How do patients and care partners describe diagnostic uncertainty in an emergency department or urgent care setting?

OBJECTIVES

Little is known about how patients perceive diagnostic uncertainty. We sought to understand how patients and care partners perceive uncertainty in an emergency or urgent care setting, where making a final diagnosis is often not possible.

METHODS

We administered a survey to a nationally representative panel on patient-reported diagnostic excellence in an emergency department or urgent care setting. The survey included items specific to perceived diagnostic excellence, visit characteristics, and demographics. We analyzed responses to two open-ended questions among those who reported uncertainty in the explanation they were given. Themes were identified using an inductive approach, and compared by whether respondents agreed or disagreed the explanation they were given was true.

RESULTS

Of the 1,116 respondents, 106 (10 %) reported that the care team was not certain in the explanation of their health problem. Five themes were identified in the open-ended responses: poor communication (73 %), uncertainty made transparent (10 %), incorrect information provided (9 %), inadequate testing equipment (4 %), and unable to determine (4 %). Of the respondents who reported uncertainty, 21 % (n=22/106) reported the explanation of their problem given was not true.

CONCLUSIONS

The findings of this analysis suggest that the majority of patients and their care partners do not equate uncertainty with a wrong explanation of their health problem, and that poor communication was the most commonly cited reason for perceived uncertainty.

Patient Reasoning: Patients' and Care Partners' Perceptions of Diagnostic Accuracy in Emergency Care

OBJECTIVES

In the context of validating a measure of patient report specific to diagnostic accuracy in emergency department or urgent care, this study investigates patients' and care partners' perceptions of diagnoses as accurate and explores variations in how they reason while they assess accuracy.

METHODS

In February 2022, we surveyed a national panel of adults who had an emergency department or urgent care visit in the past month to test a patient-reported measure. As part of the survey validation, we asked for free-text responses about why the respondents indicated their (dis)agreement with 2 statements comprising patient-reported diagnostic accuracy: 1) the explanation they received of the health problem was true and 2) the explanation described what to expect of the health problem. Those paired free-text responses were qualitatively analyzed according to themes created inductively.

RESULTS

A total of 1,116 patients and care partners provided 982 responses coded into 10 themes, which were further grouped into 3 reasoning types. Almost one-third (32%) of respondents used only corroborative reasoning in assessing the accuracy of the health problem explanation (alignment of the explanation with either test results, patients' subsequent health trajectory, their medical knowledge, symptoms, or another doctor's opinion), 26% used only perception-based reasoning (perceptions of diagnostic process, uncertainty around the explanation received, or clinical team's attitudes), and 27% used both types of reasoning. The remaining 15% used general beliefs or nonexplicated logic (used only about accurate diagnoses) and combinations of general reasoning with perception-based and corroborative.

CONCLUSIONS

Patients and care partners used multifaceted reasoning in their assessment of diagnostic accuracy.

IMPLICATIONS

As health care shifts toward meaningful diagnostic co-production and shared decision making, in-depth understanding of variations in patient reasoning and mental models informs use in clinical practice.

HIGHLIGHTS

An analysis of 982 responses examined how patients and care partners reason about the accuracy of diagnoses they received in emergency or urgent care.In reasoning, people used their perception of the process and whether the diagnosis matched other factual information they have.We introduce "patient reasoning" in the diagnostic measurement context as an area of further research to inform diagnostic shared decision making and co-production of health.

Various tomato cultivars display contrasting morphological and molecular responses to a chronic heat stress

Climate change is one of the biggest threats that human society currently needs to face. Heat waves associated with global warming negatively affect plant growth and development and will increase in intensity and frequency in the coming years. Tomato is one of the most produced and consumed fruit in the world but remarkable yield losses occur every year due to the sensitivity of many cultivars to heat stress (HS). New insights into how tomato plants are responding to HS will contribute to the development of cultivars with high yields under harsh temperature conditions. In this study, the analysis of microsporogenesis and pollen germination rate of eleven tomato cultivars after exposure to a chronic HS revealed differences between genotypes. Pollen development was either delayed and/or desynchronized by HS depending on the cultivar considered. In addition, except for two, pollen germination was abolished by HS in all cultivars. The transcriptome of floral buds at two developmental stages (tetrad and pollen floral buds) of five cultivars revealed common and specific molecular responses implemented by tomato cultivars to cope with chronic HS. These data provide valuable insights into the diversity of the genetic response of floral buds from different cultivars to HS and may contribute to the development of future climate resilient tomato varieties.

Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study

OBJECTIVE

To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America.

METHODS

A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square.

RESULTS

In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD.

CONCLUSIONS

In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

Impact of COVID-19 in pediatric oncology care in Latin America during the first year of the pandemic

BACKGROUND

The ongoing coronavirus 2019 disease (COVID-19) pandemic strained medical systems worldwide. We report on the impact on pediatric oncology care in Latin American (LATAM) during its first year.

METHOD

Four cross-sectional surveys were electronically distributed among pediatric onco-hematologists in April/June/October 2020, and April/2021 through the Latin American Society of Pediatric Oncology (SLAOP) email list and St Jude Global regional partners.

RESULTS

Four hundred fifty-three pediatric onco-hematologists from 20 countries responded to the first survey, with subsequent surveys response rates above 85%. More than 95% of participants reported that treatment continued without interruption for new and active ongoing patients, though with disruptions in treatment availability. During the first three surveys, respondents reported suspensions of outpatient procedures (54.2%), a decrease in oncologic surgeries (43.6%), radiotherapy (28.4%), stem cell transplants (SCT) (69.3%), and surveillance consultations (81.2%). Logistic regression analysis showed that at the beginning of the first wave, participants from countries with healthcare expenditure below 7% were more likely to report a decrease in outpatient procedures (odds ratio [OR]: 1.84, 95% CI: 1.19-2.8), surgeries (OR: 3, 95% CI: 1.9-4.6) and radiotherapy (OR: 6, 95% CI: 3.5-10.4). Suspension of surveillance consultations was higher in countries with COVID-19 case fatality rates above 2% (OR: 3, 95% CI: 1.4-6.2) and SCT suspensions in countries with COVID-19 incidence rate above 100 cases per 100,000 (OR: 3.48, 95% CI: 1.6-7.45). Paradoxically, at the beginning of the second wave with COVID-19 cases rising exponentially, most participants reported improvements in cancer services availability.

CONCLUSION

Our data show the medium-term collateral effects of the pandemic on pediatric oncology care in LATAM, which might help delineate oncology care delivery amid current and future challenges posed by the pandemic.

Accelerated artificial aging and color stability in resin-based cements

The aim of this study was to determine color change after accelerated artificial ageing (AAA) of different composite cements that are used with veneers. Five cylindrical test specimens, 15 mm in diameter and 2 mm thick, were made from a single layer of each of the following: RelyX Veneer 3M ESPE (RX), Paracore White Coltene (PC), Solocem White Opaque Coltene (SO), Resin Duo Cement Densell (DC), Panavia V5 Paste Kuraray Noritake (PA) and Panavia F2.0 Kuraray Noritake (PF) (30 specimens altogether). The specimens were light cured following manufacturers' instructions using a Coltolux LED (Coltene) unit. Initial color was determined using an Easyshade - Vita Zahnfabrik Spectrophotometer. Then, the specimens were subjected to AAA for two weeks (336 hours) with cycles of 4 hours of UV light at 60 °C and 4 hours of vapor condensation at 50 °C, successively, after which color was recorded again. Color change was determined for each specimen according to the differenceinshadeon the Vita scale before and after AAA. Results were analyzed using Kruskal Wallis test. Mean and standard deviation for each group were: RX 8.40 (1.52); PC 8.60 (3.13); SO 6.40 (3.51); DC 10.00 (0.00); PA 7.60 (3.29); PF 2.00 (0.00). The Kruskal Wallis test showed significant difference for material (p<0.05), and comparison of means showed difference between Panavia F2.0 and the other materials. A table providing equivalence between the Vita Classic and CIELAB scales was used to transfer the recorded colors to the CIELAB scale, and the color difference ΔE was calculated for each group, where ΔL, Δa and Δb are the differences in the L, a and b values before and after the AAA. The mean and standard deviation were analyzed statistically by the ANOVA test and Tukey's test. Mean and standard deviation for each group were: RX 14.94 (2.02); PC 14.51 (4.02); SO 12.08 (4.53); DC 16.31 (0.00); PA 10.9 (3.38); PF 7.24 (0.00). The ANOVA test showed significantdifferenceformaterial (p<0.05). Tukey's test showed two groups (PF-DC, RX, PA). Under the experimental conditions of this study, it can be concluded that accelerated ageing significantly affects the color stability of the resin based cements tested.

Physical activity trajectories are associated with the risk of all-cause and cardiovascular disease mortality in patients with coronary heart disease. A systematic review and meta-analysis

Background

Current guidelines recommend that adults with chronic health conditions should engage in regular physical activity (PA), and avoid inactivity. Yet, the exact role of PA trajectories in the mortality risk of patients with coronary heart disease (CHD) remains unclear.

Purpose

We aimed to perform a systematic review and meta-analysis on the association of longitudinal trajectories of PA with all-cause and cardiovascular disease (CVD) mortality in patients with CHD.

Methods

We performed a systematic review and meta-analysis based on PRISMA statement. Six electronic databases were searched for cohort studies that analysed the association of PA trajectories (inactive over time, active over time, increased activity over time, and decreased activity over time) with the risk of all-cause and CVD mortality in patients with CHD. Study quality was evaluated by the Newcastle Ottawa scale. We used the inverse variance weighted method to combine summary measures using random-effects models to minimize the effect of between-study heterogeneity. The study is registered in PROSPERO.

Results

We meta-analyzed nine longitudinal cohorts involving 33,576 patients (25010 acute CHD, 8566 chronic CHD, mean age 62.5 years, 34% women, median follow-up duration 7.2 years), according to four PA trajectories. All studies assessed PA through validated questionnaires. The definitions of activity and inactivity at baseline and follow-ups were in agreement with current PA guidelines. Trajectories were calculated based on comparison of activity status at baseline and follow-up. All the studies defined increased activity over time as moving from the inactive to the active category, and decreased activity over time as moving from the active to the inactive category. Compared to patients remaining inactive over time, the lowest risk of all-cause and CVD mortality was observed in patients remaining active over time (HR [95% CI]: 0.50 [0.39–0.63] and 0.48 [0.35–0.68], respectively), followed by patients who increased their PA over time (HR [95% CI]:0.55 [0.44–0.7] and 0.63 [0.51–0.78], respectively), and patients who decreased activity over time (HR [95% CI]: 0.80 [0.64–0.99] and 0.91 [0.67–1.24], respectively). These results were consistent both in the acute and chronic CHD settings. The overall risk of bias was low, and no evidence of publication bias was observed. Multiple sensitivity analyses provided consistent results.

Conclusions

In patients with CHD, the risk of all-cause and CVD mortality is progressively reduced from being inactive over time, to decreased activity over time, to increased activity over time, to being active over time. These findings highlight the benefits of adopting a more physically active lifestyle in patients with chronic and acute CHD, independent of previous PA levels. Future studies should clarify the complex interactions between motivations and disease severity as potential drivers for PA trajectories

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): University of Bern

Small RNAs as a New Platform for Tuning the Biosynthesis of Silver Nanoparticles for Enhanced Material and Functional Properties

Genetic engineering of nanoparticle biosynthesis in bacteria could help facilitate the production of nanoparticles with enhanced or desired properties. However, this process remains limited due to the lack of mechanistic knowledge regarding specific enzymes and other key biological factors. Herein, we report on the ability of small noncoding RNAs (sRNAs) to affect silver nanoparticle (AgNP) biosynthesis using the supernatant from the bacterium Deinococcus radiodurans. Deletion strains of 12 sRNAs potentially involved in the oxidative stress response were constructed, and the supernatants from these strains were screened for their effect on AgNP biosynthesis. We identified several sRNA deletions that drastically decreased AgNP yield compared to the wild-type (WT) strain, suggesting the importance of these sRNAs in AgNP biosynthesis. Furthermore, AgNPs biosynthesized using the supernatants from three of these sRNA deletion strains demonstrated significantly enhanced antimicrobial and catalytic activities against environmentally relevant dyes and bacteria relative to AgNPs biosynthesized using the WT strain. Characterization of these AgNPs using electron microscopy (EM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) revealed that the deletion of these small RNAs led to changes within the supernatant composition that altered AgNP properties such as the surface chemistry, surface potential, and overall composition. Taken together, our results demonstrate that modulating specific sRNA levels can affect the composition of supernatants used to biosynthesize AgNPs, resulting in AgNPs with unique material properties and improved functionality; as such, we introduce sRNAs as a new platform for genetically engineering the biosynthesis of metal nanoparticles using bacteria. Many of the sRNAs examined in this work have potential regulatory roles in oxidative stress responses; further studies into their targets could help provide insight into the specific molecular mechanisms underlying bacterial biosynthesis and metal reduction, enabling the production of nanoparticles with enhanced properties.

Reduced plasmablast frequency is associated with seronegative myasthenia gravis

BACKGROUND

The immunopathology of autoimmune seronegative myasthenia gravis (SN MG) is poorly understood. Our objective was to determine immune profiles associated with a diagnosis of SN MG.

METHODS

We performed high-dimensional flow cytometry on blood samples from SN MG patients (N = 68), healthy controls (N = 46), and acetylcholine receptor antibody (AChR+) MG patients (N = 27). We compared 12 immune cell subsets in SN MG to controls using logistic modeling via a discovery-replication design. An exploratory analysis fit a multinomial model comparing AChR+ MG and controls to SN MG.

RESULTS

An increase in CD19⁺ CD20^- CD38^hi plasmablast frequencies was associated with lower odds of being a SN MG case in both the discovery and replication analyses (discovery P-value = .0003, replication P-value = .0021). Interleukin (IL) -21 producing helper T cell frequencies were associated with a diagnosis of AChR+ MG (P = .004).

CONCLUSIONS

Reduced plasmablast frequencies are strongly associated with a SN MG diagnosis and may be a useful diagnostic biomarker in the future.

Macular Ganglion Cell and Inner Plexiform Layer Thickness Is More Strongly Associated With Visual Function in Multiple Sclerosis Than Bruch Membrane Opening-Minimum Rim Width or Peripapillary Retinal Nerve Fiber Layer Thicknesses

BACKGROUND

Optical coherence tomography (OCT) measurements of ganglion cell + inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses are associated with visual function (VF) and disability in multiple sclerosis (MS). However, the value of measuring Bruch membrane opening-minimum rim width (BMO-MRW) thickness in MS remains unclear.

METHODS

Sixty-eight patients with MS and 22 healthy controls (HCs) underwent spectral domain OCT, 100%-contrast visual acuity (VA), 2.5%- and 1.25%-contrast letter acuity (LA), and Expanded Disability Status Scale (EDSS) testing. Mixed-effects linear regression models, accounting for within-subject, intereye correlations, were used to assess relationships.

RESULTS

The MS cohort exhibited significantly lower BMO-MRW (P = 0.01), pRNFL at 3.7-, 4.1-, and 4.7-mm diameters surrounding the optic disc (P < 0.001 for all), and GCIPL (P < 0.001) thicknesses than HCs. BMO-MRW thickness was associated with 100%-VA (P < 0.001, R = 0.08), 2.5%-LA (P < 0.001; R = 0.13), and 1.25%-LA (P = 0.002; R = 0.11). All measured pRNFL thicknesses were associated with high- and low-contrast VF (all: P < 0.001). GCIPL thickness was more strongly associated with 100%-VA (P < 0.001; R = 0.23), 2.5%-LA (P < 0.001; R = 0.27), and 1.25%-LA (P < 0.001; R = 0.21) than the other OCT measures assessed. All OCT measures were significantly, but weakly, associated with EDSS scores.

CONCLUSIONS

BMO-MRW and pRNFL thicknesses are reduced and associated with VF and disability in MS, but GCIPL thickness is a stronger marker of visual impairment. Our findings corroborate the utility of OCT in providing valuable information regarding the MS disease process.

Parental Concerns of Underserved Young Children at Risk for Autism

Early identification of children at risk for autism spectrum disorder (ASD) is critical to promote optimal outcomes. However disparities in early recognition of ASD based on race, ethnicity, income, and English proficiency persist. Little is known regarding how parents from these groups describe concerns. The study aim was to understand how parents of children from underserved backgrounds at developmental risk describe concerns about child development and behavior. To address this gap, developmental concerns of 204 parents of children at-risk for ASD from underserved communities were analyzed. In this sample, the number and type of parental concerns differed based on parent primary language but not the presence of ASD or ethnicity. Parents whose primary language was Spanish were less likely to express concerns about their child's development or to express ASD-specific concerns. These findings have implications for how clinicians elicit and interpret developmental concerns from underserved families.

Image Artifacts in Optical Coherence Tomography Angiography Among Patients With Multiple Sclerosis

PURPOSE

To evaluate artifacts in optical coherence tomography angiography (OCT-A) images of multiple sclerosis (MS) patients and healthy controls.

MATERIALS AND METHODS

This was a prospective cross-sectional study conducted at the Department of Neurology and the Wilmer Eye Institute at Johns Hopkins Hospital. Subjects included patients with an established diagnosis of MS and healthy volunteers. OCT-A was performed using Spectralis® OCT-A prototype, OCT2 (Heidelberg, Germany). The type and frequency of artifacts, the clinical factors associated with them, and their impact on vessel density measurements were assessed.

RESULTS

Overall, 385 images from 102 participants were analyzed. The majority of images (97.1%) had some degree of artifact. The most frequent was motion artifact (96.3%), followed by blinking (51.9%), and loss of focus (25.1%). MS patients were more likely to have any artifact vs. controls (OR [95% CI], 3.83 [1.12-12.92]), and were more likely to have motion artifacts with longer disease duration (OR [95% CI], 1.11 [1.03-1.20]) or history of optic neuritis (OR [95% CI], 4.24 [1.19-15.16]). The relative area occupied by the artifact was found to underestimate vessel density measurements in both MS patients and controls.

CONCLUSIONS

Artifacts are common with OCT-A imaging using this particular Spectralis® OCT-A prototype and can impact quantitative vascular density metrics. Future studies should review images for artifacts before drawing definitive conclusions.

In vitro inactivation of Mycobacterium avium subsp. paratuberculosis (MAP) by use of copper ions

Background

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis, a contagious infectious disease that affects domestic and wild ruminants causing chronic inflammation of the intestine. MAP has proven to be very resistant to both physical and chemical processes, making it difficult to control this pathogen. Based on the recognized antimicrobial properties of copper, the objective of this study was to evaluate the effectiveness of copper ions to reduce MAP numbers and/or MAP viability in a fluid matrix. Besides, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli were used as controls of the effectiveness of copper ions. MAP-spiked PBS was subjected to copper ions treatment at 24 V for 5 min and the PBS suspensions were sampled before and after treatment. MAP viability and quantification were determined using three complementary techniques: a phage amplification assay, MGIT culture and qPCR.

Results

Moderate numbers (10³ CFU ml⁻¹) of the two control bacteria were completely eliminated by treatment with copper ions. For MAP, copper ions treatment reduced both the viability and numbers of this pathogen. Phage assay information quickly showed that copper ions (24 V for 5 min) resulted in a significant reduction in viable MAP. MGIT culture results over time showed statistically significant differences in time-to-detection (TTD) values between PRE and POST treatment. MAP genome equivalent estimates for PBS suspensions indicated that MAP numbers were lower in samples POST-treatment with copper ions than PRE-treatment.

Conclusions

The use of copper ions resulted in a significant reduction of MAP in a liquid matrix, although some MAP survival on some occasions was observed.

Particle swarm optimization of nanoantenna-based infrared detectors

The multi-resonant response of three-steps tapered dipole nano-antennas, coupled to a resistive and fast micro-bolometer, is investigated for the efficient sensing in the infrared band. The proposed devices are designed to operate at 10.6 μm, regime where the complex refractive index of metals becomes important, in contrast to the visible counterpart, and where a full parametric analysis is performed. By using a particle swarm algorithm (PSO) the geometry was adjusted to match the impedance between the nanoantenna and the micro-bolometer, reducing the return losses by a factor of 650%. This technique is compared to standards matching techniques based on transmission lines, showing better accuracy. Tapered dipoles therefore open the route towards an efficient energy transfer between load elements and resonant nanoantennas.

Induced ovule-to-flower switch by interfering with SlIMA activity in tomato

The INHIBITOR OF MERISTEM ACTIVITY in tomato (SlIMA) and MINI ZINC FINGER 2 in Arabidopsis (AtMIF2), two members of the MINI ZINC FINGER family (MIF), are involved in the regulation of flower and ovule development. MIF proteins possess a unique non-canonical zinc-finger domain that confers the capacity to interact with other protein partners. The characterization of SlIMA and AtMIF2 gain- and loss-of-function transgenic lines in Solanum lycopersicum and Arabidopsis thaliana respectively, allowed the demonstration of their conserved functional role in the termination of floral stem cell maintenance. During early floral development, the expression of SlIMA and AtMIF2 is induced by the MADS-Box transcription factor AGAMOUS (AG). Then, SlIMA or AtMIF2 protein recruits the C₂H₂ zinc finger KNUCKLES (KNU), in a transcriptional repressor complex together with TOPLESS (TPL) and HISTONE DEACETYLASE19 (HDA19). This complex binds to the WUSCHEL (WUS) locus leading to its repression. To further characterize the role of these interactions in flower development, we have investigated the effects of a dominant negative form of SlIMA, SlIMA^ch that leads to spectacular phenotypes, including ovule conversion into a floral meristem.

Posttransplant oxygen inhalation improves the outcome of subcutaneous islet transplantation: A promising clinical alternative to the conventional intrahepatic site

Subcutaneous tissue is a promising site for islet transplantation, due to its large area and accessibility, which allows minimally invasive procedures for transplantation, graft monitoring, and removal of malignancies as needed. However, relative to the conventional intrahepatic transplantation site, the subcutaneous site requires a large number of islets to achieve engraftment success and diabetes reversal, due to hypoxia and low vascularity. We report that the efficiency of subcutaneous islet transplantation in a Lewis rat model is significantly improved by treating recipients with inhaled 50% oxygen, in conjunction with prevascularization of the graft bed by agarose-basic fibroblast growth factor. Administration of 50% oxygen increased oxygen tension in the subcutaneous site to 140 mm Hg, compared to 45 mm Hg under ambient air. In vitro, islets cultured under 140 mm Hg oxygen showed reduced central necrosis and increased insulin release, compared to those maintained in 45 mm Hg oxygen. Six hundred syngeneic islets subcutaneously transplanted into the prevascularized graft bed reversed diabetes when combined with postoperative 50% oxygen inhalation for 3 days, a number comparable to that required for intrahepatic transplantation; in the absence of oxygen treatment, diabetes was not reversed. Thus, we show oxygen inhalation to be a simple and promising approach to successfully establishing subcutaneous islet transplantation.

Relevance of small GTPase Rac1 pathway in drug and radio-resistance mechanisms: Opportunities in cancer therapeutics

Rac1 GTPase signaling pathway has a critical role in the regulation of a plethora of cellular functions governing cancer cell behavior. Recently, it has been shown a critical role of Rac1 in the emergence of resistance mechanisms to cancer therapy. This review describes the current knowledge regarding Rac1 pathway deregulation and its association with chemoresistance, radioresistance, resistance to targeted therapies and immune evasion. This supports the idea that interfering Rac1 signaling pathway could be an interesting approach to tackle cancer resistance.

Rho GTPases as therapeutic targets in cancer (Review)

Rho GTPases are key molecular switches controlling the transduction of external signals to cytoplasmic and nuclear effectors. In the last few years, the development of genetic and pharmacological tools has allowed a more precise definition of the specific roles of Rho GTPases in cancer. The aim of the present review is to describe the cellular functions regulated by these proteins with focus in deregulated signals present in malignant tumors. Finally, we describe the state of the art in search of different experimental therapeutic strategies with Rho GTPases as molecular targets.

Prognostic severity scores for patients with COPD exacerbations attending emergency departments

SETTING

Reported predictors of the adverse evolution of patients with chronic obstructive pulmonary disease exacerbations (eCOPD) are various and inconsistent in the bibliography.

OBJECTIVE

To develop clinical prediction rules for short-term outcomes in eCOPD patients attending an emergency department (ED).

DESIGN

Prospective cohort study of patients with an eCOPD. Short-term outcomes were admission to an intensive care unit (ICU), admission to an intermediate respiratory care unit (IRCU) and death in these groups. Multivariate logistic regression models were developed for each of the outcomes.

RESULTS

Predictors of ICU or IRCU admission were use of long-term home oxygen therapy (LT-HOT) or non-invasive mechanical ventilation (NIMV), elevated PCO2 and decreased pH upon ED arrival (area under the curve [AUC] 0.87 in the derivation sample; 0.89 in the validation sample). Among those admitted to an ICU or IRCU, predictors of death were increased age, use at home of LT-HOT or NIMV, use of inspiratory accessory muscles upon ED arrival and altered Glasgow Coma Scale (<15 points) (AUC 0.78).

CONCLUSIONS

Three clinical predictors available in the ED can be used to create a simple score to predict the need for intensive treatment among eCOPD patients. Such a score can be a tool for clinical practice.

Sage (Salvia officinalis) and fennel (Foeniculum vulgare) improve cryopreserved boar epididymal semen quality study

The aim of this study was to evaluate the effect of fennel and sage extracts and the influence of the egg yolk source (fresh or pasteurized) on the success of freezing boar epididymal spermatozoa. In experiment 1, epididymal sperm was recovered by flushing and cryopreserved in a lactose-egg yolk solution supplemented with various concentrations (10, 5 and 2.5 g/L) of sage or fennel. Sperm quality was evaluated (motility, viability, HOST and acrosome integrity) at 0 h and 2 h after thawing. Fennel 10 g/L and sage 5 g/L and control (no extracts) were selected for experiment 2 which also compared fresh or pasteurized egg yolk in the freezing extender and measured DNA integrity of the frozen sperm. Results showed that the interaction between fennel and sage antioxidants with fresh egg yolk significantly improved post thaw sperm quality and protected boar epididymal spermatozoa from cryopreservation damage as a result of oxidative stress.

Relationship of sociodemographic variables with outcomes after cataract surgery

PURPOSE

The objective of this study is to analyse the relationship between sociodemographic characteristics of patients undergoing cataract extraction and their outcomes.

METHODS

The method comprised a prospective cohort study of patients recruited from 17 hospitals of different areas of Spain. Data gathered before surgery included sociodemographic variables, visual acuity, and visual function (using the Visual Function Index-14). After surgery, we assessed visual acuity and visual function at 6 weeks and at 3 months, respectively. Multivariate multilevel analysis was performed to assess the relationship of sociodemographic variables with changes in visual acuity and function, analysing whether improvements surpassed the minimal clinically important differences (MCIDs).

RESULTS

Multivariate analysis showed that for visual acuity, (i) older men had a lower odds ratio (OR) of surpassing the MCID (OR: 65-75 years, 0.64; >75 years, 0.51); (ii) those with primary (1.65) or secondary (1.41) education had higher ORs than those with no formal education; and (iii) those living in a residential home had a lower OR than men living alone (0.36). In women, we found that the higher the educational level, the greater the improvement in visual acuity (primary, 1.41; secondary, 1.76), whereas socially dependent women (0.70) were less likely to exceed the MCID. With regards to predictors related to achievement of an MCID in visual function, only dependency was associated with more improvement in men (OR: 1.39), whereas in women the educational level was the only predictor (primary: 0.72; secondary: 0.61).

CONCLUSIONS

This study found that patients with certain sociodemographic characteristics were less likely to experience an MCID in visual acuity or visual function after cataract surgery.

Influence of the MBC/MIC ratio on the antibacterial activity of vancomycin versus linezolid against methicillin-resistant Staphylococcus aureus isolates in a pharmacodynamic model simulating serum and soft tissue interstitial fluid concentrations reported in diabetic patients

OBJECTIVES

To explore serum and tissue pharmacodynamics of linezolid versus vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates with different MBC/MIC ratios.

METHODS

Five strains (vancomycin MIC/MBCs, mg/L) were used: TOL-1 (2/≥64), TOL-2 (1/16), LT-1 and LT-2 (1/8) and NT (1/2). The linezolid MIC/MBC for all strains was 2/≥64 mg/L. A two-compartment dynamic computerized device was used (inocula 10(7) cfu/mL). Free concentrations obtained in serum and interstitial fluid with twice-daily regimens of 1 g of vancomycin or 600 mg of linezolid were simulated over 48 h. ABBCs (differences between control growth curves and killing curves of bacteria exposed to antibiotics; log10 cfu × h/mL) and log10 reductions in initial inocula were calculated.

RESULTS

In serum simulations, vancomycin (AUC0-24/MIC = 251.8 for TOL-1 and 503.6 for the remaining strains) was bacteriostatic against strains with MBC/MIC ≥8, but bactericidal against NT. In interstitial fluid simulations (AUC0-24/MIC = 54.6 for TOL-1 and 109.2 for the remaining strains), initial inocula grew in all cases. Linezolid, both in serum (AUC0-24/MIC = 87.0) and in interstitial fluid (AUC0-24/MIC = 130.6) simulations, reduced initial inocula ≥2.2 log10 for all strains (apart from LT-1 in serum simulations that showed a bacteriostatic profile). ABBCs were similar in serum and interstitial fluid with linezolid, but significantly lower in interstitial fluid simulations with vancomycin.

CONCLUSIONS

From the pharmacodynamic perspective (serum concentrations), vancomycin tolerance should include MBC/MIC ≥8 since strains exhibiting this ratio showed bacteriostatic profiles similar to those obtained with isolates with MBC/MIC ratios of 16 or 32. Insufficient concentrations of vancomycin at the simulated infected site were linked to bacteriological failure. Free concentrations of linezolid at the infection site pharmacodynamically covered MRSA.

Surgical strategies for aneurysms deemed unclippable and uncoilable

Although most cerebral aneurysms can nowadays be successfully treated either by standard clipping or sole coiling, a subset of aneurysms may not be amenable to standard clipping or coiling and require alternative treatment options. Surgical options, other than clipping and/or endovascular options other than sole coiling, may be the optimal treatment plan for some complex aneurysms. Surgical strategies for such complex aneurysms include parent artery occlusion, revascularization procedures and flow redirection. In this article, we review which factors are predictive of failure of conventional aneurysm treatment options; summarize key information needed to orient treatment decision; and discuss surgical options for unclippable and uncoilable aneurysms.