[Translated article] Lower mortality and readmission in patients with few comorbidities who underwent hip fracture surgery and were discharged early.

INTRODUCTION: Pre-operative delay in patients with hip fracture surgery (HF) has been associated with poorer outcomes; however, the optimal timing of discharge from hospital after surgery has been little studied. The aim of this study was to determine mortality and readmission outcomes in HF patients with and without early hospital discharge. MATERIAL AND METHODS: A retrospective observational study was conducted selecting 607 patients over 65years of age with HF intervened between January 2015 and December 2019, from which 164 patients with fewer comorbidities and ASA≤II were included for analysis and divided according to their post-operative hospital stay into early discharge or stay ≤4 days (n=115), and non-early or post-operative stay >4days (n=49). Demographic characteristics; fracture and surgical-related characteristics; 30-day and one-year post-operative mortality rates; 30-day post-operative hospital readmission rate; and medical or surgical cause were recorded. RESULTS: In the early discharge group all outcomes were better compared to the non-early discharge group: lower 30-day (0.9% versus 4.1%, p=.16) and 1-year post-operative (4.3% versus 16.3%, p=.009) mortality rates, as well as a lower rate of hospital readmission for medical reasons (7.8% versus 16.3%, p=.037). CONCLUSIONS: In the present study, the early discharge group obtained better results 30-day and 1-year post-operative mortality indicators, as well as readmission for medical reasons.

Lower mortality and readmission in patients with few comorbidities who underwent hip fracture surgery and were discharged early. / Menor mortalidad y reingreso en pacientes con pocas comorbilidades intervenidos de fractura de cadera y con alta precoz.

INTRODUCTION: Preoperative delay in patients with hip fracture surgery (HF) has been associated with poorer outcomes; however, the optimal timing of discharge from hospital after surgery has been little studied. The aim of this study was to determine mortality and readmission outcomes in HF patients with and without early hospital discharge. MATERIAL AND METHODS: A retrospective observational study was conducted selecting 607 patients over 65years of age with HF intervened between January 2015 and December 2019, from which 164 patients with fewer comorbidities and ASA ≤II were included for analysis and divided according to their postoperative hospital stay into early discharge or stay ≤4 days (n=115), and non-early or post-operative stay >4days (n=49). Demographic characteristics; fracture and surgical-related characteristics; 30-day and one-year postoperative mortality rates; 30-day postoperative hospital readmission rate; and medical or surgical cause were recorded. RESULTS: In the early discharge group all outcomes were better compared to the non-early discharge group: lower 30-day (0.9% vs 4.1%, P=.16) and 1-year postoperative (4.3% vs 16.3%, P=.009) mortality rates, as well as a lower rate of hospital readmission for medical reasons (7.8% vs 16.3%, P=.037). CONCLUSIONS: In the present study, the early discharge group obtained better results 30-day and 1-year postoperative mortality indicators, as well as readmission for medical reasons.

Ambientes y hábitos alimentarios: Un estudio cualitativo sobre cambios producidos durante la pandemia por Covid-19 en estudiantes universitarios

RESUMEN La pandemia por Covid-19 ha generado diversos cambios en la rutina diaria de las personas a nivel mundial, repercutiendo en los ambientes alimentarios habituales y hábitos relacionados. En los estudiantes universitarios, el cambio en los ambientes alimentarios ha impactado fuertemente debido al cierre de las casas de estudio. Sin embargo, existe escasa información en el país, acerca de las consecuencias que dicha modificación ha provocado. El objetivo fue explorar cómo han cambiado los ambientes y hábitos alimentarios de universitarios, debido a la pandemia por Covid-19. Se llevó a cabo un estudio transversal de tipo cualitativo. Los participantes fueron estudiantes pertenecientes a una facultad de una universidad pública de Chile. Se realizaron 15 entrevistas semiestructuradas en modalidad online. La narrativa de las entrevistas se analizó a través de un análisis temático, con un enfoque inductivo. Los resultados muestran dos temas principales: I) Compra y acceso a alimentos, en donde no se visualizaron grandes cambios en el ambiente de abastecimiento, pero si en los ambientes alimentarios de restauración y vía pública; II) Transición desde el ambiente alimentario institucional al doméstico, situación que modificó los hábitos alimentarios en la mayoría de los estudiantes, quienes declararon consumir preparaciones más caseras, además de percibir mayor tiempo disponible al momento de consumir alimentos, en comparación a aquel dado en contexto universitario pre pandémico. Se requiere reflexionar acerca de cómo los aspectos positivos en los ambientes y hábitos alimentarios pudieran favorecerse en una vuelta a la presencialidad en el ambiente académico.

ABSTRACT The COVID-19 pandemic has generated various changes in the daily routine of people worldwide, affecting the usual food environments and related habits. Among university students, the change in food environments has had a strong impact due to the closure of university campuses. However, there is little information in the country about the consequences that this modification has caused. The study aim was to explore how the environments and eating habits of university students changed due to the COVID-19 pandemic. A qualitative descriptive cross-sectional study was carried out. Participants correspond to students of a public university in Chile. Fifteen semi-structured interviews were conducted online. Interview narratives were analyzed through a thematic analysis, using an inductive approach. The results show two main themes: I) Purchase and access to food, where great changes were not seen in the supply environment, but in the food environments of restaurants and public roads; II) Transition from the institutional food environment to the domestic environment, a situation that modified the eating habits of most of the students, who declared consuming more homemade preparations, in addition to perceiving more time available at the time of consuming food, compared to that given in context pre-pandemic college. It is necessary to reflect on how the positive aspects in the environments and eating habits could be favored in a return to the presence in the academic environment.

Sun exposure and protection habits in transplant athletes: An international survey.

BACKGROUND: Transplant recipients are particularly prone to the development of skin cancer, and overexposure to UV radiation during outdoor activities increases the risk of carcinogenesis. OBJECTIVE: The aim of this study was to analyze sun-related behaviors and knowledge in transplant athletes, examine the frequency of sunburns, and explore associations with a history of skin cancer. MATERIALS AND METHODS: Cross-sectional descriptive study. Participants (n = 170) in the XXI World Transplant Games from >50 countries completed a questionnaire on sun protection habits and knowledge, type of transplant, immunosuppressive therapy, and personal history of skin cancer. RESULTS: The most common transplanted organs were the kidney (n = 79), the liver (n = 33), and the heart (n = 31). Overall, 61.3% of athletes had been doing sport for >15 years and 79.5% spent >1-2 h a day outdoors. Fifteen % of athletes had a history of skin cancer. The prevalence of sunburn in the previous year was 28.9%, higher in athletes aged <50 years (37.2%); without a primary school education (58.3%), not taking cyclosporin (32.6%), and athletes who played basketball (75%). The main sun protection measures used were sunscreen (68.9%) and sunglasses (67.3%). Use of a hat or cap was the only measure significantly associated with a reduced prevalence of sunburn. CONCLUSIONS: Despite high awareness that sun exposure increases the risk of skin cancer, sunburn was common in transplant athletes. Efforts should be made to strengthen multidisciplinary sun protection education strategies and ensure periodic dermatologic follow-up to prevent sun-induced skin cancer in this population.

Decoherence of photon entanglement by transmission through brain tissue with Alzheimer's disease.

The generation, manipulation and quantification of non-classical light, such as quantum-entangled photon pairs, differs significantly from methods with classical light. Thus, quantum measures could be harnessed to give new information about the interaction of light with matter. In this study we investigate if quantum entanglement can be used to diagnose disease. In particular, we test whether brain tissue from subjects suffering from Alzheimer's disease can be distinguished from healthy tissue. We find that this is indeed the case. Polarization-entangled photons traveling through brain tissue lose their entanglement via a decohering scattering interaction that gradually renders the light in a maximally mixed state. We found that in thin tissue samples (between 120 and 600 micrometers) photons decohere to a distinguishable lesser degree in samples with Alzheimer's disease than in healthy-control ones. Thus, it seems feasible that quantum measures of entangled photons could be used as a means to identify brain samples with the neurodegenerative disease.

Variables related to chronic immune thrombocytopenia: experience from a single center and comparison to a meta-analysis.

Classically, several variables have been related to the disease course of chronic primary immune thrombocytopenia (cITP), though to date, there is no consensus on their clinical relevance. In a recent systematic review, a meta-analysis was made and confirmed the existence of certain cITP-related variables that may be related to prognosis in pediatric patients. We retrospectively analyzed a cohort of patients diagnosed with ITP, identified prognostic variables, and compared our results to the variables described by the authors. A multivariate study revealed that older age at diagnosis and higher platelet count were the only independent variables related to cITP. Children up to age 4 years and those with lower platelet counts (below 20 × 109/L) were at lower risk for cITP.Conclusion: We therefore concluded that only age and platelet count at diagnosis are independent variables that should be considered when evaluating the risk of developing cITP. What is Known: • Around 20% of patients with immune thrombocytopenia progress to chronic disease as determined by a sustained platelet count below 100×109/L for more than 12 months. • A number of variables potentially related to the development of cITP are being studied, such as age, sex, cell count, and previous treatment. What is New: • This is a new group of patients diagnosed with ITP in which the platelet count and age at diagnosis are the only independent variables closely related to cITP. • In this new series, we could not confirm other variables previously related to cITP such as total leukocyte count or the absence of treatment at diagnosis.

Understanding the food-family relationship: A qualitative research in a Chilean low socioeconomic context.

Our life is comprised of, among other things, many food and eating decisions. Therefore, we are in a constant relationship with food. Although many health providers and researchers have recommended having a positive relationship with food for better health and well-being, what the human relationship with food entails is still unclear. The aim of this study is to explore the relationship with food among families in Chile, a country that has the highest rate of obesity among OECD countries. In this qualitative study, we conducted eight focus groups in three regions of Chile (North, Center, and South). We recruited women living with their partners and children who represented the family point of view. For data analysis, we used the Atlas.ti program and conducted a thematic analysis. We found that the family relationship with food had five dimensions: (1) An identity dimension that allowed families to describe themselves or some of their family members; (2) an emotional dimension in which family expressed feelings and emotions through food; (3) a social dimension in which family members got together through food; (4) a health dimension in which family related to food to obtain benefits from it or to avoid enemy food; (5) a practical dimension in which families were organized around food tasks. Our findings show that the relationship that Chilean families have with food is a complex phenomenon. All the dimensions should be taken in consideration to create or improve interventions that seek to improve eating habits or prevent nutrition-related diseases from a family perspective.

Optimization of a MALDI-Imaging protocol for studying adipose tissue-associated disorders.

Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) is increasingly recognized for its potential in the discovery of novel biomarkers directly from tissue sections. However, there are no MALDI IMS studies as yet on the adipose tissue, a lipid-enriched tissue that plays a pivotal role in the development of obesity-associated disorders. Herein, we aimed at developing an optimized method for analyzing adipose tissue lipid composition under both physiological and pathological conditions by MALDI IMS. Our studies showed an exacerbated lipid delocalization from adipose tissue sections when conventional strategies were applied. However, our optimized method using conductive-tape sampling and 2,5-dihydroxybenzoic acid (DHB) as a matrix, preserved the anatomical organization and minimized lipid diffusion from sample sections. This method enabled the identification of a total of 625 down-regulated and 328 up-regulated m/z values in the adipose tissue from a rat model of extreme obesity as compared to lean animals. Combination of MALDI IMS and liquid chromatography (LC)-MS/MS data identified 44 differentially expressed lipid species between lean and obese animals, including phospholipids and sphingomyelins. Among the lipids identified, SM(d18:0_18:2), PE(P-16:0_20:0), and PC(O-16:0_16:1) showed a differential spatial distribution in the adipose tissue of lean vs. obese animals. In sum, our method provides a valuable new tool for research on adipose tissue that may pave the way for the identification of novel biomarkers of obesity and metabolic disease.

[Predictive factors of bacteraemia in the patients seen in emergency departments due to infections]. / Factores predictores de bacteriemia en los pacientes atendidos en el Servicio de Urgencias por infección.

OBJECTIVE: The aim of the study was to analyze predictive factors of bacteraemia in patients seen in the emergency department (ED) for an episode of infectious disease. METHODS: Observational, retrospective and descriptive analytical study of all blood cultures extracted in an ED in adult patients (≥ 18 years) seen in ED due to infec-tious disease from 1-1-2019 to 1-7-2019. The follow-up was carried out during 30 days. Thirty-eight variables for predicting bacteraemia were assessed. They covered epidemiological, comorbidity, functional, clinical and analytical factors. Univariate and multivariate logistic regression analysis was performed. RESULTS: A total of 1,425 blood cultures were finally enrolled in the study. Of those were considered true bacteremia 179 (12.6 %) and as negative blood cultures 1,246 (87.4 %). Amongst negatives, 1,130 (79.3%) without growth and 116 (8.1%) as contaminants blood cultures. Five variables were significantly associated with true bacteraemia: serum procalcitonin (PCT) ≥ 0.51 ng/ml [odds ratio (OR): 4.52; 95% confidence interval (CI): 4.20-4.84, P <.001], temperature > 38.3°C [OR:1.60; 95% CI:1.29-1.90, P <.001], systolic blood pressure (SBP) < 100 mmHg [OR:3.68; 95% CI:2.78-4.58, P <.001], septic shock [OR:2.96; 95% CI:1.78-4.13, P <.001] and malignancy [OR:1.73; 95% CI:1.27-2.20, P <.001]. CONCLUSIONS: Several factors evaluated in an initial assessment in the ED, including serum PCT, temperature, hypotension (with/without septic shock) and being malignancy, were found to predict true bacteraemia.

The photo-elicitation of food worlds: A study on the eating behaviors of low socioeconomic Chilean women.

Traditional methods for studying eating behaviors include quantitative methods such as 24-h dietary recalls or food frequency questionnaires. Recently, visual methods such as photo-elicitation (PE) have been recognized as useful for studying and understanding eating behaviors. PE has been defined as the use of images during an interview. The goals of this study are to demonstrate the potential of PE for exploring the eating behaviors of Chilean women of low socioeconomic status and to show the advantages and disadvantages of PE from the participants' points of view. The study included 31 participants who were asked to take pictures that represented what they considered important to them in their "food world". The pictures were developed and participants were invited to participate in an individual interview. Participants were able to talk about their eating behaviors and those of their families, the factors influencing those behaviors, their dietary knowledge and skills, and their reflections on their diet using the photographs. PE proved to be a feasible research technique for the studied population, and was well received and enjoyed by the participants. The participants perceived a few barriers with PE, such as forgetting to take pictures or not having ideas for new pictures. Nevertheless, PE allowed researchers to obtain rich information about eating behaviors, and can therefore be a useful method for working with populations of underserved areas. The PE data that this study collected could be used to create or improve interventions promoting healthy eating within the studied population.

Discovery of potential protein biomarkers of lung adenocarcinoma in bronchoalveolar lavage fluid by SWATH MS data-independent acquisition and targeted data extraction.

UNLABELLED: Lung cancer currently ranks as the neoplasia with the highest global mortality rate. Although some improvements have been introduced in recent years, new advances in diagnosis are required in order to increase survival rates. New mildly invasive endoscopy-based diagnostic techniques include the collection of bronchoalveolar lavage fluid (BALF), which is discarded after using a portion of the fluid for standard pathological procedures. BALF proteomic analysis can contribute to clinical practice with more sensitive biomarkers, and can complement cytohistological studies by aiding in the diagnosis, prognosis, and subtyping of lung cancer, as well as the monitoring of treatment response. The range of quantitative proteomics methodologies used for biomarker discovery is currently being broadened with the introduction of data-independent acquisition (DIA) analysis-related approaches that address the massive quantitation of the components of a proteome. Here we report for the first time a DIA-based quantitative proteomics study using BALF as the source for the discovery of potential lung cancer biomarkers. The results have been encouraging in terms of the number of identified and quantified proteins. A panel of candidate protein biomarkers for adenocarcinoma in BALF is reported; this points to the activation of the complement network as being strongly over-represented and suggests this pathway as a potential target for lung cancer research. In addition, the results reported for haptoglobin, complement C4-A, and glutathione S-transferase pi are consistent with previous studies, which indicates that these proteins deserve further consideration as potential lung cancer biomarkers in BALF. Our study demonstrates that the analysis of BALF proteins by liquid chromatography-tandem mass spectrometry (LC-MS/MS), combining a simple sample pre-treatment and SWATH DIA MS, is a useful method for the discovery of potential lung cancer biomarkers. SIGNIFICANCE: Bronchoalveolar lavage fluid (BALF) analysis can contribute to clinical practice with more sensitive biomarkers, thus complementing cytohistological studies in order to aid in the diagnosis, prognosis, and subtyping of lung cancer, as well as the monitoring of treatment response. Here we report a panel of candidate protein biomarkers for adenocarcinoma in BALF. Forty-four proteins showed a fold-change higher than 3.75 among adenocarcinoma patients compared with controls. This report is the first DIA-based quantitative proteomics study to use bronchoalveolar lavage fluid (BALF) as a matrix for discovering potential biomarkers. The results are encouraging in terms of the number of identified and quantified proteins, demonstrating that the analysis of BALF proteins by a SWATH approach is a useful method for the discovery of potential biomarkers of pulmonary diseases.

Ability of procalcitonin to predict bacterial meningitis in the emergency department.

INTRODUCTION: The aim of this study was to analyse and compare procalcitonin (PCT) and C-reactive protein (CRP) as tools for detecting bacterial meningitis and predicting bacteraemia. METHODS: Prospective, observational, and descriptive analytical study of 98 consecutive patients aged ≥15 years and diagnosed with acute meningitis in an emergency department between August 2009 and July 2013. RESULTS: We analysed 98 patients with AM (66 males [67%]); mean age was 44±21 years. The diagnosis was bacterial meningitis in 38 patients (20 with bacteraemia); viral meningitis in 33; probable viral meningitis in 15; and presumptively diagnosed partially treated acute meningitis in 12. PCT had the highest area under the ROC curve (AUC) (0.996; 95% CI, 0.987-1; p<0.001). With a cutoff of ≥ 0.74 ng/ml, PCT achieved 94.7% sensitivity, 100% specificity, negative predictive value (NPV) of 93.9%, and positive predictive value (PPV) of 100%. The mean levels for PCT were11.47±7.76 ng/ml in bacterial meningitis vs. 0.10±0.15 ng/ml in viral meningitis (p <0.001). The AUC for CRP was 0.916 and a cutoff of ≥ 90 mg/L achieved 67.5% sensitivity, 86.3% specificity, PPV of 89.2%, and NPV of 90.4%. As a predictor of bacteraemia in bacterial meningitis, only PCT delivered a significant difference (14.7±7.1 ng/mL vs. 4.68±3.54 ng/mL, p<0.001). A cutoff of ≥ 1.1 ng/mL achieved 94.6% sensitivity, 72.4% specificity, NPV of 95.4%, and PPV of 69.2%; the AUC was 0.965 (95% CI, 0.921-1; p<0.001). CONCLUSIONS: PCT has a high diagnostic power for acute meningitis in emergency department patients. PCT outperforms CRP in the detection of bacterial aetiology and is a good predictor of bacteraemia in bacterial meningitis.

Usefulness of procalcitonin and C-reactive protein for predicting bacteremia in urinary tract infections in the emergency department.

INTRODUCTION: The aim of this study was to analyze and compare the capacity of procalcitonin (PCT), C-reactive protein (CRP), lactate and leukocytes to predict the presence of bacteremia in patients with urinary tract infections (UTIs). METHODS: Observational, retro-prospective analytical study of adult patients (≥15 years) diagnosed with UTI in an emergency department from August 2012 to January 2013. RESULTS: The study included 328 patients diagnosed with UTI, with a mean age of 52±22 years, 74% of whom were women. Of these, 43 (13.1%) had bacteremia. For predicting bacteremia, PCT achieved the largest area under the receiver operating characteristic curve (ROC-AUC) at .993 (95% CI .987-1; P<.001). A cutoff≥1.16ng/mL achieves a sensitivity of 100%, a specificity of 97%, a positive predictive value of 84% and a negative predictive value of 100%. Lactate achieved an ROC-AUC of .844, and CRP achieved only .534. The mean values when comparing PCT levels in patients with UTIs with and without bacteremia were 8.08±16.37 and .34±.37ng/mL, respectively (P<.001). CONCLUSIONS: For patients with UTIs in the emergency department, PCT achieves considerable diagnostic performance for suspecting bacteremia, a performance greater than that of lactate, CRP and leukocytes.

Comparison of protein expression profiles between three Perkinsus spp., protozoan parasites of molluscs, through 2D electrophoresis and mass spectrometry.

The genus Perkinsus includes protozoan parasites of a wide range of marine molluscs worldwide, some of which have been responsible for heavy mollusc mortalities and dramatic economic losses. This study was performed with the aim of increasing the knowledge of Perkinsus spp. proteome. Proteins extracted from in vitro cultured cells of three species of this genus, P. marinus, P. olseni and P. chesapeaki, were analysed using 2D electrophoresis. Four gels from each species were produced. Qualitative and quantitative comparisons among gels were performed with Proteamweaver software. Cluster analysis grouped the four gels of each Perkinsus sp.; furthermore, P. marinus and P. olseni gels were grouped in a cluster different from P. chesapeaki. Around 2000 spots of each species were considered, from which 213 spots were common to the 3 species; P. chesapeaki and P. marinus shared 310 spots, P. chesapeaki and P. olseni shared 315 spots and P. marinus and P. olseni shared 242 spots. A number of spots were exclusive of each Perkinsus species: 1161 spots were exclusive of P. chesapeaki, 1124 of P. olseni and 895 of P. marinus. A total of 84 spots, including common and species-specific ones, were excised from the gels and analysed using MALDI-TOF and nESI-IT (MS/MS) techniques. Forty-two spots were successfully sequenced, from which 28 were annotated, most of them clustered into electron transport, oxidative stress and detoxification, protein synthesis, carbohydrate metabolism, signal transduction, metabolic process and proteolysis.

Blinking effect and the use of quantum dots in single molecule spectroscopy.

Luminescent semiconductor nanocrystals (quantum dots, QD) have unique photo-physical properties: high photostability, brightness and narrow size-tunable fluorescence spectra. Due to their unique properties, QD-based single molecule studies have become increasingly more popular during the last years. However QDs show a strong blinking effect (random and intermittent light emission), which may limit their use in single molecule fluorescence studies. QD blinking has been widely studied and some hypotheses have been done to explain this effect. Here we summarise what is known about the blinking effect in QDs, how this phenomenon may affect single molecule studies and, on the other hand, how the "on"/"off" states can be exploited in diverse experimental settings. In addition, we present results showing that site-directed binding of QD to cysteine residues of proteins reduces the blinking effect. This option opens a new possibility of using QDs to study protein-protein interactions and dynamics by single molecule fluorescence without modifying the chemical composition of the solution or the QD surface.

Association of topical amphotericin B lipid complex treatment to standard therapy for rhinomaxillary mucormycosis after liver transplantation: a case report.

Solid organ transplantation is becoming increasingly more common in the treatment of end-stage organ failure. The advent of newer immunosuppressive protocols and refined surgical techniques has allowed therapy to become standard care. Infection is a major and frequently life-threatening complication after transplantation and the incidence of opportunistic fungal infections in organ transplant recipients ranges from 2%-50% depending on the type of organ transplanted. We present a case of rhinomaxillary form of mucormycosis infection after liver transplantation. The succession of multiple risk factors in a torpid postoperative period was a key factor in the development of this disease. Multidisciplinary management with an early diagnosis, aggressive surgery, and intravenous and topical antifungal therapy care were definitive for the eradication of infection. The goal of the present report was to show efficacious management including the association of topical treatment with amphotericin B complex lipid to standard therapy and the absence of side effects.

Alterations to proteome and tissue recovery responses in fish liver caused by a short-term combination treatment with cadmium and benzo[a]pyrene.

The livers of soles (Solea senegalensis) injected with subacute doses of cadmium (Cd), benzo[a]pyrene (B[a]P), or their combination, were screened for alterations to cytosolic protein expression patterns, complemented by cytological and histological analyses. Cadmium and B[a]P, but not combined, induced hepatocyte apoptosis and Kupfer cell hyperplasia. Proteomics, however, suggested that apoptosis was triggered through distinct pathways. Cadmium and B[a]P caused upregulation of different anti-oxidative enzymes (peroxiredoxin and glutathione peroxidase, respectively) although co-exposure impaired induction. Similarly, apoptosis was inhibited by co-exposure, to which may have contributed a synergistic upregulation of tissue metalloproteinase inhibitor, beta-actin and a lipid transport protein. The regulation factors of nine out of eleven identified proteins of different types revealed antagonistic or synergistic effects between Cd and B[a]P at the prospected doses after 24 h of exposure. The results indicate that co-exposure to Cd and B[a]P may enhance toxicity by impairing specific responses and not through cumulative damage.

Propagation dynamics of optical vortices due to Gouy phase.

We study the propagation of off-axis vortices in a paraxial beam formed by two collinear Laguerre-Gauss beams. We show that the vortices move about the beam axis as the light propagates resulting in a rotation of the beam's transverse profile. This rotation is explained by the Gouy phase acquired by the component beams. Experimental measurements of the angular position of the vortices are in good agreement with a two-mode theory.

[Impact of the implementation of parenteral nutrition program by the clinical nutrition unit in surgical patients]. / Impacto de la introducción de un programa de nutrición parenteral por la unidad de nutrición clínica en pacientes quirúrgicos.

INTRODUCTION: The creation of a Nutrition Unit (NU), with a specialized professional establishing homogenous criteria and standardized proceedings for the use of parenteral nutrition (PN) may improve the clinical course of the patients and decrease the number of technique-related complications. OBJECTIVES: To describe the clinical characteristics of the patients submitted to PN at our Center. To assess the effect that the implementation of a NU has on the patients clinical course, and to know the frequency of mortality and hospital stay duration after the implementation of the NU at the University Hospital Complex of Albacete. MATERIAL AND METHODS: We reviewed the clinical charts of the patients receiving PN during the two years before and the two years after the creation of the NU by means of a two-period cohort study. RESULTS: Of the 390 patients, 100 belonged to the cohort before the NU and 290 to the following cohort. 61.3% of the patients were admitted at the surgery department. 25% of the patients had a personal history of digestive pathology. Among the reasons for ordering PN to the NU, surgical complications were the most common (66.7%). Oncologic abdominal surgery was the most common category (39.3%) out of the six in which the patients have been categorized. The mortality rate for the first cohort was 29% and for the second cohort 12.8% (p < 0,00). The average of stay days for the first cohort was 29.53 days and 27.67 days for the second one (p = 0.41). CONCLUSIONS: The implementation of a NU has a positive impact on the clinical course of hospitalized patients submitted to PN.