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Cots E, Casas M, Gregoriano M, Busquet-Dura X, Bielsa J, Chacon C, Kragt L, Torán P, Guinot F. "Ethnic disparities in the prevalence of Molar-Incisor-Hypomineralisation (MIH) and caries among 6-12-year-old children in Catalonia, Spain". Eur J Paediatr Dent 2024; 25:1. [PMID: 38414345 DOI: 10.23804/ejpd.2024.2029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
AIM To study the prevalence of MIH and caries in 6- and 12-year-old schoolchildren and their association with ethnic disparities and other relevant factors. BACKGROUND In recent years, there has been uneven improvement in school children's oral health, highlighting inequalities in access to dental care and health outcomes, particularly among ethnic minorities. The most prevalent oral disease in childhood, caries, is preventable, as its risk factors are well known. However, MIH, a common condition affecting the enamel of permanent incisors and/or molars, has no established aetiology or preventive measures. METHODS A cross-sectional study among schoolchildren was conducted in 725 children from Masnou (Barcelona, 2013) and in 577 children from Sant Andreu de Llavaneres (Barcelona, 2018-2020). Data collection was carried out by means of clinical examination and a selfreferenced questionnaire. Oral health outcomes included: presence of dental caries, presence of MIH, hypomineralised second primary molars (HSPM). All variables were analysed according to ethnic disparities and other variables such as socioeconomics, diet, hygiene habits, plaque and access to dental services. We performed multivariate Poisson regression models with robust variance to examine ethnic disparities in MIH and caries. CONCLUSION This cross-sectional study based in Catalonia, Spain showed that there are ethnic disparities in caries as observed with other child's diseases; however, they do not seem to follow the same pattern for MIH. More studies are needed (i) to explore how MIH behaves among populations in terms of inequality; (ii) to study the aetiological factors of MIH; and (iii) to identify potential factors associated with MIH and caries that have not been studied and that may contribute to the observed ethnic disparities.
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Affiliation(s)
- E Cots
- PhD Student, Department of Paediatric Dentistry, Faculty of Dentistry, Universitat Internacional de Catalunya (UIC), Barcelona, Spain - Professor, Department of Preventive, Community and Public Health Dentistry, Faculty of Dentistry, Universitat Internacional de Catalunya (UIC), Barcelona, Spain - Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain - Multidisciplinary Research Group in Health and Society (GREMSAS) (2021-SGR-0148), 0800711 Barcelona, Spain
| | - M Casas
- ISGlobal, Barcelona, Spain - Universitat Pompeu Fabra (UPF), Barcelona, Spain - Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - M Gregoriano
- Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain
| | - X Busquet-Dura
- Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain - Home Care Program, Granollers Support Team (PADES), Valles Oriental Primary Care Service, Catalan Health Institute, Granollers, Spain
| | - J Bielsa
- Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain
| | - C Chacon
- Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain
| | - L Kragt
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands - Department of Oral & Maxillofacial Surgery, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - P Torán
- Research Support Unit Metropolitana Nord, Primary Care Research Institute Jordi Gol (IDIAPJGol), Mataró, Spain - Multidisciplinary Research Group in Health and Society (GREMSAS) (2021-SGR-0148), 0800711 Barcelona, Spain - Department of Medicine, Faculty of Medicine, Universitat de Girona, 17003 Girona Spain - Primary Care Research Group. Germans Trias i Pujol Research Institute (IGTP), Campus Can Ruti, Badalona, Spain
| | - F Guinot
- Professor and Department Chair, Department of Paediatric Dentistry, Faculty of Dentistry, Universitat Internacional de Catalunya (UIC), Barcelona, Spain
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Parkin C, Kotula P, Podlevsky J, Chacon C, Chiu E, Grutzik S, Rezwan A, Janicki T, Lane JMD, Lim H, Bishop C, Hattar K. Effect of Dopants, Impurities, and Substrate on Anomalous Crystallization of SiN. Microsc Microanal 2023; 29:1470-1471. [PMID: 37613606 DOI: 10.1093/micmic/ozad067.755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Calvin Parkin
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Paul Kotula
- Sandia National Laboratories, Albuquerque, NM, United States
| | | | - Carlos Chacon
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Edwin Chiu
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Scott Grutzik
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Aashique Rezwan
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Tesia Janicki
- Sandia National Laboratories, Albuquerque, NM, United States
| | | | - Hojun Lim
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Chris Bishop
- Sandia National Laboratories, Albuquerque, NM, United States
| | - Khalid Hattar
- Sandia National Laboratories, Albuquerque, NM, United States
- Department of Nuclear Engineering, University of Tennessee-Knoxville, Knoxville, TN, United States
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Chacon C, Suarez M, Karakhanyan V, Desjardin K, Menneglier C, Soppera O, Moutarlier V, Grosjean T. Multipixel x ray detection integrated at the end of a narrow multicore fiber. Opt Lett 2023; 48:2178-2181. [PMID: 37058671 DOI: 10.1364/ol.484887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
We introduce and demonstrate the concept of a multipixel detector integrated at the tip of an individual multicore fiber. A pixel consists here of an aluminum-coated polymer microtip incorporating a scintillating powder. Upon irradiation, the luminescence released by the scintillators is efficiently transferred into the fiber cores owing to the specifically elongated metal-coated tips that ensure efficient luminescence matching to the fiber modes. With each pixel being selectively coupled to one of the cores of the multicore optical fiber, the resulting fiber-integrated x ray detection process is totally free from inter-pixel cross talk. Our approach holds promise for fiber-integrated probes and cameras for remote x and gamma ray analysis and imaging in hard-to-reach environments.
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Ong R, Chacon C, Javier S. Cardiac biomarkers as prognosticators among SARS-CoV-19 patients in a tertiary hospital in Philippines. Eur Heart J 2021. [PMCID: PMC8767625 DOI: 10.1093/eurheartj/ehab724.2494] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background There is overwhelming volume of confirmed cases of COVID-19, despite this numerous knowledge gaps remain in the diagnosis, management, and prognostication of this novel coronavirus infection, making prevention and control a challenge. Methods This retrospective cohort study included patients with real-time reverse transcriptase polymerase chain reaction (rRT-PCR)-confirmed COVID-19. Binary logistic regression was used to determine the association between the cardiac biomarkers and in-hospital mortality. ROC, AUC, and cutoff analyses were used to determine optimal cutoff values for the cardiac biomarkers. Results A total of 90 subjects with a complete panel of cardiac biomarkers out of the 224 rRT-PCR confirmed cases were included. The median age was 57 years (IQR, 47–67 years), majority were males. Sixty-six (77.6%) subjects survived while 19 (22.4%) expired. The most common presenting symptom was fever (75.6%), and the most common comorbidity was hypertension (67.8%). Spearman rho correlation analysis showed moderate positive association of high sensitivity troponin I (hsTnI) with in-hospital mortality (R, 0.434, p = <0.001). Multivariate binary logistic regression analysis showed that creatine kinase and hsTnI were independently associated with in-hospital mortality (OR, 4.103 [95% CI, 1.241–13.563], p=0.021; and OR, 7.899 [95% CI, 2.430–25.675], p=0.001, respectively). ROC curve analysis showed that hsTnI was a good predictor for in-hospital mortality (AUC, 0.829 [95% CI, 0.735–0.923], p = <0.001) and that creatine kinase was a poor predictor (AUC, 0.677 [95% CI, 0.531–0.823], p=0.018). Optimal cutoff point derived from the ROC curve for hsTnI was 0.010 ng/ml (J, 0.574) with a sensitivity of 84% (TPR, 0.842 [95% CI, 0.604–0.966]), specificity of 73% (TNR, 0.732 [95% CI, 0.614–0.386]), and an adjusted negative predictive value of 99% (Known prevalence*adjusted NPV, 0.989), a positive likelihood ratio of 20% (LR+, 3.147 [95% CI, 2.044–4.844]) and a negative likelihood ratio of 30% (LR−, 0.216 [95% CI, 0.076–0.615]). Conclusion High sensitivity troponin I level was a good tool with a very high negative predictive value in significantly predicting in-hospital mortality among rRT-PCR positive COVID-19 patients. Funding Acknowledgement Type of funding sources: None.
ROC Curve ![]() ![]()
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Affiliation(s)
- R Ong
- Makati Medical Center, Department of Medicine, Section of Cardiology, Makati, Philippines
| | - C Chacon
- Makati Medical Center, Department of Medicine, Section of Cardiology, Makati, Philippines
| | - S Javier
- Makati Medical Center, Department of Medicine, Section of Cardiology, Makati, Philippines
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Tettamanti ME, Gimenez I, Chacon C, Nadal J, Costanzo V, Nervo A, Losco F, Chacon R, Santos DA. Sensitivity and specificity of strain rate for the early detection of left ventricular dysfunction in breast cancer patients receiving adjuvant treatment with adriamycin with or without trastuzumab. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2857] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Medical literature states that a global longitudinal strain rate (GLS) <−19% and further reductions in relation with baseline GLS may predict long term left ventricular dysfunction in breast cancer patients receiving adjuvant treatment with Adriamycin (A) with or without trastuzumab (T). However, there is not strong evidence to support the use of this technique in daily clinical practice.
Purpose
To analyze the sensitivity (S) and specificity (Sp) of GLS <−19% or its relative 10, 15 and 20% reduction form baseline, for the early detection of left ventricular dysfunction in breast cancer patients receiving adjuvant treatment with A with or without T.
Methods
Patients were prospectively assessed with a cardiac echoDoppler + GLS at baseline, every 3 months during the first year and every 4 months thereafter. We assessed the S and Sp of GLS <−19% or its relative >10%, >15% and >20% reduction form baseline after treatment with A with or without T as predictors of cardiotoxicity (defined as a >10 percentage points decrease of left ventricular ejection fraction to a value below the lower normal limit with respect to baseline).
Results
136 out of 884 patients (16%) had GLS measured at each visit: 83 patients (60%) and 53 patients (40%) treated with A or A+T respectively. Patients were followed up to 31±6 months. Mean age was 51±12 years. The table shows the baseline characteristics of both groups. 10 out of 83 patients in group A (12%) and 18 out of 53 P in group A+T (34%) developed cardiotoxicity. Baseline left ventricular ejection fraction and GLS were 61±4,7% and −20,18±2,6% in group A, and 58,7±5,8% and −19,5±2,6 post treatment. In this group, GLS S and Sp were 50 and 80%, respectively. In the group A+T, the best GLS cutoff was −19%, with a 60% sensitivity and 78% specificity.
Conclusions
In our non-selected cohort of patients, nor GLS or its percentage reductions along follow up predicted the reduction of left ventricular ejection fraction and the developing of cardiotoxic ventricular dysfunction in breast cancer patients receiving adjuvant treatment with A with or without T. The systematic use of this tool should be further investigated and validated at each center to help establish its usefulness in daily practice.
Funding Acknowledgement
Type of funding sources: None. Baseline characteristics
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Affiliation(s)
- M E Tettamanti
- Alexander Fleming Institute, Cardio Oncology, Buenos Aires, Argentina
| | - I Gimenez
- Alexander Fleming Institute, Cardio Oncology, Buenos Aires, Argentina
| | - C Chacon
- Alexander Fleming Institute, Radiotherapy, Buenos Aires, Argentina
| | - J Nadal
- Alexander Fleming Institute, Oncology, Buenos Aires, Argentina
| | - V Costanzo
- Alexander Fleming Institute, Oncology, Buenos Aires, Argentina
| | - A Nervo
- Alexander Fleming Institute, Oncology, Buenos Aires, Argentina
| | - F Losco
- Alexander Fleming Institute, Oncology, Buenos Aires, Argentina
| | - R Chacon
- Alexander Fleming Institute, Oncology, Buenos Aires, Argentina
| | - D A Santos
- Alexander Fleming Institute, Cardio Oncology, Buenos Aires, Argentina
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Melendez P, McDaniel K, Chacon C, Poock S, Bartolome J, Pinedo P. Association between blood β-hydroxybutyrate at 7 days postpartum and milk yield, disease occurrence and fertility in grazing dairy cattle with seasonal calving: a case study. Anim Prod Sci 2020. [DOI: 10.1071/an19414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context
Ketosis in grazing cattle has been sparsely studied. A large commercial grazing dairy in southern Chile, representative of a significant proportion of the systems in the country, was used in this case study.
Aims
The study had three objectives: (i) to establish a cut-off for β-hydroxybutyrate (BHB) concentration for subclinical ketosis (SCK), and use this to measure the proportion of cows with SCK at 7 days postpartum in spring- and autumn-calving cows; (ii) to describe the relationship of SCK and other periparturient diseases and fertility; and (iii) to compare milk yield of healthy cows and those affected by SCK in a dairy herd with autumn and spring parturitions under grazing conditions in southern Chile.
Methods
During 2016, 234 cows with autumn parturitions and 632 cows with spring parturitions (n = 866) were assessed for blood BHB at 7 days postpartum. A receiver operating characteristic analysis for a BHB cut-off value was completed. Models were developed for disease occurrence, culling risk, conception risk and pregnancy rate, considering SCK as the main explanatory variable.
Key results
In total, 810 cows were used for the final analysis. The frequency of cows with SCK, based on the cut-off value obtained (BHB ≥1.1 mmol/L), was 22.2% at 7 days postpartum. The risk of SCK was higher (P < 0.0001) in cows calving in spring (27.0%) than in autumn (10.3%), and in multiparous (24.6%) than primiparous cows (15.1%). The seasonal difference in proportion of cows with SCK was parity-dependent, because the frequency of SCK in multiparous cows was higher (P < 0.0005) in spring (32.0%) than autumn (10.1%), whereas SCK in primiparous cows showed no significant (P = 0.41) difference between spring (15.4%) and autumn (12.5%). Milk production up to 100 days-in-milk was greater (P = 0.002) in cows with SCK (3394 kg) than without SCK (3015 kg). Disease occurrence was higher (P < 0.0001) in cows with SCK and in multiparous cows (P < 0.0001). There was no difference in conception risk at first service (P = 0.62) or in overall pregnancy rate (P = 0.90) between cows with and without SCK.
Conclusions
Multiparous cows calving in spring had the highest risk of SCK (BHB ≥1.1 mmol/L). SCK was associated with higher milk yield and greater occurrence of other diseases, but not with reproductive performance.
Implications
Grazing herds have challenges with SCK that may require different management strategies depending on the calving season and the parity of the animals.
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SanMartin CD, Henriquez M, Chacon C, Ponce DP, Salech F, Rogers NK, Behrens MI. Vitamin D Increases Aβ140 Plasma Levels and Protects Lymphocytes from Oxidative Death in Mild Cognitive Impairment Patients. Curr Alzheimer Res 2019; 15:561-569. [PMID: 29283046 DOI: 10.2174/1567205015666171227154636] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [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: 07/11/2017] [Accepted: 12/18/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Mild cognitive impairment (MCI) has an increased rate of progression to dementia. Alterations of some metabolic factors, such as deficiency of vitamin D, are a risk factor for cognitive deterioration. Vitamin D is involved in the clearance of β-amyloid (Aβ) from the brain. We have reported that lymphocytes from Alzheimer's disease (AD) patients have an increased susceptibility to oxidative death by H2O2 exposure, but currently it is unknown if this characteristic is modifiable in vivo. OBJECTIVE To determine if correction of low vitamin D levels protects lymphocytes from oxidative death and increases Aβ1-40 plasma levels in MCI and very early AD (VEAD) patients. METHOD Sixteen MCI, 11 VEAD and 25 healthy control (HC) voluntaries were evaluated with the Clinical Dementia Rating (CDR), Montreal Cognitive assessment (MoCA), and Memory Index score (MIS). Lymphocyte death was measured by flow cytometry after 20h exposure to H2O2. In patients with low levels of vitamin D -11 MCI, 9 VEAD and 20 HC- lymphocyte H2O2-death, plasma Aβ1-40 levels and cognitive status were evaluated pre- and post-vitamin D supplementation for 6 months. RESULTS Lymphocytes from MCI and VEAD patients showed increased susceptibility to oxidative death at study entry. In MCI, but not VEAD patients, lymphocyte susceptibility to death and Aβ1-40 levels plasma levels improved after 6 months of vitamin D supplementation. In addition, cognitive status on follow-up (18 months) improved in MCI patients after vitamin D supplementation. CONCLUSION Vitamin D supplementation may be beneficial in MCI. The lack of effect in VEAD may be due to a more advanced stage or different characteristics of the neurodegenerative process.
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Affiliation(s)
- Carol D SanMartin
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile,Center for Integrative Biology, Universidad Mayor, Santiago, Chile
| | - Mauricio Henriquez
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad
de Chile, Santiago, Chile
| | - Carlos Chacon
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad
de Chile, Santiago, Chile
| | - Daniela P Ponce
- Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de
Chile, Santiago, Chile
| | - Felipe Salech
- Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de
Chile, Santiago, Chile,Unidad de Geriatría, Departamento de Medicina Interna, Santiago, Chile,Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Nicole K Rogers
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile,Instituto de Neurocirugía, Dr Asenjo,
Santiago, Chile
| | - Maria I Behrens
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile,Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de
Chile, Santiago, Chile,Unidad de Geriatría, Departamento de Medicina Interna, Santiago, Chile,Clínica de Alemana, Santiago. Chile
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Urzua U, Chacon C, Lizama L, Sarmiento S, Villalobos P, Kroxato B, Marcelain K, Gonzalez MJ. Parity History Determines a Systemic Inflammatory Response to Spread of Ovarian Cancer in Naturally Aged Mice. Aging Dis 2017; 8:546-557. [PMID: 28966800 PMCID: PMC5614320 DOI: 10.14336/ad.2017.0110] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 01/10/2017] [Indexed: 01/09/2023] Open
Abstract
Aging intersects with reproductive senescence in women by promoting a systemic low-grade chronic inflammation that predisposes women to several diseases including ovarian cancer (OC). OC risk at menopause is significantly modified by parity records during prior fertile life. To date, the combined effects of age and parity on the systemic inflammation markers that are particularly relevant to OC initiation and progression at menopause remain largely unknown. Herein, we profiled a panel of circulating cytokines in multiparous versus virgin C57BL/6 female mice at peri-estropausal age and investigated how cytokine levels were modulated by intraperitoneal tumor induction in a syngeneic immunocompetent OC mouse model. Serum FSH, LH and TSH levels increased with age in both groups while prolactin (PRL) was lower in multiparous respect to virgin mice, a finding previously observed in parous women. Serum CCL2, IL-10, IL-5, IL-4, TNF-α, IL1-β and IL-12p70 levels increased with age irrespective of parity status, but were specifically reduced following OC tumor induction only in multiparous mice. Animals developed hemorrhagic ascites and tumor implants in the omental fat band and other intraperitoneal organs by 12 weeks after induction, with multiparous mice showing a significantly extended survival. We conclude that previous parity history counteracts aging-associated systemic inflammation possibly by reducing the immunosuppression that typically allows tumor spread. Results suggest a partial impairment of the M2 shift in tumor-associated macrophages as well as decreased stimulation of regulatory B-cells in aged mice. This long term, tumor-concurrent effect of parity on inflammation markers at menopause would be a contributing factor leading to decreased OC risk.
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Affiliation(s)
- Ulises Urzua
- 1Laboratorio de Genómica Aplicada, Facultad de Medicina, Universidad de Chile.,4Programa de Biología Celular y Molecular, ICBM.,5Departamento de Oncología Básica y Clínica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Carlos Chacon
- 1Laboratorio de Genómica Aplicada, Facultad de Medicina, Universidad de Chile
| | | | - Sebastián Sarmiento
- 1Laboratorio de Genómica Aplicada, Facultad de Medicina, Universidad de Chile
| | - Pía Villalobos
- 1Laboratorio de Genómica Aplicada, Facultad de Medicina, Universidad de Chile
| | - Belén Kroxato
- 1Laboratorio de Genómica Aplicada, Facultad de Medicina, Universidad de Chile
| | - Katherine Marcelain
- 3Programa de Genética Humana, ICBM.,5Departamento de Oncología Básica y Clínica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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Hodar C, Zuñiga A, Pulgar R, Travisany D, Chacon C, Pino M, Maass A, Cambiazo V. Comparative gene expression analysis of Dtg, a novel target gene of Dpp signaling pathway in the early Drosophila melanogaster embryo. Gene 2013; 535:210-7. [PMID: 24321690 DOI: 10.1016/j.gene.2013.11.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/30/2013] [Accepted: 11/14/2013] [Indexed: 10/25/2022]
Abstract
In the early Drosophila melanogaster embryo, Dpp, a secreted molecule that belongs to the TGF-β superfamily of growth factors, activates a set of downstream genes to subdivide the dorsal region into amnioserosa and dorsal epidermis. Here, we examined the expression pattern and transcriptional regulation of Dtg, a new target gene of Dpp signaling pathway that is required for proper amnioserosa differentiation. We showed that the expression of Dtg was controlled by Dpp and characterized a 524-bp enhancer that mediated expression in the dorsal midline, as well as, in the differentiated amnioserosa in transgenic reporter embryos. This enhancer contained a highly conserved region of 48-bp in which bioinformatic predictions and in vitro assays identified three Mad binding motifs. Mutational analysis revealed that these three motifs were necessary for proper expression of a reporter gene in transgenic embryos, suggesting that short and highly conserved genomic sequences may be indicative of functional regulatory regions in D. melanogaster genes. Dtg orthologs were not detected in basal lineages of Dipterans, which unlike D. melanogaster develop two extra-embryonic membranes, amnion and serosa, nevertheless Dtg orthologs were identified in the transcriptome of Musca domestica, in which dorsal ectoderm patterning leads to the formation of a single extra-embryonic membrane. These results suggest that Dtg was recruited as a new component of the network that controls dorsal ectoderm patterning in the lineage leading to higher Cyclorrhaphan flies, such as D. melanogaster and M. domestica.
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Affiliation(s)
- Christian Hodar
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile
| | - Alejandro Zuñiga
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile
| | - Rodrigo Pulgar
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile
| | - Dante Travisany
- Laboratorio de Bioinformática y Matemática del Genoma, Center for Mathematical Modeling, FCFM-Universidad de Chile, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile
| | - Carlos Chacon
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile
| | - Michael Pino
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile
| | - Alejandro Maass
- Laboratorio de Bioinformática y Matemática del Genoma, Center for Mathematical Modeling, FCFM-Universidad de Chile, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile; Department of Mathematical Engineering, FCFM-Universidad de Chile, Santiago, Chile
| | - Verónica Cambiazo
- Laboratorio de Bioinformática y Expresión Génica, INTA-Universidad de Chile, El Líbano 5524, Santiago, Chile; Fondap Center for Genome Regulation (CGR), Universidad de Chile, Santiago, Chile.
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Breitwieser R, Marsault M, Repain V, Lagoute J, Chacon C, Girard Y, Rousset S, Qin Z, Battaglini N, Zrig S, Lang P. Long-range ordered nanodomains of grafted electroactive molecules. J Chem Phys 2013; 139:204703. [PMID: 24289365 DOI: 10.1063/1.4830402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We demonstrate the capability to build zero and one-dimensional electroactive molecular nanostructures ordered over a macroscopic scale and stable under ambient conditions. To realize these arrays, we use the selective grafting of functionalized thiols (juglon and terthiophene based) on a self-organized metallic template. The nanoscale patterning of the molecular conductance is demonstrated and analyzed by scanning tunneling spectroscopy. Finally, the influence of the nanostructuring on electro-chemical properties is measured, paving the way to an all-bottom-up fabrication of nanostructured templates for nanosciences.
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Affiliation(s)
- R Breitwieser
- MPQ, Université Paris Diderot-Paris 7, Sorbonne Paris Cité, CNRS, UMR 7162, 10 rue A. Domon et L. Duquet, 75205 Paris 13, France
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Orlandini A, Castellana N, Pascual A, Botto F, Bahit C, Chacon C, Diaz R. Usefulness of myocardial viability tests in the decision making process to indicate revascularization in patients with left ventricular dysfunction and coronary artery disease. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p5749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Battaglini N, Qin Z, Campiglio P, Repain V, Chacon C, Rousset S, Lang P. Directed growth of mixed self-assembled monolayers on a nanostructured template: a step toward the patterning of functional molecular domains. Langmuir 2012; 28:15095-15105. [PMID: 23016599 DOI: 10.1021/la302943t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report on the elaboration of networks of SAM domains. More precisely, we show the feasibility in making arrays of functionalized alkylthiol nanodomains bordered with an alkylthiol matrix. The several step process relies on the replication of a self-organized cobalt array grown on Au(111). The SAM process takes place in solution. The chemical affinity of thiol for gold leads to the selective grafting of molecules on the surface. After having removed the inorganic array, alkylthiol functionalized with a terthiophene unit is grafted in free gold areas. The efficiency of the replication of the initial template depends on the stability of the first SAM. We also investigate electronic tunnel transport through oligothiophene islands with the STM. The variation of the molecular contrast with bias voltage between the two molecular species indicates a potential resonant tunneling mechanism through the orbitals of the aromatic compound.
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Affiliation(s)
- N Battaglini
- University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS, Paris, France.
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Kawahara SL, Lagoute J, Repain V, Chacon C, Girard Y, Rousset S, Smogunov A, Barreteau C. Large magnetoresistance through a single molecule due to a spin-split hybridized orbital. Nano Lett 2012; 12:4558-4563. [PMID: 22827486 DOI: 10.1021/nl301802e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Using organic materials in spintronic devices raises a lot of expectation for future applications due to their flexibility, low cost, long spin lifetime, and easy functionalization. However, the interfacial hybridization and spin polarization between the organic layer and the ferromagnetic electrodes still has to be understood at the molecular scale. Coupling state-of-the-art spin-polarized scanning tunneling spectroscopy and spin-resolved ab initio calculations, we give the first experimental evidence of the spin splitting of a molecular orbital on a single non magnetic C(60) molecule in contact with a magnetic material, namely, the Cr(001) surface. This hybridized molecular state is responsible for an inversion of sign of the tunneling magnetoresistance depending on energy. This result opens the way to spin filtering through molecular orbitals.
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Affiliation(s)
- S L Kawahara
- Laboratoire Matériaux et Phénomènes Quantiques, UMR7162, Université Paris Diderot, Paris 7, Sorbonne Paris Cité, CNRS, UMR 7162 case courrier 7021, 75205 Paris 13, France
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Lagoute J, Kawahara SL, Chacon C, Repain V, Girard Y, Rousset S. Spin-polarized scanning tunneling microscopy and spectroscopy study of chromium on a Cr(001) surface. J Phys Condens Matter 2011; 23:045007. [PMID: 21406881 DOI: 10.1088/0953-8984/23/4/045007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Several tens of chromium layers were deposited at 250 °C on a Cr(001) surface and investigated by spin-polarized scanning tunneling microscopy (SP-STM), Auger electron spectroscopy (AES) and scanning tunneling spectroscopy (STS). Chromium is found to grow with a mound-like morphology resulting from the stacking of several monolayers which do not uniformly cover the whole surface of the substrate. The terminal plane consists of an irregular array of Cr islands with lateral sizes smaller than 20 × 20 nm(2). Combined AES and STS measurements reveal the presence of a significant amount of segregants prior to and after deposition. A detailed investigation of the surface shows that it consists of two types of patches. Thanks to STS measurements, the two types of area have been identified as being either chromium pure or segregant rich. SP-STM experiments have evidenced that the antiferromagnetic layer coupling remains in the chromium mounds after deposition and is not significantly affected by the presence of the segregants.
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Affiliation(s)
- J Lagoute
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot et CNRS, UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France.
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Mehendale S, Girard Y, Repain V, Chacon C, Lagoute J, Rousset S, Marathe M, Narasimhan S. Ordered surface alloy of bulk-immiscible components stabilized by magnetism. Phys Rev Lett 2010; 105:056101. [PMID: 20867936 DOI: 10.1103/physrevlett.105.056101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Indexed: 05/29/2023]
Abstract
Using scanning tunneling microscopy and a diffraction experiment, we have discovered a new ordered surface alloy made out of two bulk-immiscible components, Fe and Au, deposited on a Ru(0001) substrate. In such a system, substrate-mediated strain interactions are believed to provide the main driving force for mixing. However, spin-polarized ab initio calculations show that the most stable structures are always the ones with the highest magnetic moment per Fe atom and not the ones minimizing the surface stress, in remarkable agreement with the observations. This opens up novel possibilities for creating materials with unique properties of relevance to device applications.
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Affiliation(s)
- S Mehendale
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot-Paris 7, UMR CNRS 7162, 75205 Paris Cedex 13, France
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Rohart S, Campiglio P, Repain V, Nahas Y, Chacon C, Girard Y, Lagoute J, Thiaville A, Rousset S. Spin-wave-assisted thermal reversal of epitaxial perpendicular magnetic nanodots. Phys Rev Lett 2010; 104:137202. [PMID: 20481908 DOI: 10.1103/physrevlett.104.137202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Indexed: 05/29/2023]
Abstract
The magnetic susceptibility of self-organized two-dimensional Co nanodots on Au(111) has been measured as a function of their size in the 2-7 nm diameter range. We show that the activation energy for the thermal reversal displays a power law behavior with the dot volume. Atomic scale simulations based on the Heisenberg Hamiltonian show that this behavior is due to a deviation from the macrospin model for dot size as small as 3 nm in diameter. This discrepancy is attributed to finite temperature effects through the thermal excitation of spin-wave modes inside the particles.
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Affiliation(s)
- S Rohart
- Laboratoire de Physique des Solides, CNRS, Université Paris Sud, UMR 8502, Bâtiment 510, F-91405 Orsay Cedex, France.
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Lin H, Lagoute J, Repain V, Chacon C, Girard Y, Lauret JS, Ducastelle F, Loiseau A, Rousset S. Many-body effects in electronic bandgaps of carbon nanotubes measured by scanning tunnelling spectroscopy. Nat Mater 2010; 9:235-238. [PMID: 20081833 DOI: 10.1038/nmat2624] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 12/18/2009] [Indexed: 05/28/2023]
Abstract
Single-walled carbon nanotubes provide an ideal system for studying the properties of one-dimensional (1D) materials, where strong electron-electron interactions are expected. Optical measurements have recently reported the existence of excitons in semiconducting nanotubes, revealing the importance of many-body effects. Surprisingly, pioneering electronic structure calculations and scanning tunnelling spectroscopy (STS) experiments report the same gap values as optical experiments. Here, an experimental STS study of the bandgap of single-walled semiconducting nanotubes, demonstrates a continuous transition from the gap reduced by the screening resulting from the metal substrate to the intrinsic gap dominated by many-body interactions. These results provide a deeper knowledge of many-body interactions in these 1D systems and a better understanding of their electronic properties, which is a prerequisite for any application of nanotubes in the ultimate device miniaturization for molecular electronics, or spintronics.
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Nahas Y, Repain V, Chacon C, Girard Y, Lagoute J, Rodary G, Klein J, Rousset S, Bulou H, Goyhenex C. Dominant role of the epitaxial strain in the magnetism of core-shell Co/Au self-organized nanodots. Phys Rev Lett 2009; 103:067202. [PMID: 19792607 DOI: 10.1103/physrevlett.103.067202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Indexed: 05/28/2023]
Abstract
Self-organized Co nanodots on a Au(111) surface have been surrounded by controlled Au rings that progressively cap the entire dots. The magnetic susceptibility of these dots has been measured in situ as a function of the Au coverage. The blocking temperature increases when the Co bilayer dots are surrounded by the first Au atomic layer and decreases with the subsequent capping. This result cannot be explained by interfacial anisotropy which is generally assumed to be the dominant term in the magnetic anisotropy of nanostructures. Using molecular dynamics simulations, we evidence that the large strain inside the Co clusters is the main driving force for the anisotropy changes during the Au encapsulation.
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Affiliation(s)
- Y Nahas
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris-Diderot Paris 7, UMR CNRS 7162, 75205 Paris Cedex 13, France
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Carrizo MN, Sade JP, Costanzo MV, Chacon M, Chacon C, Orlando M, Chacon RD. Combined modality treatment for organ preservation in patients with invasive bladder cancer. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e16129] [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
e16129 Purpose: To evaluate long term results of chemoradiation and organ preservation in invasive T2-T4a bladder carcinoma in a single institution with prolonged follow up. Methods: Sixty one patients with clinical stage II and III (T3N0) muscle invasive bladder carcinoma were treated between February 1991 and December 2007. Forty four received sequential treatment (chemo followed by radiation) and seventeen concurrent treatments. Chemotherapy was platinum based in all patients, fifth teen with Carboplatin. All underwent maximal citoreduction with TUR .First 20 patients received pelvic radiation (1991–1993),while the other 41 three-dimensional radiotherapy (median dose 60 Gy). Male/female 55/6: median age 64 (range 46–80); transitional type 58 and mixed-epidermoid 6. Grade II: 3, grade III: 48 and grade IV: 10. Clinical stage II:50 and III:11. Mean follow up 63 months. Results: The 5 year overall survival rate was 57%. Forty patients remained NED, with eight deaths due to second primary or cardiovascular disease. Twenty pts were treated more than 5 years ago, 16(80%) are alive, 14 NED,2 pts relapsed after 5 years. Of all predictive factors analyzed only clinical stage reached statistical significance for relapse (p=0.0029), and borderline significance for overall survival (p=0.064). Toxicity: Grade 3–4: 7%, with 3% of febrile neutropenia. No patient required cystectomy because of bladder morbidity. Conclusions: Trimodality treatment in selected patients offers rates of event free survival and overall survival similar to those reported for surgery with acceptable toxicity and no treatment related cystectomy. Relapse after 5 year is very uncommon. In this small group of patient results were similar with concurrent and sequential treatment. At present we treat our patients with concurrent chemoradiation with tridimensional technique. No significant financial relationships to disclose.
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Affiliation(s)
- M. N. Carrizo
- Instituto Alexander Fleming, Buenos Aires, Argentina
| | - J. P. Sade
- Instituto Alexander Fleming, Buenos Aires, Argentina
| | | | - M. Chacon
- Instituto Alexander Fleming, Buenos Aires, Argentina
| | - C. Chacon
- Instituto Alexander Fleming, Buenos Aires, Argentina
| | - M. Orlando
- Instituto Alexander Fleming, Buenos Aires, Argentina
| | - R. D. Chacon
- Instituto Alexander Fleming, Buenos Aires, Argentina
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Chacon M, Varela M, Huertas E, Roca E, Sanchez Loria F, Kaplan J, Pairola A, O’Connor J, Chacon C, Chacon RD. Surgical salvage of pelvic recurrences from colorectal tumors. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13580] [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
13580 Background: The morbidity of pelvic recurrences from colorectal tumors (PRCT) represents a challenge for the oncology multidisciplinary team. Surgical treatment is the best option for palliation and in several series it offers long term local control in 30% of the cases. Objective: To perform a retrospective analysis of patients (pts) surgically resected for PRCT in terms of: time to progression after surgical salvage (TP) and specific suvival (SS). Correlatives studies were performed with clinic and pathologic factors, surgical procedures (SP), and postoperative complications in terms of TP and SS. Methods: 64 pts treated (June 1994 - February 2005) were identified (women: 30), median age 63 years, site of the primary: rectum 48, sigmoid 16; Median number of resected nodes: 8 (r: 2 - 20) in pts with negative nodes and 15 (r: 6 - 42) in pts with positive nodes; primary treatment: surgery (S): 22 pts, S + chemotherapy (CT): 18, S + radiotherapy (RT): 4, S + CT/RT: 17, CT + S: 2 pts, QT/RT + CX: 1; in 7/64 a Miles procedure was performed as primary therapy, median disease free interval: 15 months; site of initial recurrence: locoregional 58 (90%), locoregional + systemic 10%. Pain and bleeding were the most frecuent symptoms. Results: The strategy in PRCT was: S: 29 pts, S + RT: 15, S + CT/RT: 9, CT/RT + S: 7, S + CT: 2, CT + S: 1, RT + S:1; IORT: 18/64; external beam RT: 17/64, 6 pts required Miles; type of resection: R0: 50/64 (78%), R1: 8/64 (12%), R2: 3/64 (5%) and 3 (5%) unknown. Median duration of surgery: 4 hours, abscesses and fistulas were the complications most frequently observed. Median time to progression (TP): 12 months, site of recurrence (56/64 pts) post salvage surgery: pelvic: 22 pts, extrapelvic: 6 pts, combined: 10 and unknown 18. Eleven pts are free of disease. In 16 pts more than one surgical salvage was perfomed. The specific survival was 21 months (IC 95% 37 - 61 m). Conclusions: In this serie surgical salvage of PRCT showed one year of local control disease, even in pts with R2 and with moderate morbidity. The surgical decision must be individualized and in the context of a trained surgical team. No significant financial relationships to disclose.
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Affiliation(s)
- M. Chacon
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - M. Varela
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - E. Huertas
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - E. Roca
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - F. Sanchez Loria
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - J. Kaplan
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - A. Pairola
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - J. O’Connor
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - C. Chacon
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
| | - R. D. Chacon
- Fleming, Buenos Aires, Argentina; Instituto Alexander Fleming, Buenos Aires, Argentina
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Abstract
A psychiatric population of 94 inpatients and 12 outpatients was investigated on referral to a psychiatric unit in a general hospital for serum antibody titres to several viruses by a complement fixation technique. Of the total population studied, only eight were considered to have antibody titres of possible significance. This result would appear to indicate that viral infection does not play a major part in the causation or precipitation of psychiatric disorders.
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