Accuracy of hospital-based surveillance systems for surgical site infection after adult spine surgery: a Bayesian latent class analysis.

BACKGROUND: Surgical site infections (SSIs) of the spine are morbid and costly complications. An accurate surveillance system is required to properly describe the disease burden and the impact of interventions that mitigate SSI risk. Unfortunately, uniform approaches to conducting SSI surveillance are lacking because of varying SSI case definitions, the lack of a perfect reference case definition and heterogeneous data sources. AIM: To assess the accuracy of four independent data sources that capture SSIs after spine surgery, with estimation of a measurement-error-adjusted SSI incidence. METHODS: A Bayesian latent class model assessed the sensitivity/specificity of each data source to identify SSI and to estimate a measurement-error-adjusted incidence. The four data sources used were: the discharge abstract database (DAD), the National Surgical Quality Improvement Program (NSQIP) database, the Infection Prevention and Control Canada (IPAC) database, and the Spine Adverse Events Severity database. FINDINGS: A total of 904 patients underwent spine surgery in 2017. The most sensitive data source was DAD (0.799; 95% credible interval (CrI): 0.597-0.943); the least sensitive was NSQIP (0.497; 95% CrI: 0.308-0.694). The most specific data source was IPAC (0.997; 95% CrI: 0.993-1.000) and the least specific was DAD (0.969; 95% CrI: 0.956-0.981). The measurement-error-adjusted SSI incidence was 0.030 (95% CrI: 0.019-0.045). The crude incidence using the DAD overestimated the incidence, and the three other data sources underestimated it. CONCLUSION: SSI surveillance in the spine surgery population is feasible using several data sources, provided that measurement error is considered.

Pre-treatment expectations of patients with spinal metastases: what do we know and what can we learn from other disciplines? A systematic review of qualitative studies.

BACKGROUND: Little is known about treatment expectations of patients with spinal metastases undergoing radiotherapy and/or surgery. Assuming that patients with spinal metastases share characteristics with patients who had spinal surgery for non-cancer related conditions and with advanced cancer patients, we performed a systematic review to summarize the literature on patient expectations regarding treatment outcomes of spinal surgery and advanced cancer care. METHODS: A comprehensive search was performed in MEDLINE, EMBASE and PsycINFO for studies between 2000 and sep-2019. Studies including adult patients (> 18 years), undergoing spinal surgery or receiving advanced cancer care, investigating patients' pre-treatment expectations regarding treatment outcomes were included. Two independent reviewers screened titles, abstracts and full-texts, extracted data and assessed methodological quality. RESULTS: The search identified 7343 articles, of which 92 were selected for full-text review. For this review, 31 articles were included. Patients undergoing spinal surgery had overly optimistic expectations regarding pain and symptom relief, they underestimated the probability of functional disability, and overestimated the probability of (complete) recovery and return to work. Studies highlighted that patients feel not adequately prepared for surgery in terms of post-treatment expectations. Similarly, advanced cancer patients receiving palliative treatment often had overly optimistic expectations regarding their survival probability and cure rates. CONCLUSIONS: Patients tend to have overly optimistic expectations regarding pain and symptom relief, recovery and prognosis following spinal surgery or advanced cancer care. Pretreatment consultation about the expected pain and symptom relief, recovery and prognosis may improve understanding of prognosis, and promote and manage expectations, which, in turn, may lead to better perceived outcomes. TRIAL REGISTRATION: PROSPERO registration number: CRD42020145151 .

Novel mRNA isoforms and mutations of uridine monophosphate synthetase and 5-fluorouracil resistance in colorectal cancer.

The drug fluorouracil (5-FU) is a widely used antimetabolite chemotherapy in the treatment of colorectal cancer. The gene uridine monophosphate synthetase (UMPS) is thought to be primarily responsible for conversion of 5-FU to active anticancer metabolites in tumor cells. Mutation or aberrant expression of UMPS may contribute to 5-FU resistance during treatment. We undertook a characterization of UMPS mRNA isoform expression and sequence variation in 5-FU-resistant cell lines and drug-naive or -exposed primary and metastatic tumors. We observed reciprocal differential expression of two UMPS isoforms in a colorectal cancer cell line with acquired 5-FU resistance relative to the 5-FU-sensitive cell line from which it was derived. A novel isoform arising as a consequence of exon skipping was increased in abundance in resistant cells. The underlying mechanism responsible for this shift in isoform expression was determined to be a heterozygous splice site mutation acquired in the resistant cell line. We developed sequencing and expression assays to specifically detect alternative UMPS isoforms and used these to determine that UMPS was recurrently disrupted by mutations and aberrant splicing in additional 5-FU-resistant colorectal cancer cell lines and colorectal tumors. The observed mutations, aberrant splicing and downregulation of UMPS represent novel mechanisms for acquired 5-FU resistance in colorectal cancer.

BCL2 mutations in diffuse large B-cell lymphoma.

BCL2 is deregulated in diffuse large B-cell lymphoma (DLBCL) by the t(14;18) translocation, gene amplification and/or nuclear factor-κB signaling. RNA-seq data have recently shown that BCL2 is the most highly mutated gene in germinal center B-cell (GCB) DLBCL. We have sequenced BCL2 in 298 primary DLBCL biopsies, 131 additional non-Hodgkin lymphoma biopsies, 24 DLBCL cell lines and 51 germline DNAs. We found frequent BCL2 mutations in follicular lymphoma (FL) and GCB DLBCL, but low levels of BCL2 mutations in activated B-cell DLBCL, mantle cell lymphoma, small lymphocytic leukemia and peripheral T-cell lymphoma. We found no BCL2 mutations in GC centroblasts. Many mutations were non-synonymous; they were preferentially located in the flexible loop domain, with few in BCL2-homology domains. An elevated transition/transversions ratio supports that the mutations result from somatic hypermutation. BCL2 translocations correlate with, and are likely important in acquisition of, additional BCL2 mutations in GCB DLBCL and FL. DLBCL mutations were not independently associated with survival. Although previous studies of BCL2 mutations in FL have reported mutations to result in pseudo-negative BCL2 protein expression, we find this rare in de-novo DLBCL.

Diagnóstico precoz de enfermedades pulmonares por tabaquismo / Early diagnose of smoking lung diseases

El tabaquismo es una epidemia y en Chile la prevalencia no ha disminuido. Entre las causas más importantes de muerte por tabaquismo están el cáncer pulmonar y la enfermedad pulmonar obstructiva crónica (EPOC). La erradicación del tabaquismo es la mejor estrategia de prevención de estas enfermedades. La segunda estrategia es la detección precoz de ellas. Sin embargo la EPOC está sub diagnosticada en todo el mundo. No está claro si la solución es hacer más espirometrías en población de riesgo. Es posible que otros métodos diagnósticos como la tomografía axial computada de tórax (TAC) y la difusión pulmonar, puedan mejorar la capacidad de diagnóstico precoz de esta enfermedad. El cáncer pulmonar es el más mortal de los cánceres. El diagnóstico en etapas tempranas mejora significativamente su pronóstico. Hay varios estudios en curso que evalúan el beneficio de hacer pesquisa de cáncer pulmonar con TAC

Cigarette smoking is worldwide epidemic and in Chile its prevalence is not decreasing. Lung cancer and COPD are important causes of smoking related mortality. Primary prevention of smoking is the best way to avoid these diseases. The second best strategy is an early detection of them. However COPD is under diagnosed all over the world and it is not clear if the solution is doing spirometry in risk population. CT scan of the chest and DLCO could increase the early diagnose. Lung cancer is a deadly disease. Its prognosis is much better in early stages. Currently there are some studies in progress evaluating the benefit of doing screening for lung cancer with CT of the chest

[Clinical features of adults younger and older than 50 years hospitalized with influenza A H1N1 2009 in a private hospital in Santiago, Chile]. / Caracterización clínica de adultos menores y mayores de 50 años hospitalizados por influenza A H1N1 2009 en un centro hospitalario privado en Santiago, Chile.

INTRODUCTION: The new pandemic influenza A H1N1 2009 virus has shown a different clinical behavior in different age groups. OBJECTIVE: To describe the clinical features of adult patients hospitalized with influenza AH1N1 2009 and compare the clinical and demographic variables among adults < 50 years and over 50 years old. PATIENTS AND METHOD: We included hospitalized patients between May 17 and July 17, 2009 confirmed by polymerase chain reaction (PCR) and/or rapid test for influenza A. RESULTS: 124 patients were hospitalized with a median age of 33 years (range: 15-82 years). 36% had comorbidities and the main symptoms were fever, cough, myalgia and sore throat. There were 16 cases with pneumonia. From 124 patients, 77% were < 50 and 23% > or = 50, [corrected] with comorbidity of 21% and 86%, respectively. There were no fatalities. CONCLUSIONS: Hospitalized patients had mild to moderate disease, a benign course and short hospitalization stay. There were more hospitalizations in A-49 and higher comorbidity in A-50.

Caracterización clínica de adultos menores y mayores de 50 años hospitalizados por influenza A H1N1 2009 en un centro hospitalario privado en Santiago, Chile / Clinical features of adults younger and older than 50 years hospitalized with influenza A H1N1 2009 in a private hospital in Santiago, Chile

Introduction: The new pandemic influenza A H1N1 2009 virus has shown a different clinical behavior in different age groups. Objective: To describe the clinical features of adult patients hospitalized with influenza AH1N1 2009 and compare the clinical and demographic variables among adults < 50 years and over 50 years old. Patients and Method: We included hospitalized patients between May 17 and July 17, 2009 confirmed by polymerase chain reaction (PCR) and/or rapid test for influenza A. Results: 124 patients were hospitalized with a median age of 33 years (range: 15-82 years). 36 percent had comorbidities and the main symptoms were fever, cough, myalgia and sore throat. There were 16 cases with pneumonia. From 124 patients, 77 percent were A-49 and 23 percentA-50, with comorbidity of 21 percent and 86 percent, respectively. There were no fatalities. Conclusions: Hospitalized patients had mild to moderate disease, a benign course and short hospitalization stay. There were more hospitalizations in A-49 and higher comorbidity in A-50.

Introducción: El nuevo virus influenza AH1N1 2009 ha mostrado un comportamiento clínico diferente en distintos grupos etáreos. Objetivo: Describir las características clínicas de los pacientes adultos hospitalizados con influenza A H1N1 2009 y comparar las variables clínicas y demográficas entre menores y mayores de 50 años. Pacientes y Método: Se incluyeron los pacientes hospitalizados entre el 17 de mayo y 17 de julio del 2009 confirmados por reacción de polimerasa en cadena (RPC) y/o pruebas rápidas para influenza A. Resultados: Se hospitalizaron 124 pacientes con una mediana de edad de 33 años (rango: 15-82 años). Un 36 por ciento presentó co-morbilidad y los síntomas principales fueron: fiebre, tos, mialgias y odinofagia. Hubo 16 casos con neumonía. Del total, 77 por ciento fueron < 50 y 23 por ciento ≥ 50 años. Tenían co-morbilidades 21 por ciento en el grupo < 50 versus 86 por ciento en ≥ 50 años. No hubo casos fatales. Conclusiones: Los pacientes presentaron una enfermedad leve a moderada, de curso benigno y corta hospitalización. Hubo más hospitalizados en < 50 y mayor co-morbilidad en ≥ 50 años.

Obliquity-paced Pliocene West Antarctic ice sheet oscillations.

Thirty years after oxygen isotope records from microfossils deposited in ocean sediments confirmed the hypothesis that variations in the Earth's orbital geometry control the ice ages, fundamental questions remain over the response of the Antarctic ice sheets to orbital cycles. Furthermore, an understanding of the behaviour of the marine-based West Antarctic ice sheet (WAIS) during the 'warmer-than-present' early-Pliocene epoch ( approximately 5-3 Myr ago) is needed to better constrain the possible range of ice-sheet behaviour in the context of future global warming. Here we present a marine glacial record from the upper 600 m of the AND-1B sediment core recovered from beneath the northwest part of the Ross ice shelf by the ANDRILL programme and demonstrate well-dated, approximately 40-kyr cyclic variations in ice-sheet extent linked to cycles in insolation influenced by changes in the Earth's axial tilt (obliquity) during the Pliocene. Our data provide direct evidence for orbitally induced oscillations in the WAIS, which periodically collapsed, resulting in a switch from grounded ice, or ice shelves, to open waters in the Ross embayment when planetary temperatures were up to approximately 3 degrees C warmer than today and atmospheric CO(2) concentration was as high as approximately 400 p.p.m.v. (refs 5, 6). The evidence is consistent with a new ice-sheet/ice-shelf model that simulates fluctuations in Antarctic ice volume of up to +7 m in equivalent sea level associated with the loss of the WAIS and up to +3 m in equivalent sea level from the East Antarctic ice sheet, in response to ocean-induced melting paced by obliquity. During interglacial times, diatomaceous sediments indicate high surface-water productivity, minimal summer sea ice and air temperatures above freezing, suggesting an additional influence of surface melt under conditions of elevated CO(2).

High-resolution three-dimensional tomographic diffractive microscopy of transparent inorganic and biological samples.

We have developed a tomographic diffractive microscope, equipped with a fluorescence confocal scanner. We measure experimentally the lateral resolution using an edge method and by comparing tomographic images of the same samples with wide-field and laser scanning confocal microscopy images; a scanning electron microscope image serves as a reference. The experimental resolution is shown to be to about 130 nm, or lambda/(3.5 NA). This instrument also permits one to measure 3D, complex index of refraction distributions, a quantity that is not accessible to conventional microscopes, and we show how this feature may be used to observe KCl crystals, absorption of which is very weak.

Accuracy of implanted port placement with the use of the electromagnetic CathTrack catheter locator system.

PURPOSE: To test whether an electromagnetic guidance system such as CathTrack would allow long-term central venous access devices to be reliably placed at a decreased cost and without radiation exposure to patients and staff. The following study was undertaken to verify accuracy of the CathTrack system for catheter placement and to develop guidelines for its use. METHODS: Twenty-nine consecutive patients were prospectively enrolled in the study and taken to the operating room for implantation of a permanent central venous access port. By protocol, the CathTrack system was used to guide initial catheter positioning using the center of the third intercostal space along the right sternal border as the desired external target. Fluoroscopy was then used to visualize tip position and relocate the catheter tip to the exact position desired by the surgeon. RESULTS: Catheter placement using the CathTrack system was successfully accomplished in 27 out of 29 patients. In two instances CathTrack was abandoned and fluoroscopy utilized because of difficulty in threading the initial guidewire into the superior vena cava. CONCLUSION: The CathTrack electromagnetic locator system can be used to reliably position catheters for the establishment of long-term central venous access. Decreased cost and elimination of radiation exposure are distinct advantages of this system over fluoroscopy.

A new approach to gas field ion sources.

A new approach to gas field ion sources is described. It is based on a structure made by inserting a field emission tip inside a small diameter tube. The tube supplies gas to the tip from a high-pressure chamber into a high-vacuum chamber where ionization takes place. Comparison of projection electron and ion micrographs shows that ionization results from a field ionization process taking place at the very end of the tip. Emission currents in the 10nA range, for a few kV emission voltages, are obtained with various gases including neon, air and hydrogen. Lifetime experiments with H(2) show stable emission for days.

Mandelic acid condensation polymer: novel candidate microbicide for prevention of human immunodeficiency virus and herpes simplex virus entry.

Presently marketed vaginal barrier methods are cytotoxic and damaging to the vaginal epithelium and natural vaginal flora when used frequently. Novel noncytotoxic agents are needed to protect men and women from sexually transmitted diseases. One novel candidate is a mandelic acid condensation polymer, designated SAMMA. The spectrum and mechanism of antiviral activity were explored using clinical isolates and laboratory-adapted strains of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). SAMMA is highly effective against all CCR5 and CXCR4 isolates of HIV in primary human macrophages and peripheral blood mononuclear cells. SAMMA also inhibits infection of cervical epithelial cells by HSV. Moreover, it exhibits little or no cytotoxicity and has an excellent selectivity index. SAMMA, although not a sulfonated or sulfated polymer, blocks the binding of HIV and HSV to cells by targeting the envelope glycoproteins gp120 and gB-2, respectively, and also inhibits HSV entry postattachment. SAMMA is an excellent, structurally novel candidate microbicide that warrants further preclinical evaluation.

Conducting, semiconducting and insulating objects observed by low-energy electron holography.

To demonstrate the potential of low energy in line projection holography, we study the reconstruction of the experimental holograms of three electrically different objects: a conducting, a semiconducting and an insulating object. The reconstructions of these holograms provide meaningful results for a large range of magnification of the object. The comparison between the reconstructed images and the scanning electron microscopy (SEM) micrographs of the same objects shows that the shapes and the dimensions of the reconstructed objects are identical to those obtained by conventional SEM. So, the simple assumptions needed to the reconstruction are justified. The reconstructions show a 2 nm resolution and appear superior than the best obtained SEM micrographs, when available. We also show some limitations of the reconstruction process. We point out that both numerical artifacts and experimental conditions are responsible for these limitations.

Improved low energy electron projection in-line holograms reconstruction: application to the holograms of a tungsten tip.

A modification of the classical calculation algorithm is presented which allows to minimize the effect of the long range oscillations created by the twin object in the reconstruction process of in-line holograms obtained by low energy electron projection microscopy. The reconstructed shapes of a tungsten tip, observed with different magnifications are shown.

Inconsistent link between low-frequency oscillations: R-R interval responses to augmented Mayer waves.

Low-frequency oscillations in arterial blood pressure (Mayer waves) and R-R interval are thought to be linked through the arterial baroreflex. To delve into this relationship, we applied low (10 mmHg) and moderate (30 mmHg) lower body negative pressure (LBNP) in 10-s cycles to 18 healthy young male subjects. They showed no change in average blood pressure with this oscillatory stimulus but did show a significant decrease in R-R interval (P < 0.05) during both levels of LBNP. In addition, we succeeded in augmenting low-frequency blood pressure oscillations in a graded response to oscillatory LBNP level (P < 0.05) while significantly increasing low-frequency R-R interval oscillations (P < 0.05). However, cross-spectral coherence between these increased oscillations was highly variable across individuals and stimulus level. Although nearly all subjects showed significant coherence during basal conditions (n = 17), only seven subjects maintained significant coherence during both levels of LBNP. These results suggest that a complex interaction of regulatory mechanisms determines the link between low-frequency oscillations and the responses to even low levels of LBNP.

[Emotional, physical and social consequences of breast cancer: viability and utilization of a clinical questionnaire]. / Conséquences émotionnelles, physiques et sociales du dépistage du cancer du sein: fiabilité et utilisation d'un questionnaire clinique.

The aim of this study was to evaluate the reliability of a French Canadian version of the "Psychological Consequences Questionnaire" (PCQ) among 306 Quebec women between the ages of 50 and 69. The internal consistencies of the emotional, physical and social dimensions are respectively 0.91, 0.86 and 0.72 (Cronbach's alpha). The temporal stability was greater than 68% for each question. Meanwhile, analysis showed that 4 of the 12 questions were highly predictive of the results of the whole questionnaire (R2 = 0.91). In addition, these 4 questions are in concordance with the diagnostic criteria for adaptive disorder, anxiety disorder and general anxiety. The French Canadian version of PCQ was found to be easy to use and reliable. We would suggest a shorter version of the questionnaire, including only four questions. This version would be even easier to use and more effective to control the emotional, physical and social consequences over the different stages of breast cancer screening.

Imaging charged objects using low-energy-electron coherent beams.

The microscopic shapes, unobservable by conventional electron optics, of objects surrounded by electrostatic fields are observed. The method directly uses electron-coherent-beam imaging concepts and is successfully applied to recently developed low-energy-electron projection holography. Experimental demonstrations on objects charged in a controlled way like a biased metallic tip as well as on a self-charging insulator object are shown.

The filmless radiology reading room: a survey of established picture archiving and communication system sites.

The purpose of this study was to survey radiologists experienced in soft-copy diagnosis using computer workstations about their current reading room environment, their impressions of the efficacy of their reading room design, and their recommendations based on their experience for improvement of the soft-copy reading environment. Surveys were obtained from radiologists at seven sites representing three major picture archiving and communication system (PACS) vendors throughout the world that have had extensive experience with soft-copy interpretation of radiology studies. The radiologists filled out a detailed survey, which was designed to assess their current reading room environment and to provide them with the opportunity to make suggestions about improvement of the PACS reading rooms. The survey data were entered into a database and results were correlated with multiple parameters, including experience with PACS, types of modalities interpreted on the system, and number of years of experience in radiology. The factors judged to be most important in promoting radiologist productivity were room lighting, monitor number, and monitor brightness. Almost all of the radiologists indicated that their lighting source was from overhead rather than indirect or portable light sources. Approximately half indicated they had the capability of dimming the brightness of the overhead lighting. Most radiologists indicated that they were able to adjust room temperature but that they did not have individual temperature controls at their workstations. The radiologists indicated that the most troublesome sources of noise included background noise, other radiologists, and clinicians much more than noise from computer monitors, technologists, or patients. Most radiologists did not have chairs that could recline or arm rests. Most did have wheels and the capability to swivel, both of which were judged important. The majority of chairs also had lumbar support, which was also seen to be important. Radiologists commonly adjusted room lighting and their reading chair, but rarely adjusted room temperature or monitor brightness. The median number of hours spent at the workstation before taken a "break" was 1.5. Common recommendations to improve the room layout included compartmentalization of the reading room and availability of the hospital/radiology information system at each workstation. The survey data suggest several areas of potential improvement based on radiologists' experience. Optimization of soft-copy reading room design is likely to result in decreased fatigue and increased productivity.