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BACKGROUND: To examine clinical and sociodemographic differences between patients with delusional disorder; with and without diagnoses of an additional severe mental disorder (SMD) or cognitive impairment. METHODS: Population-based study including all individuals diagnosed with DD between 2005 and 2021 from a large catchment area in Madrid, Spain. Sociodemographic and clinical characteristics and the antipsychotic prescription patterns of the study population was described. Patients were divided into (i) patients with DD and no additional diagnosis of SMD or cognitive impairment (DD group), (ii) patients with DD and a diagnosis of an additional SMD (DD-SMD group), and (iii) patients with DD and cognitive impairment (DD-CI group). RESULTS: Of 1109 patients with a DD diagnosis (62.5 % female), 131 (11.8 %) patients were diagnosed with an additional SMD, and 69 (6.2 %) were diagnosed with cognitive impairment. DD-SMD patients were on average 10 years younger and had longer time between first mental healthcare contact and DD disorder than DD patients. DD-CI patients were on average 10 years older and had a higher proportion of females. Paliperidone (21.9 %) and aripiprazole (20.6 %) were the modal antipsychotic drugs chosen overall. DD-SMD patients were more likely to receive paliperidone and to be prescribed long-acting injectable medication; DD-CI were more likely to receive risperidone or quetiapine; and DD patients were more likely to receive olanzapine. CONCLUSIONS: Sociodemographic and clinical characteristics and choice of antipsychotic drug and delivery method for individuals with DD vary based on its comorbidity.
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OBJECTIVE: The objective of this study was to identify factors associated with long-term opioid use and to assess the association between long-term use and death. STUDY DESIGN: Retrospective cohort study combining several population-wide databases and covering a population of five million inhabitants, including all adults who were initiated on opioid treatment from 2014 to 2018 for non-cancer pain. METHODS: We used logistic regression models to identify factors associated with chronic opioid use and carried out survival analyses using multivariable Cox regression modelling for all-cause mortality during follow-up using inverse probability of treatment weighting (IPTW) and propensity scores based on the probability of using opioids chronically. RESULTS: Among 760,006 patients, 82,423 (10.85%) used opioids for 90 days or more after initiation. Initial therapy characteristics associated with higher risk for long-term use were initiating with long- and short-acting opioids (when compared to tramadol, odds ratio [OR]: 2.63, 95% confidence interval [CI]: 2.57, 2.69 and OR: 1.60, 95%CI: 1.46, 1.76, respectively), using higher daily doses (when compared to 50 morphine milligramme equivalent [MME] or less, prescribing 50 to 89 daily MME, OR: 1.76, 95%CI: 1.65, 1.87; 90 to 119 daily MME, OR: 2.44, 95%CI: 1.99, 3.01; and more than 120 daily MME, OR: 1.77, 95%CI: 1.64, 1.91), and overlapping with gabapentinoids (OR: 2.26, 95%CI: 2.20, 2.32), benzodiazepines (OR: 1.32, 95%CI: 1.30, 1.35), and antipsychotics (OR: 1.21, 95%CI: 1.16, 1.26). After IPTW, chronic opioid use was associated with higher risk of all-cause mortality when compared to short-term use (Hazard Ratio (HR): 1.37, 95%CI: 1.32, 1.42). Sensitivity analyses provided similar results. CONCLUSION: These findings may help healthcare managers to identify and address patients at higher risk of long-term use and riskier prescription patterns.
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Analgésicos Opioides , Humanos , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Adulto , Pontuação de Propensão , Dor Crônica/tratamento farmacológico , Idoso de 80 Anos ou maisRESUMO
Although the pour plate method is widely employed in microbiological quality control, it has certain drawbacks, including having to melt the culture medium before seeding. In this study, the preparation of the culture medium was modified by using a lower concentration of agar (10 g/L), which was separated from the nutrients during sterilization. The new protocol was assessed in media frequently used in microbiological quality control of food, cosmetics, and pharmaceutical products, with tryptic soy agar (TSA), Sabouraud 4% dextrose agar (SDA), and violet red bile glucose agar (VRBG). In comparison with the conventionally produced media, the modifications significantly improved the growth of Saccharomyces cerevisiae in SDA, Staphylococcus aureus, Salmonella enterica subsp. enterica serovar Typhimurium, and Candida albicans in TSA and Escherichia coli ATCC 8739 and ATCC 25922 and S. Typhimurium in VRBG. The modified VRBG was also more selective for Pseudomonas aeruginosa. Regarding physicochemical properties, a significantly lower pH was observed in TSA and VRBG and lower strength values in TSA. Sterilizing agar separately from the other components of the medium and reducing the agar concentration to 10 g/L can improve microorganism growth and enhance the selectivity of differential media in the pour plate method. These modifications could facilitate the automation of this culture technique. IMPORTANCE In the era of rapid microbiological methods, there is a need to improve long-established culture techniques. Drawbacks of the pour plate method include having to melt each medium separately before seeding. For this technique, we demonstrate that separating the agar from the other components of commonly used media during sterilization and reducing the agar concentration to 10 g/L can enhance microbial growth. The new protocol could have advantages in routine laboratory practice because less agar is required and the same molten agar suspension can be used to prepare different media. Moreover, these modifications could facilitate the automation of the pour plate method.
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Técnicas Microbiológicas , Salmonella typhimurium , Ágar , Meios de Cultura , Escherichia coli , EsterilizaçãoRESUMO
The detection of Salmonella in food is based on the use of a selective enrichment broth such as Muller-Kauffman Tetrathionate-Novobiocin (MKTTn), in which tetrathionate plays a key role by providing Salmonella with a growth advantage. As sodium tetrathionate is unstable, it is generated in situ by the addition of iodine (Lugol's solution) before seeding. This step is cumbersome as the solution is easily spilled, compromising the performance of the medium and hindering the work of technicians. The aim of this study was to optimize MKTTn broth by generating tetrathionate ex situ through an external reaction between iodine and thiosulphate followed by lyophilization. Quality control procedures were performed to compare the modified and original media, testing pure productivity (enrichment with 50-120 CFU of Salmonella Thyphimurium ATCC 14028 and Salmonella Enteritidis ATCC 13076 and plating on Xylose Lysine Deoxycholate agar, XLD), mixed productivity (50-120 CFU of Salmonella strains and Pseudomonas aeruginosa and Escherichia coli at ≥104 CFU and XLD plating) and selectivity (≥104 CFU of P. aeruginosa and Enterococcus faecalis and plating on Tryptone Casein Soy agar, TSA). The modified MKTTn medium (S/L) performed comparably with the original medium in terms of growth of both Salmonella strains (>300 colonies in XLD), alone or with P. aeruginosa and E. coli. Quantitative assays showed no statistically significant differences in the number of colonies grown on XLD after 10-5 dilution (p = 0.7015 with S. Thyphimurium ATCC 14028 and p = 0.2387 with S. Enteritidis ATCC 13076; ANOVA test). MKTTn medium (S/L) was also selective against E. coli (≤100 colonies) and E. faecalis (<10 colonies). These results suggest that adding tetrathionate as a lyophilisate (S/L) is a feasible alternative to the use of Lugol's solution for the preparation of MKTTn enrichment broth and does not affect the properties of the medium.
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Iodo , Salmonella enterica , Ágar , Meios de Cultura , Escherichia coli , Novobiocina , Salmonella enteritidisRESUMO
Oxidation of H3 at lysine 4 (H3K4ox) by lysyl oxidase-like 2 (LOXL2) generates an H3 modification with an unknown physiological function. We find that LOXL2 and H3K4ox are higher in triple-negative breast cancer (TNBC) cell lines and patient-derived xenografts (PDXs) than those from other breast cancer subtypes. ChIP-seq revealed that H3K4ox is located primarily in heterochromatin, where it is involved in chromatin compaction. Knocking down LOXL2 reduces H3K4ox levels and causes chromatin decompaction, resulting in a sustained activation of the DNA damage response (DDR) and increased susceptibility to anticancer agents. This critical role that LOXL2 and oxidized H3 play in chromatin compaction and DDR suggests that functionally targeting LOXL2 could be a way to sensitize TNBC cells to conventional therapy.
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Aminoácido Oxirredutases/genética , Cromatina/genética , Código das Histonas/genética , Neoplasias de Mama Triplo Negativas/genética , Animais , Linhagem Celular Tumoral , Dano ao DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Heterocromatina/genética , Xenoenxertos , Histonas/genética , Humanos , Lisina/genética , Camundongos , Oxirredução , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
INTRODUCTION: Adherence to oral anticoagulation (OAC) treatment, vitamin K antagonists or new oral anticoagulants, is an essential element for effectiveness. Information on adherence to OAC in atrial fibrillation (AF) and the impact of adherence on clinical outcomes using real-world data barely exists. We aim to describe the patterns of adherence to OAC over time in patients with AF, estimate the associated factors and their impact on clinical events, and assess the same issues with conventional measures of primary and secondary adherence-proportion of days covered (PDC) and persistence-in routine clinical practice. METHODS AND ANALYSIS: This is a population-based retrospective cohort study including all patients with AF treated with OAC from 2010 to date in Valencia, Spain; data will be obtained from diverse electronic records of the Valencia Health Agency. PRIMARY OUTCOME MEASURE: adherence trajectories. SECONDARY OUTCOMES: (1) primary non-adherence; (2) secondary adherence: (a) PDC, (b) persistence. Clinical outcomes: hospitalisation for haemorrhagic or thromboembolic events and death during follow-up. ANALYSIS: (1) description of baseline characteristics, adherence patterns (trajectory models or latent class growth analysis models) and conventional adherence measures; (2) logistic or Cox multivariate regression models, to assess the associations between adherence measures and the covariates, and logistic multinomial regression models, to identify characteristics associated with each trajectory; (3) Cox proportional hazard models, to assess the relationship between adherence and clinical outcomes, with propensity score adjustment applied to further control for potential confounders; (4) to estimate the importance of different healthcare levels in the variations of adherence, logistic or Cox multilevel regression models. ETHICS AND DISSEMINATION: This study has been approved by the corresponding Clinical Research Ethics Committee. We plan to disseminate the project's findings through peer-reviewed publications and presentations at relevant health conferences. Policy reports will also be prepared in order to promote the translation of our findings into policy and clinical practice.
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Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Administração Oral , Fibrilação Atrial/complicações , Bases de Dados Factuais , Sistemas de Informação em Saúde , Hemorragia , Hospitalização/estatística & dados numéricos , Humanos , Modelos Logísticos , Análise Multivariada , Modelos de Riscos Proporcionais , Projetos de Pesquisa , Estudos Retrospectivos , Espanha , TromboemboliaRESUMO
OBJECTIVES: Beyond the current economic crisis, the Spanish National Health System (SNHS) has a problem of long-term sustainability that has its roots in changes in the morbidity patterns with the onset of chronic diseases and the acceleration of technological change, and with the rapid incorporation of new and expensive technologies. The aim of this paper is to explore the role of low value technology disinvestment as a strategy for SNHS sustainability. MATERIAL AND METHODS: Narrative review and discussion of the relevant features of disinvestment, and disinvestment strategies in several countries. RESULTS: Disinvestment is an explicit process of (partially or completely) withdrawing drugs, devices, practices or procedures with low or questionable clinical value. Very dissimilar healthcare systems such as those in Australia, New Zealand, United Kingdom or United States have launched disinvestment strategies adapted to their different contexts, while in Spain there remains a degree of reluctance to incorporate explicit mechanisms for decision-making on incorporation/disinvestment of health technologies with regard to the SNHS. DISCUSSION: Low value technology disinvestment is complex. Many technologies are only candidates for partial withdrawal, or its value is controversial and, in addition, there are psychological and sociological barriers to disinvestment. Implementation of these strategies requires commitment from professionals and health authorities and cooperation from patients and citizens, which in turn should be carefully managed.
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Alocação de Recursos para a Atenção à Saúde/organização & administração , Política de Saúde , Medicina Estatal/organização & administração , Avaliação da Tecnologia Biomédica , Análise Custo-Benefício , Avaliação de Programas e Projetos de Saúde , EspanhaRESUMO
We experimentally demonstrate multi-beam high spatial resolution laser micromachining with femtosecond pulses. The effects of chromatic aberrations as well as pulse stretching on the material processed due to diffraction were significantly mitigated by using a suited dispersion compensated module (DCM). This permits to increase the area of processing in a factor 3 in comparison with a conventional setup. Specifically, 52 blind holes have been drilled simultaneously onto a stainless steel sample with a 30 fs laser pulse in a parallel processing configuration.
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UNLABELLED: This study provides information on the prevalence of the most important risk factors for osteoporosis and osteoporotic fracture in a large sample of women and men from the Valencia region and also provides the FRAX 10-year major and hip fracture risks for this population, as well as data about the use of diagnostic tests and antiosteoporotic treatments. INTRODUCTION: The purpose of this study was to describe demographic characteristics, osteoporosis risk factors, the 10-year risk of osteoporotic fracture, and the use of densitometry and antiosteoporotic treatments in the Valencia region, Spain. METHODS: A cross-sectional study using the ESOSVAL cohort baseline data was conducted. We analyze the data from 5,310 women and 5,725 men aged 50 and over who attended to 272 collaborating primary care centers in 2009-2010. We collected the demographic, anthropometric, clinical, and pharmacy data from the electronic medical record. RESULTS: The mean age of participants was 64.3 years old for women and 65.6 years old for men. The most frequent fracture risk factors were sedentary life (22.2 %) and previous fracture (15.8 %) in women and low calcium intake (21.4 %) and current smoker (20.9 %) in men. According to FRAX(®), the 10-year risk of presenting a major fracture was 5.5 % for the women and 2.8 % for the men. The 10-year risk for hip fracture was 1.9 and 1.1 % for the women and the men, respectively; 23.8 % of the women and 5.2 % of the men had a densitometry test, 27.7 % of the women and 3.5 % of the men were taking calcium and/or vitamin D supplements, and 28.2 % of the women (22.0 % in the 50-64 age group) and 2.3 % of the men were taking antiosteoporotic drugs. CONCLUSIONS: The prevalence of certain fracture risk factors not included in the FRAX tool (sedentary life, falls, low calcium intake) is high. In young women, their low risks estimated by FRAX contrast with the high figures for densitometry testing and treatment.
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Conservadores da Densidade Óssea/uso terapêutico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Acidentes por Quedas/estatística & dados numéricos , Idoso , Densidade Óssea/fisiologia , Cálcio da Dieta/administração & dosagem , Estudos Transversais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/tratamento farmacológico , Osteoporose/epidemiologia , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Prevalência , Recidiva , Fatores de Risco , Comportamento Sedentário , Fumar/efeitos adversos , Fumar/epidemiologia , Espanha/epidemiologiaRESUMO
Measurement of urine and plasma melamine-concentration is helpful in confirming melamine-associated renal diseases. A chromatographic procedure using a C18 column and a micellar mobile phase of sodium dodecyl sulphate (0.2M), buffered at pH 3 and detection set at 210 nm, was reported for the resolution and quantification of melamine in plasma and urine. In this work, direct injection was used, thus avoiding long extraction and experimental procedures. Melamine was eluted in nearly 6.3 min without overlapping the protein band or other endogenous compounds. The optimal mobile phase composition was taken by studying the influence of each chromatographic parameter. Validation was satisfactorily performed following the US Food and Drug Administration (FDA), in terms of: linearity (0.25-25 ppm; r2>0.9995 in both cases), sensitivity, limit of detection (50 ppb), limit of quantification (250 ppb), intra- and inter-day precision (R.S.D. 0.7-10.2% and 1.0-9.1%, respectively) and recovery, calculated as accuracy (85.7-103.8% and 94.8-103.6%, respectively) and robustness (R.S.D.<7.1%). The suggested methodology has been applied to the analysis of real samples of volunteers, and no melamine was found in any of them.
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Líquidos Corporais/química , Triazinas/sangue , Triazinas/urina , Adulto , Calibragem , Cromatografia Líquida , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Micelas , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dodecilsulfato de Sódio/químicaRESUMO
Snail1 is a transcriptional factor essential for triggering epithelial-to-mesenchymal transition. Moreover, Snail1 promotes resistance to apoptosis, an effect associated to PTEN gene repression and Akt stimulation. In this article we demonstrate that Snail1 activates Akt at an additional level, as it directly binds to and activates this protein kinase. The interaction is observed in the nucleus and increases the intrinsic Akt activity. We determined that Akt2 is the isoform interacting with Snail1, an association that requires the pleckstrin homology domain in Akt2 and the C-terminal half in Snail1. Snail1 enhances the binding of Akt2 to the E-cadherin (CDH1) promoter and Akt2 interference prevents Snail1 repression of CDH1 gene. We also show that Snail1 binding increases Akt2 intrinsic activity on histone H3 and have identified Thr45 as a residue modified on this protein. Phosphorylation of Thr45 in histone H3 is sensitive to Snail1 and Akt2 cellular levels; moreover, Snail1 upregulates the binding of phosphoThr45 histone H3 to the CDH1 promoter. These results uncover an unexpected role of Akt2 in transcriptional control and point out to phosphorylation of Thr45 in histone H3 as a new epigenetic mark related to Snail1 and Akt2 action.
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Caderinas/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição/metabolismo , Antígenos CD , Caderinas/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Transição Epitelial-Mesenquimal , Fibronectinas/genética , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/genética , Fatores de Transcrição da Família SnailRESUMO
UNLABELLED: Semi-automatic morphometry is highly reproducible and not time intensive; however, no study has evaluated agreement between semi-automated morphometric methods and the Genant semi-quantitative method performed as a rule by radiologists. Our study shows substantial agreement between both methods; however, semi-automatic morphometry upgrades mild deformities and overestimates the prevalence of fractures. INTRODUCTION: The aim of this study was to evaluate the agreement between radiologists using the Genant semi-quantitative (SQ) method and semi-automated morphometry in the diagnosis of vertebral fractures in post-menopausal women. METHODS: Cross-sectional study was conducted in 2006-2007 in an age-stratified population-based sample of 824 post-menopausal women over the age of 50. From this population two sets of 95 and 50 X-ray were randomly extracted to test inter-rater agreement and agreement between SQ and semi-automated morphometry, and vertebral fractures were classified according to both methods. The Genant method was used to homogenise the diagnosis of fractures. Agreement was evaluated with weighted kappa. We evaluated each vertebral body independently and also the whole vertebral column (T4-L4) classifying women into the worst grade of fracture. For the qualitative interpretation of the agreement, we used the criteria described by Landis and Koch (Biometrics 33:159-174, 1977). RESULTS: The radiologists' agreement was 98.4% (Kappa, 0.75; 95% CI, 0.42-0.89). Agreement between semi-automated morphometry and SQ reached 97.6% and Kappa was 0.86 (95% CI, 0.66-0.94). In the whole evaluation of the spine semi-automated morphometry overestimates, the prevalence of fractures compared with the radiologists were 15.8% of women with fractures and 7.4% of women with moderate-severe fractures by semi-automated morphometry vs. 8.4% and 3.2% by the SQ method. The negative predictive value for MorphoXpress was 99% while the positive was 40%. CONCLUSIONS: Semi-automated morphometry shows high reliability and a substantial agreement with the SQ approach but overestimates the prevalence of fractures. Its role in routine clinical practice is limited because positive results should be reassessed by qualitative or semi-quantitative methods.
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Vértebras Lombares , Fraturas por Osteoporose/diagnóstico por imagem , Radiologia/estatística & dados numéricos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Variações Dependentes do Observador , Fraturas por Osteoporose/epidemiologia , Pós-Menopausa , Radiografia , Radiologia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espanha/epidemiologia , Fraturas da Coluna Vertebral/epidemiologia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesõesRESUMO
OBJECTIVE: Greater saphenous vein harvest for coronary and lower extremity bypass requires the longest incision of any surgical procedure. Endoscopic vein harvest allows better results in some clinical variables compared to open harvesting techniques. The objective of this study is to present the results of a systematic review of the scientific evidence about the efficiency of endoscopic saphenous vein harvest. METHODS: We performed a systematic review in the bibliographical databases Pubmed, National Health Service Economic Evaluation Database, and NHS Health Technology Assessment Database. The search strategy was "endoscopic AND harvesting", in the period January 1970-December 2009. RESULTS: We identified only 3 economic evaluation studies, 2 cost analyses with some methodological limitations, and 1 cost-utility analysis. All of them suggest lower hospital costs for endoscopic harvesting. CONCLUSIONS: Available evidence does not allow recommendations to be made based on the efficiency of endoscopic saphenous vein harvest, although it suggests lower costs for endoscopic harvesting. More scientific evidence about the long-term efficacy and the effectiveness of this technique is necessary, with studies measuring final outcomes, and carrying out complete and rigorous economic evaluations.
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Endoscopia/economia , Veia Safena/cirurgia , Coleta de Tecidos e Órgãos/economia , Procedimentos Cirúrgicos Vasculares/economia , Análise Custo-Benefício , HumanosAssuntos
Prescrições de Medicamentos , Aceitação pelo Paciente de Cuidados de Saúde , Relações Médico-Paciente , Atitude do Pessoal de Saúde , Dissidências e Disputas , Substituição de Medicamentos , Médicos Hospitalares , Humanos , Prescrição Inadequada , Medicina , Médicos de Família , Encaminhamento e ConsultaRESUMO
Hydroxytyrosol is a well-known natural phenolic component obtained from olive extract samples with antioxidant effects. A micellar liquid chromatography method to detect and quantify hydroxytyrosol in olive extract samples is described. Matrix resolution was performed using a Kromasil C18 column and a micellar mobile phase of sodium dodecyl sulphate (SDS) 0.05M and 4% methanol buffered at pH 7. Detection was set by absorbance at 280nm. Samples were diluted with 0.05M SDS at pH 3 and directly injected, thus avoiding long tedious extractions. Hydroxytyrosol was eluted in 3.5min without overlapping other matrix compounds. Validation was performed following the US FDA guideline. The main analytical parameters studied were: linearity (0.03-250µgmL-1; r2=0.999), limit of detection and quantification (3 and 30ngmL-1, respectively), intra- and inter-day precision (RSD, % <1.4 and <8.2, respectively), and robustness (RSD, %<6.6). Recoveries were in the 88.5-98.9% range.
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Arteriviruses are a group of small enveloped viruses with a genome composed of a positive, single-stranded, 5'-capped and 3'-polyadenylated RNA molecule. These viruses belong to the Arteriviridae family which together with the Coronaviridae and Roniviridae families constitutes the order Nidovirales. Arteriviruses have a marked tropism for macrophages and induce persistent infections. Several studies have reported the unique genomic organization of these viruses together with replication and transcription mechanisms for the synthesis of genomic and sub-genomic viral RNAs which, for the latter, encode viral structural proteins. Several sequences are now available for these viruses. Recent studies about the modulation of innate immune response by arteriviruses also demonstrated a key-role of particular non structural proteins in that process. Finally, certain pro- and anti-apoptotic mechanisms associated to Arteriviruses have been elucidated; however the exact significance of theses apoptotic processes in arterivirus pathogenesis has yet to be determined.
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The polarization-dependent guiding properties of a hexagonal-lattice photonic crystal fiber with a solid-core surrounded by four large air holes are investigated. The appearance of a polarization dependent cutoff frequency, together with several parameters as the birefringence, the modal effective area, the group velocity dispersion and the polarization dependent loss are analyzed. A collection of fibers with different structural parameters were fabricated and characterized. An effective anti-guide structure from at least 450 nm to 1750 nm, a polarizing fiber with a polarization dependent loss of 16 dB/m at 1550 nm, and an endlessly singlemode polarization-maintaining fiber with group birefringence of 2.1x10(-3) at 1550 nm are reported. Experimental results are compared with accurate numerical modeling of the fibers.