Plasmon-enhanced multi-photon excited photoluminescence of Au, Ag, and Pt nanoclusters.

In this work, we have studied the multi-photon excited photoluminescence from metal nanoclusters (NCs) of Au, Ag and Pt embedded in Al2O3matrix by ion implantation. The thermal annealing process allows to obtain a system composed of larger plasmonic metal nanoparticles (NPs) surrounded by photoluminescent ultra-small metal NCs. By exciting at 1064 nm, visible emission, ranging from 450 to 800 nm, was detected. The second and fourth-order nature of the multiphoton process was verified in a power-dependent study measured for each sample below the damage threshold. Experiments show that Au and Ag NCs exhibit a four-fold enhanced multiphoton excited photoluminescence with respect to that observed for Pt NCs, which can be explained as a result of a plasmon-mediated near-field process that is of less intensity for Pt NPs. These findings provide new opportunities to combine plasmonic nanoparticles and photoluminescent nanoclusters inside a robust inorganic matrix to improve their optical properties. Plasmon-enhanced multiphoton excited photoluminescence from metal nanoclusters may find potential application as ultrasmall fluorophores in multiphoton sensing, and in the development of solar cells with highly efficient energy conversion modules.

Tuning the aspect ratio of silver nanospheroids embedded in silica: erratum.

We present a corrigendum to our Letter [Opt. Lett.35, 703 (2010)10.1364/OL.35.000703]. In the original Letter we inadvertently included in Fig. 2(a) a TEM micrograph corresponding to a different, but very similar, sample. This corrigendum replaces Fig. 2(a) with a correct version. Since the main results are rather based in optical absorption measurements, and their modeling by using the T-matrix method, this correction does not affect the results and conclusions of the original Letter.

Extracellular vesicles in low volume uterine lavage and serum: novel and promising biomarker for endometritis in Arabian mares.

BACKGROUND: Extracellular vesicles (EVs) are a promising biomarker and play a vital role in cell-cell communication. This study aimed (I) to identify and characterize EVs from low volume uterine lavage (LVL) and serum in mares with endometritis, compared to healthy controls and (II) to measure serum levels of interleukin 6 (IL-6), and prostaglandins (PGF2α and PGE2). Mares were divided into 30 sub-fertile (endometritis) and 20 fertile (controls). Serum and LVL was collected for EV isolation, and determination of serum levels of inflammatory mediators. Characterization and visualization of EVs were done by electron microscopy, dynamic light scattering and flow cytometry. RESULTS: Serial ultracentrifugation of LVL and use of a commercial kit for serum were strategies for EVs isolation. Mares with endometritis released higher amounts of larger size EVs. The EVs from mares with endometritis differentially expressed CD9 and CD63, compared to controls. Mares suffering from endometritis evoked higher levels of inflammatory mediators. CONCLUSIONS: Thus, EVs could be used for a better understanding the regulatory mechanisms associated with developing endometritis in mares.

New insights into molecular aspects of sperm-oviductal binding in Egyptian buffaloes using an in vitro model: Effects of oviductal segments and media.

We aimed (I) to simulate an in vivo milieu, through establishing an in vitro paradigm to study sperm-oviductal interactions using different segments of oviduct, as well as different incubation media, and (II) to investigate spatial changes of oviductal gene expression. Two experiments were designed; one was to investigate the yield of oviduct aggregates from different oviduct segments; in the second experiment, we observed effects of different incubation media on sperm-oviductal binding. Oviduct cell pellets before (control) and after sperm binding were collected for RNA isolation and gene expression. Isthmus resulted in a higher aggregate yield and possessed the highest affinity towards spermatozoa. The different segments of oviduct showed clear changes in gene expression after sperm binding. TALP medium promoted formation of a higher number of oviduct aggregates towards spermatozoa. Different media resulted in profound alterations in isthmus gene expression. Collectively, isthmus segment in TALP media showed the highest binding affinity to spermatozoa. At the molecular level, our in vitro model was successful for simulation in vivo milieu. Thus, our findings could be used as a simple tool to gain more insights into the molecular regulation of sperm movement, selection and affinity for oviductal binding in buffaloes.

Inflammatory response induced by Helicobacter pylori infection in lung.

Helicobacter pylori is a microorganism that in the last years has been associated with extragastric disorders such as respiratory diseases, however, its impact on lung is partially understood. The aim of this work was to study infection impact of H. pylori on the inflammatory markers expression at the pulmonary level using an animal model. Infection was performed by BALB/c wild type (WT) mice orotracheal instillation with 20 µl of 1 × 108H. pylori reference strain suspension once per day throughout 3 days. Inflammatory response was evaluated at 3, 7, 14, 21 and 30 days post infection. Lung was aseptically removed and pulmonary edema index values showed a significant change at 30 days of infection. Hematoxylin-Eosin (H-E) stain allowed to visualizing H. pylori presence in lung samples at 3 days of infection near the phagocytic cells or in the alveoli lumen. Bronchoalveolar lavage (BAL) was used for inflammatory response evaluation. Lactate dehydrogenase values showed a gradual increase in infected animals along infection time. Protein concentrations in mg/ml from BAL increased significantly at 7 days in infected animals. Macrophages viability obtained from BAL, decreased at the first moment of infection, maintaining constant values along contamination time. Results obtained demonstrate an inflammatory response in lung after orotracheal H. pylori infection and suggest that the pathogenic mechanism is strongly evidenced by tissue damage, endothelial dysfunction inflammatory mediators and markers expression at the pulmonary level.

Impact of nano-selenium on nuclear maturation and genes expression profile of buffalo oocytes matured in vitro.

Supplementation of maturation media with antioxidant (bulk form) improves oocyte maturation. However, the influence of adding antioxidant (nano-particles) on oocyte maturation is not well known. We aimed to evaluate the effect of selenium nano-particles (SeNP) and bulk selenium (Se) on buffalo oocytes maturation, in terms nuclear maturation and molecular level. Oocytes were distributed into four groups; 1st group was control, 2nd group was supplied with Se (10 ng/ml), 3rd and 4th groups were supplied with 1 µg/ml SeNP (67 nm), and SeNP (40 nm), respectively. Matured oocytes were fixed and stained to determine nuclear maturation. Oocytes and COC after IVM were stored at - 80 °C, for RNA isolation and qRT-PCR for selected genes. The Se and seNP (40 nm) had a positive effect on oocytes nuclear maturation rates. Apoptosis-related cysteine peptidase (CASP3) was reduced in all supplemented groups. Anti-Mullerian hormone (AMH) was up-regulated in oocytes supplemented with SeNP (40 nm). In COC, AMH increased in group supplemented with SeNP (67 nm). In oocytes, phospholipase A2 group III (PLA2G3) decreased in all supplemented groups. While in COC, PLA2G3increased in group supplied with Se. In COC, luteinizing hormone/choriogonadotropin receptor (LHCGR) increased in groups supplied with Se or SeNP (40 nm).Glutathione peroxidase 4 (GPX4) increased in all supplemented groups, in oocytes and COC. In oocytes, superoxide dismutase (SOD) was up-regulated in supplemented groups {Se and SeNP (67 nm)}.The DNA methyltransferase (DNMT) in oocytes was reduced in supplemented groups. In oocytes, the POU class 5 homeobox 1 (OCT4) increased in all supplemented groups. In COC, the OCT4 was over-expressed in group supplemented with SeNP (40 nm). Selenium supplementation in bulk or nano-particle improved in vitro buffalo oocytes maturation, viaup-regulation of antioxidant defense and development competence genes. SeNP (smaller size, 40 nm) induced higher expression of antioxidant gene.

Study of Helicobacter pylori infection on lung using an animal model.

Helicobacter pylori infection has been reported to be associated with extra-digestive disorders such as respiratory diseases; however, the impact of H. pylori on lung is incompletely understood. Inflammatory response is mediated by the release of cytokines, interferon, and enzymes such as metalloproteinases (MMPs). This may contribute to collagen accumulation during the early phase of infection. MMP expression is an important factor for the proliferation and infiltration of lung cells in the process of fibrosis formation. The aim of this work was to study the impact of the infection with H. pylori on lung using a mouse model. We looked for histological lesions of lung infected with the microorganism as well as the expression of inflammatory and of endothelial dysfunction markers. C57BL/6 wild type (WT) mice were infected by orotracheal instillation with 20 µl of 1 × 108H. pylori reference strain suspension once per day for 3 days. Animals infected and controls were sacrificed at 3, 7, 14, 21 and 30 days. The lung from mice were stained with Hematoxylin-Eosin (H-E), Masson's Trichromic and Periodic Acid Schifft (PAS) for histological study. Also, lipid hydroperoxides and enzime catalase (CAT) activity were determined. Expression level of multiple markers implicated in inflammation (tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-4, IL-6, IL-8, IL-10; metalloproteinase MMP-9) and markers of endothelial dysfunction (I-CAM and V-CAM) was determined from lung tissues mRNA using RT-PCR. Results showed that H. pylori induced morphological changes in the lung tissue with recruitment of inflammatory cells and lung parenchymal cell degradation. The mRNA of IL-1ß and TNF-α; MMP-9, I-CAM and V-CAM increased at 3-7 days infections. Also, iNOS, IL-8 and Phosphocholine cytidyltransferase (CCT) increased with lung injury. Anti-inflammatory interleukin as: IL-4, and IL-10 increased at 7 and 14 days post infection respectively. The results obtained suggest that the pathogenic mechanism of H. pylori on lung could be strongly associated with lung injury as indicate the expression increased of inflammatory mediators and markers of endothelial dysfunction.

Large scale, prospective screening of EGFR mutations in the blood of advanced NSCLC patients to guide treatment decisions.

BACKGROUND: In a significant percentage of advanced non-small-cell lung cancer (NSCLC) patients, tumor tissue is unavailable or insufficient for genetic analyses. We prospectively analyzed if circulating-free DNA (cfDNA) purified from blood can be used as a surrogate in this setting to select patients for treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). PATIENTS AND METHODS: Blood samples were collected in 119 hospitals from 1138 advanced NSCLC patients at presentation (n = 1033) or at progression to EGFR-TKIs (n = 105) with no biopsy or insufficient tumor tissue. Serum and plasma were sent to a central laboratory, cfDNA purified and EGFR mutations analyzed and quantified using a real-time PCR assay. Response data from a subset of patients (n = 18) were retrospectively collected. RESULTS: Of 1033 NSCLC patients at presentation, 1026 were assessable; with a prevalence of males and former or current smokers. Sensitizing mutations were found in the cfDNA of 113 patients (11%); with a majority of females, never smokers and exon 19 deletions. Thirty-one patients were positive only in plasma and 11 in serum alone and mutation load was higher in plasma and in cases with exon 19 deletions. More than 50% of samples had <10 pg mutated genomes/µl with allelic fractions below 0.25%. Patients treated first line with TKIs based exclusively on EGFR positivity in blood had an ORR of 72% and a median PFS of 11 months. Of 105 patients screened after progression to EGFR-TKIs, sensitizing mutations were found in 56.2% and the p.T790M resistance mutation in 35.2%. CONCLUSIONS: Large-scale EGFR testing in the blood of unselected advanced NSCLC patients is feasible and can be used to select patients for targeted therapy when testing cannot be done in tissue. The characteristics and clinical outcomes to TKI treatment of the EGFR-mutated patients identified are undistinguishable from those positive in tumor.

Nonlinear optical response of platinum nanoparticles and platinum ions embedded in sapphire.

We report on the fabrication of sapphire samples containing platinum nanoparticles (Pt-NPs) and platinum ions (Pt-ions) and the investigation of their third-order nonlinear (NL) optical properties. The presence of Pt-NPs was confirmed by electronic microscopy and by the linear absorption spectrum that shows a localized surface plasmon band centered at 290 nm. A sample without NPs but containing Pt-ions was also studied. The absorptive and refractive contributions to the nonlinearity were studied using the z-scan technique with 100 fs pulses at 800nm. The experiments revealed a NL refractive index, +3.8×10-13 < n2 < +1.3×10-12cm2/W and NL absorption coefficient (ß < 9.3 cm/GW). The results show enhancement of about five orders of magnitude with respect to the NL refractive index of sapphire.

Evaluation of cytotoxicity and genotoxicity of Acacia aroma leaf extracts.

Acacia aroma, native plant from San Luis, Argentina, is commonly used as antiseptic and for healing of wounds. The present study was conducted to investigate the in vitro cytotoxicity and genotoxicity of hot aqueous extract (HAE) and ethanolic extract (EE) of A. aroma. The cytotoxic activity was assayed by neutral red uptake assay on Vero cell. Cell treatment with a range from 100 to 5000 µg/mL of HAE and EE showed that 500 µg/mL and 100 µg/mL were the maximum noncytotoxic concentrations, respectively. The CC50 was 658 µg/mL for EE and 1020 µg/mL for HAE. The genotoxicity was tested by the single-cell gel electrophoresis comet assay. The results obtained in the evaluation of DNA cellular damage exposed to varied concentrations of the HAE showed no significant genotoxic effect at range of 1-20 mg/mL. The EE at 20 mg/mL showed moderate genotoxic effect related to the increase of the DNA percentage contained in tail of the comet; DNA was classified in category 2. At concentrations below 5 mg/mL, the results of cytotoxicity and genotoxicity of aqueous and ethanolic extracts of Acacia aroma guarantee the safety at cell and genomic level. However further studies are needed for longer periods including animal models to confirm the findings.

Workplace aggressions on hospital workers: A current and prevalent problem with a high demand for training.

BACKGROUND: Workplace aggressions on hospital workers is a very frequent and under-reported problem. OBJECTIVE: The novel objective of our study was to analyze the number of workplace aggressions per hospital worker. Other objectives of the study were to analyze the management knowledge and interest in receiving training on aggressions by hospital workers. METHODS: An anonymous survey was handed out among all professionals in a university hospital. RESULTS: A total of 1118 anonymous surveys were collected. The responders declared that throughout their working life they had suffered some sort of verbal aggression in the hospital in 766 cases (68.5%) and physical aggression in 393 cases (35.2%). Multiple logistic regression analyses found higher risk of receiving physical and verbal aggression in the nursing category and in the Emergency, Critical Care or Psychiatry Units, and a higher risk of receiving physical aggression in women. The score on the level of personal knowledge regarding the legal, physical, and psychological management of aggressions (score 0-10 for each of the 3 aspects) was 2.91±2.68 in legal management, 2.97±2.77 in psychological management and 2.91±2.76 in physical management. The opinion about the interest of receiving training (score from 0 to 10) on the legal management of hospital aggressions was 8.90±1.72, on psychological management was 8.85±1.78 and on physical management was 8.88±1.78. CONCLUSIONS: Workplace aggression on hospital workers mainly affects women, the nursing category and the Emergency, Critical Care or Psychiatry Units. Hospital workers showed little knowledge on the topic but a great interest in receiving training.

Are GES carbapenemases underdiagnosed? An allelic discrimination assay for their accurate detection and differentiation.

GES (Guiana Extended Spectrum) carbapenemases belong to "minor class A carbapenemases" and its prevalence could be underestimated due to the lack of specific tests. The aim of this study was to develop an easy PCR method to differentiate between GES ß-lactamases with or without carbapenemase activity, based on an allelic discrimination system of SNPs that encode E104K and G170S mutations, without need of sequencing. Two pair of primers and Affinity Plus probes, labeled with different fluorophores; FAM/IBFQ and YAK/IBFQ, were designed for each one of the SNPs. This allelic discrimination assay allows to detect in real time the presence of all type of GES- ß-lactamases, being able to differentiate between carbapenemases and extended-spectrum ß-lactamase (ESBL), through a quick PCR test that avoid costly sequencing approaches and could help to decrease the current underdiagnosis of minor carbapenemases that scape of phenotypic screenings.

Clinical validation of the European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE) II criteria in an open-access unit: a prospective study.

BACKGROUND AND STUDY AIMS: The European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE I) criteria were recently updated (EPAGE II), but no prospective studies have used these criteria in clinical practice. The aim of the current study was to validate the EPAGE II criteria in an open-access endoscopy unit. PATIENTS AND METHODS: A prospective observational study was conducted in an open-access endoscopy unit at a tertiary care referral center. Consecutive outpatients (n = 1004; mean age 58.9 ±â€†13.1 years; 45 % men) were referred for diagnostic colonoscopy between September 2009 and February 2010. The appropriateness of colonoscopy was assessed based on EPAGE II criteria, and the relationship between appropriateness and both referral doctor and detection of significant lesions was examined. The effectiveness of EPAGE II criteria in assessing appropriateness was measured by means of sensitivity, specificity, and positive and negative predictive values for detecting significant lesions. RESULTS: Colonoscopic cecal intubation was achieved in 956 patients (95.2 %). Most referral doctors were gastroenterologists (58.0 %) and the most common indication was colorectal cancer (CRC) screening (35.2 %). EPAGE II criteria were applicable in 968 patients (96.4 %); of these patients, the indication was appropriate in 778 (80.4 %), inappropriate in 102 (10.5 %), and uncertain in 88 (9.1 %). Patients with appropriate or uncertain indications based on EPAGE II criteria had more relevant endoscopic findings than those with inappropriate indications (38.8 % vs. 24.5 %; OR 1.95, 95 %CI 1.22 - 3.13; P < 0.005). Sensitivity and negative predictive value of EPAGE II criteria for detecting significant lesions were 93.1 % (95 %CI 90 % - 96 %) and 75.5 % (95 %CI 67 % - 84 %), respectively, whereas for advanced neoplastic lesions these values were 98.0 % (95 %CI 95 % - 100 %) and 98.0 % (95 % CI 95 % - 100 %), respectively. Adherence to EPAGE II recommendations was an independent predictor of finding a significant lesion (OR 1.93, 95 %CI 1.20 - 3.11; P = 0.007). CONCLUSIONS: EPAGE II is a simple, valid score for detecting inappropriate colonoscopies in clinical practice.

Peripheral blood lymphocyte phenotypes in Alzheimer and Parkinson's diseases.

INTRODUCTION: Neuroinflammation is involved in the pathophysiology of various neurological disorders, in particular Alzheimer disease (AD) and Parkinson's disease (PD). Alterations in the blood-brain barrier may allow peripheral blood lymphocytes to enter the central nervous system; these may participate in disease pathogenesis. OBJECTIVE: To evaluate the peripheral blood lymphocyte profiles of patients with AD and PD and their association with the disease and its progression. METHODS: The study included 20 patients with AD, 20 with PD, and a group of healthy individuals. Ten of the patients with AD and 12 of those with PD were evaluated a second time 17 to 27 months after the start of the study. Lymphocyte subpopulations and their activation status were determined by flow cytometry. All patients underwent neurological examinations using internationally validated scales. RESULTS: Compared to healthy individuals, patients with AD and PD showed significantly higher levels of activated lymphocytes, lymphocytes susceptible to apoptosis, central memory T cells, and regulatory T and B cells. As the diseases progressed, there was a significant decrease in activated cells (CD4+ CD38+ and CD8+ CD38+ in PD and AD, CD4+ CD69+ and CD8+ CD69+ in PD), T cells susceptible to apoptosis, and some regulatory populations (CD19+ CD5+ IL10+ in PD and AD, CD19+ CD5+ IL10+ FoxP3+, CD4+ FoxP3+ CD25+ CD45RO+ in PD). In patients with AD, disease progression was associated with lower percentages of CD4+ CD38+ cells and higher percentages of effector CD4 cells at the beginning of the study. Significant differences were observed between both diseases. CONCLUSIONS: This study provides evidence of changes in peripheral blood lymphocyte phenotypes associated with AD and PD and their severity. Considering effective blood-brain communication, our results open new avenues of research into immunomodulation therapies to treat these diseases.

Spatiotemporal expression pattern of miR-205, miR-26a-5p, miR-17-5p, let-7b-5p, and their target genes during different stages of corpus luteum in Egyptian buffaloes.

BACKGROUND: No doubt that the corpus luteum (CL) plays a vital role in the regulation of female cyclicity in mammals. The scenarios among microRNAs (miRNAs) and their target genes and steroid hormones {estradiol (E2) and progesterone (P4)} are required for better understanding the molecular regulation of CL during its formation, maturation, and regression. We aimed to (I) study the changes in the relative abundance of miR-205, miR-26a-5p, miR-17-5p, and let-7b-5p and their target genes: LHCGR, CASP3, PCNA, AMH, and PLA2G3, during different stages of corpus luteum in Egyptian buffaloes, and (II) and to address different scenarios between steroid concentrations in the serum and the expression pattern of selected miRNAs and their targets. METHODS: The paired ovaries and blood samples were collected from apparently healthy 50 buffalo cows at a private abattoir. The ovaries bearing CL were macroscopically divided according to their morphological structure and color into hemorrhagic (CLH), developing (CLD), mature (CLM), regressed (CLR), and albicans (CLA). Small pieces from different stages of CL (CLH, CLD, CLM, CLR, and CLA) were cut and immediately kept at - 80 °C for total RNA isolation and qRT-PCR. The serum was separated for steroid level estimation. RESULTS: The LHCGR was expressed during different stages of CL, and the peak of expression was at the mid-luteal stage. The CASP3 revealed a stage-specific response at different stages of CL. The PCNA has an essential role in cellular proliferation in buffaloes CL. Both expression patterns of PLA2G3 and AMH were found over the various developmental and regression stages. It was noticed that miR-205 is conserved to target LHCGR and CASP3 transcripts. Moreover, CASP3 and AMH were targeted via miR-26a-5p. Additionally, the CASP3 and PLA2G3 were targeted via let-7b-5p. The P4 level reached its peak during CLM. There were positive and negative strong correlations between miRNAs (miR-26a-5p and miR-205), target genes (LHCGR and CASP3) during different stages of CL, and steroid hormones in the serum. CONCLUSIONS: Taken together, the orchestrated pattern among miRNAs, target genes, and steroid hormones is essential for maintaining the proper development and function of CL in buffalo cows.

Economic impact of periprosthetic hip fractures.

INTRODUCTION: Hip replacement is one of the most successful operations in orthopaedic surgery. Periprosthetic hip fractures (PPHF) have very serious consequences for the patient, and they also entail a very important economic impact on healthcare systems. The aim of the study was to provide the first detailed cost analysis of PPHF in a traumatology and orthopaedics service in a third level hospital in Spain. METHODS: The study included all patients admitted between 2009 and 2019 with a diagnosis of "PPHF". We assessed hospital stay cost, total cost of the operating theatre, cost of the implants used, analyses, consultations with other specialists, rehabilitation sessions, radiological tests, microbiology, blood transfusions and other surgical operations during the same admission. RESULTS: 78 patients were included in the study, 49 women and 29 men, with a mean age of 78.74 years (R 45-92). 69 patients received surgical treatment, 75% had open reduction and internal fixation (ORIF), and 25% had revision surgery. The total cost was €1,139,650.17. The average cost was €14,610.90. Significantly higher costs were incurred for revision compared to ORIF treatments, admissions that lasted more than 30 days, and patients who required more than one operation during admission. The most costly factors were the hospital stay (46%), the cost of the surgery itself (35%), and the implants (24%). CONCLUSIONS: Revision arthroplasty versus ORIF treatment, admissions lasting more than 30 days, and patients requiring more than one operation on admission incurred significantly higher costs. The average cost, from a hospital perspective, generated by a PPHF was €14,610.90. The most costly factors were, in descending order, the hospital stay, the cost of the surgery itself, and the implants. It is necessary to establish protocols and updated therapeutic algorithms in the perioperative management of PPHF in order to reduce both morbidity rates and associated costs.

Economic impact of periprosthetic hip fractures. / [Artículo traducido] Impacto económico de las fracturas periprotésicas de cadera.

INTRODUCTION: Hip replacement is one of the most successful operations in orthopaedic surgery. Periprosthetic hip fractures (PPHF) have very serious consequences for the patient, and they also entail a very important economic impact on healthcare systems. The aim of the study was to provide the first detailed cost analysis of PPHF in a traumatology and orthopaedics service in a third level hospital in Spain. METHODS: The study included all patients admitted between 2009 and 2019 with a diagnosis of «PPHF¼. We assessed hospital stay cost, total cost of the operating theatre, cost of the implants used, analyses, consultations with other specialists, rehabilitation sessions, radiological tests, microbiology, blood transfusions and other surgical operations during the same admission. RESULTS: Seventy-eight patients were included in the study, 49 women and 29 men, with a mean age of 78.74 years (R 45-92). Sixty-nine patients received surgical treatment, 75% had open reduction and internal fixation (ORIF), and 25% had revision surgery. The total cost was €1 139 650.17. The average cost was €14 610.90. Significantly higher costs were incurred for revision compared to ORIF treatments, admissions that lasted more than 30 days, and patients who required more than one operation during admission. The most costly factors were the hospital stay (46%), the cost of the surgery itself (35%), and the implants (24%). CONCLUSIONS: Revision arthroplasty versus ORIF treatment, admissions lasting more than 30 days, and patients requiring more than one operation on admission incurred significantly higher costs. The average cost, from a hospital perspective, generated by a PPHF was €14 610.90. The most costly factors were, in descending order, the hospital stay, the cost of the surgery itself, and the implants. It is necessary to establish protocols and updated therapeutic algorithms in the perioperative management of PPHF in order to reduce both morbidity rates and associated costs.

First detection of SARS-CoV-2 variant B.1.1.529 (Omicron) in Ecuador.

The National Institute of Research and Public Health reported the first local record of the Omicron variant detected in Ecuador. A fully vaccinated subject returned from South Africa with a negative RT-PCR. We present the cumulative frequency of the variants in Ecuador and a phylogenetic analysis of this new Omicron.

Ultrafast optical phase modulation with metallic nanoparticles in ion-implanted bilayer silica.

The nonlinear optical response of metallic-nanoparticle-containing composites was studied with picosecond and femtosecond pulses. Two different types of nanocomposites were prepared by an ion-implantation process, one containing Au nanoparticles (NPs) and the other Ag NPs. In order to measure the optical nonlinearities, we used a picosecond self-diffraction experiment and the femtosecond time-resolved optical Kerr gate technique. In both cases, electronic polarization and saturated absorption were identified as the physical mechanisms responsible for the picosecond third-order nonlinear response for a near-resonant 532 nm excitation. In contrast, a purely electronic nonlinearity was detected at 830 nm with non-resonant 80 fs pulses. Regarding the nonlinear optical refractive behavior, the Au nanocomposite presented a self-defocusing effect, while the Ag one presented the opposite, that is, a self-focusing response. But, when evaluating the simultaneous contributions when the samples are tested as a multilayer sample (silica-Au NPs-silica-Ag NPs-silica), we were able to obtain optical phase modulation of ultra-short laser pulses, as a result of a significant optical Kerr effect present in these nanocomposites. This allowed us to implement an ultrafast all-optical phase modulator device by using a combination of two different metallic ion-implanted silica samples. This control of the optical phase is a consequence of the separate excitation of the nonlinear refracting phenomena exhibited by the separate Au and Ag nanocomposites.

A brief dementia screener suitable for use by non-specialists in resource poor settings--the cross-cultural derivation and validation of the brief Community Screening Instrument for Dementia.

OBJECTIVE: Brief screening tools for dementia for use by non-specialists in primary care have yet to be validated in non-western settings where cultural factors and limited education may complicate the task. We aimed to derive a brief version of cognitive and informant scales from the Community Screening Instrument for Dementia (CSI-D) and to carry out initial assessments of their likely validity. METHODS: We applied Mokken analysis to CSI-D cognitive and informant scale data from 15 022 participants in representative population-based surveys in Latin America, India and China, to identify a subset of items from each that conformed optimally to item response theory scaling principles. The validity coefficients of the resulting brief scales (area under ROC curve, optimal cutpoint, sensitivity, specificity and Youden's index) were estimated from data collected in a previous cross-cultural validation of the full CSI-D. RESULTS: Seven cognitive items (Loevinger H coefficient 0.64) and six informant items (Loevinger H coefficient 0.69) were selected with excellent hierarchical scaling properties. For the brief cognitive scale, AUROC varied between 0.88 and 0.97, for the brief informant scale between 0.92 and 1.00, and for the combined algorithm between 0.94 and 1.00. Optimal cutpoints did not vary between regions. Youden's index for the combined algorithm varied between 0.78 and 1.00 by region. CONCLUSION: A brief version of the full CSI-D appears to share the favourable culture- and education-fair screening properties of the full assessment, despite considerable abbreviation. The feasibility and validity of the brief version still needs to be established in routine primary care.