Improvement In Discrimination Ability Research Articles

Auditory training remodels hippocampus-related memory in adult rats.

Consequences of perceptual training, such as improvements in discriminative ability, are highly stimulus and task specific. Therefore, most studies on auditory training-induced plasticity in adult brain have focused on the sensory aspects, particularly on functional and structural effects in the auditory cortex. Auditory training often involves, other than auditory demands, significant cognitive components. Yet, how auditory training affects cognition-related brain regions, such as the hippocampus, remains unclear. Here, we found in female rats that auditory cue-based go/no-go training significantly improved the memory-guided behaviors associated with hippocampus. The long-term potentiations of the trained rats recorded in vivo in the hippocampus were also enhanced compared with the naïve rats. In parallel, the phosphorylation level of calcium/calmodulin-dependent protein kinase II and the expression of parvalbumin-positive interneurons in the hippocampus were both upregulated. These findings demonstrate that auditory training substantially remodels the processing and function of brain regions beyond the auditory system, which are associated with task demands.

Systemic Immune-Inflammation Index Predicts Major Cardiovascular Adverse Events in Patients with ST-Segment Elevated Myocardial Infarction.

ResumoFundamento O índice de inflamação imune sistêmica (SII, systemic immune-inflammation index) tem sido descrito como um novo marcador prognóstico em tumores e doenças cardiovasculares.Objetivos Investigar a associação entre eventos cardiovasculares adversos em pacientes com infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAMCSST).Métodos Foi realizado um estudo observacional retrospectivo em 843 pacientes com IAMCSST. Os pacientes foram divididos em dois grupos segundo valores medianos de SII. A análise de regressão de Cox foi usada para detectar preditores independentes de eventos adversos cardiovasculares. A melhora na capacidade discriminatória pela adição do SII aos fatores de risco tradicionais – idade, hipertensão, diabetes mellitus, e sexo masculino para eventos adversos maiores foi calculada por estatística c, melhora da discriminação integrada (IDI), e melhora na reclassificação. Um valor de p bilateral <0,05 foi considerado estatisticamente significativo.Resultados O grupo com SII elevado apresentou idade mais avançada que o grupo com SII baixo (61,2±11,2 e 59,2±7,9, respectivamente, p=0,002). O grupo com SII elevado apresentou taxas mais altas de morte cardiovascular, infarto do miocárdio não fatal, acidente vascular cerebral não fatal, hospitalização por insuficiência cardíaca, revascularização, e eventos cardiovasculares adversos maiores que no grupo com SII baixo. O SII foi um preditor independente de todos os eventos mencionados. A adição do SII aos fatores de risco tradicionais melhorou sua capacidade discriminatória para eventos cardiovasculares. O SII foi superior à razão neutrófilo-linfócito e à razão plaqueta-linfócito para predizer eventos adversos cardiovasculares.Conclusão O SII foi um preditor independente de eventos adversos maiores em pacientes com IAMCSST e pode ser usado para melhorar a predição de eventos adversos risco, especialmente se combinado com fatores de risco tradicionais.

Superoptimal Perceptual Integration Suggests a Place-Based Representation of Pitch at High Frequencies.

Pitch, the perceptual correlate of sound repetition rate or frequency, plays an important role in speech perception, music perception, and listening in complex acoustic environments. Despite the perceptual importance of pitch, the neural mechanisms that underlie it remain poorly understood. Although cortical regions responsive to pitch have been identified, little is known about how pitch information is extracted from the inner ear itself. The two primary theories of peripheral pitch coding involve stimulus-driven spike timing, or phase locking, in the auditory nerve (time code), and the spatial distribution of responses along the length of the cochlear partition (place code). To rule out the use of timing information, we tested pitch discrimination of very high-frequency tones (>8 kHz), well beyond the putative limit of phase locking. We found that high-frequency pure-tone discrimination was poor, but when the tones were combined into a harmonic complex, a dramatic improvement in discrimination ability was observed that exceeded performance predicted by the optimal integration of peripheral information from each of the component frequencies. The results are consistent with the existence of pitch-sensitive neurons that rely only on place-based information from multiple harmonically related components. The results also provide evidence against the common assumption that poor high-frequency pure-tone pitch perception is the result of peripheral neural-coding constraints. The finding that place-based spectral coding is sufficient to elicit complex pitch at high frequencies has important implications for the design of future neural prostheses to restore hearing to deaf individuals.SIGNIFICANCE STATEMENT The question of how pitch is represented in the ear has been debated for over a century. Two competing theories involve timing information from neural spikes in the auditory nerve (time code) and the spatial distribution of neural activity along the length of the cochlear partition (place code). By using very high-frequency tones unlikely to be coded via time information, we discovered that information from the individual harmonics is combined so efficiently that performance exceeds theoretical predictions based on the optimal integration of information from each harmonic. The findings have important implications for the design of auditory prostheses because they suggest that enhanced spatial resolution alone may be sufficient to restore pitch via such implants.

Single and multiple cardiovascular biomarkers in subjects without a previous cardiovascular event.

Aims To assess the incremental value of biomarkers, including N-terminal prohormone of brain natriuretic peptide (NT-proBNP), high-sensitivity troponin T (hs-TnT), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), growth differentiation factor 15 (GDF-15), and procollagen type 1 N-terminal propeptide (P1NP), in predicting incident cardiovascular events and mortality among asymptomatic individuals from the general population, beyond traditional risk factors, including fasting glucose and renal function (cystatin C), medication use, and echocardiographic measures. Methods and results Prospective population-based cohort study of 1324 subjects without a previous cardiovascular event, who underwent baseline echocardiography and biomarker assessment between 2002 and 2006. The clinical endpoint was the composite of myocardial infarction, invasively treated stable/unstable ischemic heart disease, heart failure, stroke, or all-cause mortality. Predictive capabilities were evaluated using Cox proportional-hazards regression, Harrell's concordance index (C-index), and net reclassification improvement. Median age was 66 (interquartile range: 60-70) years, and 413 (31%) were female. During median 8.6 (interquartile range: 8.1-9.2) follow-up years, 368 (28%) composite events occurred. NT-proBNP, hs-TnT, GDF-15, and IL-6 were significantly associated with outcome, independently of traditional risk factors, medications, and echocardiography ( p < 0.05 for all). Separate addition of NT-proBNP and GDF-15 to traditional risk factors, medications, and echocardiographic measurements provided significant improvements in discriminative ability (NT-proBNP: C-index 0.714 vs. 0.703, p = 0.03; GDF-15: C-index 0.721 vs. 0.703, p = 0.02). Both biomarkers remained significant predictors of outcome upon inclusion in the same model ( p < 0.05 for both). Conclusions NT-proBNP and GDF-15 each enhance prognostication beyond traditional risk factors, glucose levels, renal function, and echocardiography in individuals without known cardiovascular disease.

Discriminative ability of commonly used indices to predict adverse outcomes after poster lumbar fusion: a comparison of demographics, ASA, the modified Charlson Comorbidity Index, and the modified Frailty Index

Background ContextAs research tools, the American Society of Anesthesiologists (ASA) physical status classification system, the modified Charlson Comorbidity Index (mCCI), and the modified Frailty Index (mFI) have been associated with complications following spine procedures. However, with respect to clinical use for various adverse outcomes, no known study has compared the predictive performance of these indices specifically following posterior lumbar fusion (PLF). PurposeThis study aimed to compare the discriminative ability of ASA, mCCI, and mFI, as well as demographic factors including age, body mass index, and gender for perioperative adverse outcomes following PLF. Study Design/SettingA retrospective review of prospectively collected data was performed. Patient SamplePatients undergoing elective PLF with or without interbody fusion were extracted from the 2011–2014 American College of Surgeons National Surgical Quality Improvement Program (NSQIP). Outcome MeasuresPerioperative adverse outcome variables assessed included the occurrence of minor adverse events, severe adverse events, infectious adverse events, any adverse event, extended length of hospital stay, and discharge to higher-level care. MethodsPatient comorbidity indices and characteristics were delineated and assessed for discriminative ability in predicting perioperative adverse outcomes using an area under the curve analysis from the receiver operating characteristics curves. ResultsIn total, 16,495 patients were identified who met the inclusion criteria. The most predictive comorbidity index was ASA and demographic factor was age. Of these two factors, age had the larger discriminative ability for three out of the six adverse outcomes and ASA was the most predictive for one out of six adverse outcomes. A combination of the most predictive demographic factor and comorbidity index resulted in improvements in discriminative ability over the individual components for five of the six outcome variables. ConclusionFor PLF, easily obtained patient ASA and age have overall similar or better discriminative abilities for perioperative adverse outcomes than numerically tabulated indices that have multiple inputs and are harder to implement in clinical practice.

Functional status and mortality prediction in community-acquired pneumonia.

Poor functional status (FS) has been suggested as a poor prognostic factor in both pneumonia and severe pneumonia in elderly patients. However, it is still unclear whether FS is associated with outcomes and improves survival prediction in community-acquired pneumonia (CAP) in the general population. Data on hospitalized patients with CAP and FS, assessed by the Eastern Cooperative Oncology Group (ECOG) scale were prospectively collected between January 2008 and December 2012. The independent association of FS with 30-day mortality in CAP patients was evaluated using multivariable logistic regression. Improvement in mortality prediction when FS was added to the CRB-65 (confusion, respiratory rate, blood pressure and age 65) score was evaluated for discrimination, reclassification and calibration. The 30-day mortality of study participants (n = 1526) was 10%. Mortality significantly increased with higher ECOG score (P for trend <0.001). In multivariable analysis, ECOG ≥3 was strongly associated with 30-day mortality (adjusted OR: 5.70; 95% CI: 3.82-8.50). Adding ECOG ≥3 significantly improved the discriminatory power of CRB-65. Reclassification indices also confirmed the improvement in discrimination ability when FS was combined with the CRB-65, with a categorized net reclassification index (NRI) of 0.561 (0.437-0.686), a continuous NRI of 0.858 (0.696-1.019) and a relative integrated discrimination improvement in the discrimination slope of 139.8 % (110.8-154.6). FS predicted 30-day mortality and improved discrimination and reclassification in consecutive CAP patients. Assessment of premorbid FS should be considered in mortality prediction in patients with CAP.

Inflammation-related genetic variants predict toxicity following definitive radiotherapy for lung cancer.

Definitive radiotherapy improves locoregional control and survival in inoperable non-small cell lung cancer (NSCLC) patients. However, radiation-induced toxicities (pneumonitis/esophagitis) are common dose-limiting inflammatory conditions. We therefore conducted a pathway-based analysis to identify inflammation-related SNPs associated with radiation-induced pneumonitis or esophagitis. 11,930 SNPs were genotyped in 201 stage I-III NSCLC patients treated with definitive radiotherapy. Validation was performed in an additional 220 NSCLC cases. After validation, 19 SNPs remained significant. A polygenic risk score (PRS) was generated to summarize the effect from validated SNPs. Significant improvements in discriminative ability were observed by adding the PRS into the clinical/epidemiological variable-based model. We then used 277 lymphoblastoid cell-lines to assess radiation sensitivity and eQTL relationships of the identified SNPs. Three genes (PRKCE,DDX58 and TNFSF7) were associated with radiation sensitivity. We concluded that inflammation-related genetic variants could contribute to the development of radiation-induced toxicities. These loci could assist in predicting those unfavorable events.

Renal function and outcomes in anticoagulated patients with non-valvular atrial fibrillation: the AMADEUS trial

Limited data are available on the impact of renal function on the outcome of patients with atrial fibrillation (AF). AMADEUS was a multicentre, randomized, open-label non-inferiority study that compared fixed-dose idraparinux with conventional anticoagulation by dose-adjusted vitamin K antagonists. We performed a post hoc analysis to assess the impact of renal function on the outcomes of anticoagulated AF patients. The primary efficacy outcome was the composite of stroke/systemic embolism (SE). The principal safety outcome of this analysis was major bleeding. We calculated c-indexes, reflecting the ability for discriminating diseased vs. non-diseased patients, and the net reclassification improvement (NRI, an index of inferior/superior performance of risk estimation scores). Of 4576 patients, 45 strokes and 103 major bleeding events occurred following an average follow-up of 325 ± 164 days. Patients with CrCl >90 mL/min had an annual stroke/SE rate of 0.6% compared with 0.8% for those with CrCl 60-90 mL/min and 2.2% for those with CrCl <60 mL/min (P < 0.001 for linear association). After adjusting for stroke risk factors, patients with CrCl <60 mL/min had more than two-fold higher risk of stroke/SE and almost 60% higher risk of major bleeding compared with those with CrCl ≥60. In patients with the CHA2DS2VASc score 1-2, CrCl <60 mL/min was associated with eight-fold higher stroke risk. When added to the CHA2DS2VASc or CHADS2 scores, CrCl <60 mL/min did not improve the c-indexes for CHADS2 (P = 0.054) or CHA2DS2VASc (P = 0.63) but resulted in significant NRI (0.26, P = 0.02) in this anticoagulated trial cohort. Renal impairment (CrCl <60 mL/min) doubles the risk of stroke and increased the risk of major bleeding by almost 60% in anticoagulated patients with AF. Renal impairment was additive to stroke risk prediction scores based on a significant NRI, but no significant improvement in discrimination ability (based on c-indexes) for CHA2DS2VASc or CHADS2 was observed.

Detection of Falsely Labeled Taro in Japan by Elemental Analysis: Improvement of Discrimination Ability Using a Sampling Plan

Detection of Falsely Labeled Taro in Japan by Elemental Analysis: Improvement of Discrimination Ability Using a Sampling Plan

Using signal detection theory to model changes in serial learning of radiological image interpretation

Signal detection theory (SDT) parameters can describe a learner's ability to discriminate (d') normal from abnormal and the learner's criterion (λ) to under or overcall abnormalities. To examine the serial changes in SDT parameters with serial exposure to radiological cases. 46 participants were recruited for this study: 20 medical students (MED), 6 residents (RES), 12 fellows (FEL), 5 staff pediatric emergency physicians (PEM), and 3 staff radiologists (RAD). Each participant was presented with 234 randomly assigned ankle radiographs using a web-based application. Participants were given a clinical scenario and considered 3 views of the ankle. They classified each case as normal or abnormal. For abnormal cases, they specified the location of the abnormality. Immediate feedback included highlighting on the images and the official radiologist's report. The low experience group (MED, RES, FEL) showed steady improvement in discrimination ability with each case, while the high experience group (PEM, RAD) had higher and stable discrimination ability throughout the exercise. There was also a difference in the way the high and low experience groups balanced sensitivity and specificity (λ) with the low experience group tending to make more errors calling positive radiographs negative. This tendency was progressively less evident with each increase in expertise level. SDT metrics provide valuable insight on changes associated with learning radiograph interpretation, and may be used to design more effective instructional strategies for a given learner group.

Discrimination of Forensic Soil Samples Using Variable-Number Tandem Repeat Typing of Bacillus cereus

Soil is one of the most important physical evidence in criminal investigations, which provides useful information regarding with the relations between suspects, victims and crime scenes. Forensic soil samples are conventionally discriminated based on physical properties, such as color and mineral examinations. It is considered that molecular analysis of DNA of soil bacteria can contribute to the criminal investigation substantially, because improvement of discrimination ability of soil will be achieved by addition of biological analysis. This report describes the application of molecular analysis, which is used for discrimination of pathogens in epidemiological investigations, to forensic soil samples. Samples were taken from three sites (A, B and C), and sites B and C, which were 300 m apart, were located about 42 km from site A. Discrimination of soil samples by color and X-ray diffraction analyses were difficult. Then, Bacillus cereus was isolated from the small amount of soil samples which were as little as the lowest quantity required by the conventional method, and discriminated by variable-number tandem repeat (VNTR). The result showed that two VNTR types isolated from A were not included among isolates from B and C even 2 years later. These results suggested that the VNTR analysis using Bacillus cereus might be useful for the discrimination of forensic soil sample analysis. However, Bacillus cereus isolate shows a diversity even isolated from the same soil, therefore further data collection is required to evaluate this method for forensic soil identification.

Macrophage infiltration of breast tumours: a prospective study.

In 50 cases of infiltrating breast cancer investigated in a prospective study the number of macrophages within each tumour was assessed. The macrophages were identified by their cytoplasmic acid phosphatase activity. The number of lymphocytes and plasma cells within the tumours were graded by a scoring technique. Significantly fewer cases with metastases were found among those with high macrophage and plasma cell scores. There was no correlation between lymphoreticular infiltration and the degree of tumour differentiation, but in cases without metastases the lymphoreticular infiltration between tumour cells was nearly always only slight when the macrophage score was low.