology
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Background: Women with type 1 diabetes (T1D) are more susceptible than men to cardiovascular disease (CVD). Signs of increased risk may already appear among adolescent girls., Objectives: We explored the contribution of body composition to the development of CVD risk factors among youth with T1D., Methods: One hundred and eighty nine subjects with T1D (mean age 15.3 ± 5.1 years, 55% boys) followed between January 2018-January 2022 were included in this observational study. Sociodemographic and clinical data were extracted from medical files. Body composition was measured by bioelectrical impedance analysis, and muscle-to-fat ratio (MFR) z-scores were calculated. Logistic regression model assessed the association between body composition (MFR z-scores) and evidence of CVD risk factors., Results: Females were characterised by higher median BMI z-scores (0.47 vs. 0.04, p = 0.012), higher fat and truncal fat percentage levels (p ≤ 0.001) and lower median MFR z-scores (-0.64 vs. -0.25, p ≤ 0.001), higher median triglyceride (TG) levels (71 vs. 61 mg/dl, p = 0.05), longer disease duration to initiation of insulin pump therapy (p = 0.041), and more time spent in marked hypoglycemia (1 vs. 0.2%, p = 0.007) than males. Males' MFR z-scores were associated with several diabetes-related parameters (age at diagnosis, CGM metrics, HbA1c and insulin dose), while the females'' MFR z-scores were linked to the atherogenic dyslipidemia index (TG:HDL ratio). The odds for CVD risk factors were doubled for every 1 SD decrease in MFR z-score (OR = 0.50, CI [0.30-0.84], p = 0.009) and also increased with age (OR = 1.07, CI [1.004-1.148], p = 0.038)., Conclusions: Body composition measurement has a predictive value in CVD risk assessment in youth with T1D, with unique characteristics and influences in each sex., (© 2022 The Authors. Diabetes/Metabolism Research and Reviews published by John Wiley & Sons Ltd.)
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- 2023
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9. Genetic architecture facilitates then constrains adaptation in a host-parasite coevolutionary arms race.
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Spottiswoode CN, Tong W, Jamie GA, Stryjewski KF, DaCosta JM, Kuras ER, Green A, Hamama S, Taylor IG, Moya C, and Sorenson MD
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- Animals, Pigmentation genetics, Adaptation, Physiological genetics, Biological Evolution, Biological Mimicry genetics, Maternal Inheritance, Nesting Behavior, Passeriformes genetics, Passeriformes physiology
- Abstract
In coevolutionary arms races, interacting species impose selection on each other, generating reciprocal adaptations and counter adaptations. This process is typically enhanced by genetic recombination and heterozygosity, but these sources of evolutionary novelty may be secondarily lost when uniparental inheritance evolves to ensure the integrity of sex-linked adaptations. We demonstrate that host-specific egg mimicry in the African cuckoo finch Anomalospiza imberbis is maternally inherited, confirming the validity of an almost century-old hypothesis. We further show that maternal inheritance not only underpins the mimicry of different host species but also additional mimetic diversification that approximates the range of polymorphic egg “signatures” that have evolved within host species as an escalated defense against parasitism. Thus, maternal inheritance has enabled the evolution and maintenance of nested levels of mimetic specialization in a single parasitic species. However, maternal inheritance and the lack of sexual recombination likely disadvantage cuckoo finches by stifling further adaptation in the ongoing arms races with their individual hosts, which we show have retained biparental inheritance of egg phenotypes. The inability to generate novel genetic combinations likely prevents cuckoo finches from mimicking certain host phenotypes that are currently favored by selection (e.g., the olive-green colored eggs laid by some tawny-flanked prinia, Prinia subflava, females). This illustrates an important cost of coding coevolved adaptations on the nonrecombining sex chromosome, which may impede further coevolutionary change by effectively reversing the advantages of sexual reproduction in antagonistic coevolution proposed by the Red Queen hypothesis.
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- 2022
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10. Embryo movement is more frequent in avian brood parasites than birds with parental reproductive strategies.
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McClelland SC, Reynolds M, Cordall M, Hauber ME, Goymann W, McClean LA, Hamama S, Lund J, Dixit T, Louder MIM, Safari I, Honza M, Spottiswoode CN, and Portugal SJ
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- Adaptation, Physiological, Animals, Biological Evolution, Birds parasitology, Host-Parasite Interactions, Nesting Behavior, Reproduction, Parasites
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Movement of the embryo is essential for musculoskeletal development in vertebrates, yet little is known about whether, and why, species vary. Avian brood parasites exhibit feats of strength in early life as adaptations to exploit the hosts that rear them. We hypothesized that an increase in embryonic movement could allow brood parasites to develop the required musculature for these demands. We measured embryo movement across incubation for multiple brood-parasitic and non-parasitic bird species. Using a phylogenetically controlled analysis, we found that brood parasites exhibited significantly increased muscular movement during incubation compared to non-parasites. This suggests that increased embryo movement may facilitate the development of the stronger musculoskeletal system required for the demanding tasks undertaken by young brood parasites.
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- 2021
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11. Multimodal mimicry of hosts in a radiation of parasitic finches.
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Jamie GA, Van Belleghem SM, Hogan BG, Hamama S, Moya C, Troscianko J, Stoddard MC, Kilner RM, and Spottiswoode CN
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- Animals, Animals, Newborn, Phenotype, Pigmentation genetics, Vocalization, Animal, Zambia, Biological Mimicry genetics, Finches genetics, Genetic Speciation, Nesting Behavior
- Abstract
Brood parasites use the parental care of others to raise their young and sometimes employ mimicry to dupe their hosts. The brood-parasitic finches of the genus Vidua are a textbook example of the role of imprinting in sympatric speciation. Sympatric speciation is thought to occur in Vidua because their mating traits and host preferences are strongly influenced by their early host environment. However, this alone may not be sufficient to isolate parasite lineages, and divergent ecological adaptations may also be required to prevent hybridization collapsing incipient species. Using pattern recognition software and classification models, we provide quantitative evidence that Vidua exhibit specialist mimicry of their grassfinch hosts, matching the patterns, colors and sounds of their respective host's nestlings. We also provide qualitative evidence of mimicry in postural components of Vidua begging. Quantitative comparisons reveal small discrepancies between parasite and host phenotypes, with parasites sometimes exaggerating their host's traits. Our results support the hypothesis that behavioral imprinting on hosts has not only enabled the origin of new Vidua species, but also set the stage for the evolution of host-specific, ecological adaptations., (© 2020 The Authors. Evolution published by Wiley Periodicals LLC on behalf of The Society for the Study of Evolution.)
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- 2020
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12. MiR-210: A potential therapeutic target against radiation-induced enteropathy.
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Hamama S, Noman MZ, Gervaz P, Delanian S, and Vozenin MC
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- Antioxidants therapeutic use, Cells, Cultured drug effects, Cells, Cultured metabolism, Drug Therapy, Combination, Fibrosis drug therapy, Fibrosis metabolism, Humans, Hypoxia metabolism, Intestinal Diseases metabolism, MicroRNAs antagonists & inhibitors, Molecular Targeted Therapy methods, Myocytes, Smooth Muscle drug effects, Myocytes, Smooth Muscle metabolism, RNA metabolism, RNA, Mitochondrial, Radiation Injuries metabolism, Radiotherapy adverse effects, alpha-Tocopherol therapeutic use, Intestinal Diseases drug therapy, MicroRNAs metabolism, Pentoxifylline therapeutic use, Platelet Aggregation Inhibitors therapeutic use, Radiation Injuries drug therapy, Radiation-Protective Agents therapeutic use
- Abstract
A previously undescribed and robust miR210 overexpression is shown in intestinal samples obtained from patients with radiation enteropathy and fibrotic cultured cells. In addition, miR-210 overexpression is repressed by antifibrotic treatment combining pentoxifylline and α-tocopherol., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)
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- 2014
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13. IGF-1R targeting increases the antitumor effects of DNA-damaging agents in SCLC model: an opportunity to increase the efficacy of standard therapy.
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Ferté C, Loriot Y, Clémenson C, Commo F, Gombos A, Bibault JE, Fumagalli I, Hamama S, Auger N, Lahon B, Chargari C, Calderaro J, Soria JC, and Deutsch E
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- Animals, Antibodies, Monoclonal administration & dosage, Antibodies, Monoclonal, Humanized, Cell Proliferation drug effects, Cisplatin administration & dosage, Down-Regulation, Female, Humans, Immunohistochemistry, Lung Neoplasms genetics, Lung Neoplasms metabolism, Mice, Mice, Nude, Molecular Targeted Therapy, Proto-Oncogene Proteins c-akt metabolism, Receptor, IGF Type 1 immunology, Receptor, IGF Type 1 metabolism, Signal Transduction, Small Cell Lung Carcinoma genetics, Small Cell Lung Carcinoma metabolism, Survival Analysis, Xenograft Model Antitumor Assays, Antibodies, Monoclonal pharmacology, Antineoplastic Combined Chemotherapy Protocols pharmacology, Cisplatin pharmacology, DNA Damage, Lung Neoplasms drug therapy, Receptor, IGF Type 1 antagonists & inhibitors, Small Cell Lung Carcinoma drug therapy
- Abstract
Insulin-like growth factor receptor-1 (IGF-1R) inhibition could be a relevant therapeutic approach in small cell lung cancer (SCLC) given the importance of an IGF-1R autocrine loop and its role in DNA damage repair processes. We assessed IGF-1R and pAkt protein expression in 83 SCLC human specimens. The efficacy of R1507 (a monoclonal antibody directed against IGF-1R) alone or combined with cisplatin or ionizing radiation (IR) was evaluated in H69, H146, and H526 cells in vitro and in vivo. Innovative genomic and functional approaches were conducted to analyze the molecular behavior under the different treatment conditions. A total of 53% and 37% of human specimens expressed IGF-1R and pAkt, respectively. R1507 showed single-agent activity in H146 and H526 cells but not in H69 cells. R1507 exhibited synergistic effects with both cisplatin and IR in vitro. The triple combination R1507-cisplatin-IR led to a dramatic delay in tumor growth compared with cisplatin-IR in H526 cells. Analyzing the apparent absence of antitumoral effect of R1507 alone in vivo, we observed a transient reduction of IGF-1R staining intensity in vivo, concomitant to the activation of multiple cell surface receptors and intracellular proteins involved in proliferation, angiogenesis, and survival. Finally, we identified that the nucleotide excision repair pathway was mediated after exposure to R1507-CDDP and R1507-IR in vitro and in vivo. In conclusion, adding R1507 to the current standard cisplatin-IR doublet reveals remarkable chemo- and radiosensitizing effects in selected SCLC models and warrants to be investigated in the clinical setting.
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- 2013
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14. Radiation-induced enteropathy: molecular basis of pentoxifylline-vitamin E anti-fibrotic effect involved TGF-β1 cascade inhibition.
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Hamama S, Gilbert-Sirieix M, Vozenin MC, and Delanian S
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- Adult, Aged, Algorithms, Antioxidants pharmacology, Antioxidants therapeutic use, Blotting, Western, Clinical Trials as Topic, Enzyme-Linked Immunosorbent Assay, Female, Fibrosis drug therapy, Fibrosis etiology, Fibrosis prevention & control, Humans, Immunohistochemistry, Intestinal Diseases etiology, Male, Middle Aged, Pentoxifylline pharmacology, Radiation-Protective Agents pharmacology, Reverse Transcriptase Polymerase Chain Reaction, Treatment Outcome, Vitamin E pharmacology, Intestinal Diseases drug therapy, Intestinal Diseases prevention & control, Pentoxifylline therapeutic use, Radiation-Protective Agents therapeutic use, Radiotherapy adverse effects, Transforming Growth Factor beta1 drug effects, Vitamin E therapeutic use
- Abstract
Background: Radiation-induced fibrosis is a serious late complication of radiotherapy. Pentoxifylline-vitamin E has proven effective and safe in clinical trials in the treatment of fibrosis, while the molecular mechanism of its activity is yet unexplored., Methods: Ten patients suffering from radiation-induced enteropathy were treated with pentoxifylline-vitamin E combination with SOMA score as the primary endpoint. In parallel, primary smooth muscle cells isolated from intestinal samples isolated from humans with radiation enteropathy were incubated with pentoxifylline, trolox (vit. E hydrophilic analogous) or their combination. Activation of the TGF-β1/Smad and Rho/ROCK pathways was subsequently investigated using Q-RT-PCR, gene reporter, Western-blot, ELISA and immunohistochemistry., Results: Pentoxifylline-vitamin E combination induces regression of symptoms (SOMA) by -41% and -80% at 6 and 18months. In vitro, pentoxifylline and trolox synergize to inhibit TGF-β1 protein and mRNA expression. This inhibitory action is mediated at the transcriptional level and leads to subsequent inhibition of TGF-β1/Smad targets (Col Iα1, FN1, PAI-1, CTGF), while it has no effect on the Rho/ROCK pathway., Conclusions: The anti-fibrotic effect of combined pentoxifylline-vitamin E is at least in part mediated by inhibition of the TGF-β1 cascade. It strengthens previous clinical data showing pentoxifylline-vitamin E synergy and supports its use as a first-line treatment of radiation-induced fibrosis., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)
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- 2012
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15. Therapeutic management of intestinal fibrosis induced by radiation therapy: from molecular profiling to new intervention strategies et vice et versa.
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Hamama S, Delanian S, Monceau V, and Vozenin MC
- Abstract
Chronic toxicities of locoregional and systemic oncological treatments commonly develop in long-term cancer survivors. Amongst these toxicities, post-radiotherapeutic complications alter patient's quality of life. Reduction of exposure of normal tissues can be achieved by optimization of radiotherapy. Furthermore, understanding of the fibrogenic mechanisms has provided targets to prevent, mitigate, and reverse late radiation-induced damages. This mini-review shows how (i) global molecular studies using gene profiling can provide tools to develop new intervention strategies and (ii) how successful clinical trials, conducted in particular with combined pentoxifylline-vitamin E, can take benefice of biological and molecular evidences to improve our understanding of fibrogenic mechanisms, enhance the robustness of proposed treatments, and lead ultimately to better treatments for patient's benefice.
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- 2012
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