Identification of asthma control factor in clinical notes using a hybrid deep learning model

BACKGROUND

There are significant variabilities in guideline-concordant documentation in asthma care. However, assessing clinician's documentation is not feasible using only structured data but requires labor-intensive chart review of electronic health records (EHRs). A certain guideline element in asthma control factors, such as review inhaler techniques, requires context understanding to correctly capture from EHR free text.

METHODS

The study data consist of two sets: (1) manual chart reviewed data-1039 clinical notes of 300 patients with asthma diagnosis, and (2) weakly labeled data (distant supervision)-27,363 clinical notes from 800 patients with asthma diagnosis. A context-aware language model, Bidirectional Encoder Representations from Transformers (BERT) was developed to identify inhaler techniques in EHR free text. Both original BERT and clinical BioBERT (cBERT) were applied with a cost-sensitivity to deal with imbalanced data. The distant supervision using weak labels by rules was also incorporated to augment the training set and alleviate a costly manual labeling process in the development of a deep learning algorithm. A hybrid approach using post-hoc rules was also explored to fix BERT model errors. The performance of BERT with/without distant supervision, hybrid, and rule-based models were compared in precision, recall, F-score, and accuracy.

RESULTS

The BERT models on the original data performed similar to a rule-based model in F1-score (0.837, 0.845, and 0.838 for rules, BERT, and cBERT, respectively). The BERT models with distant supervision produced higher performance (0.853 and 0.880 for BERT and cBERT, respectively) than without distant supervision and a rule-based model. The hybrid models performed best in F1-score of 0.877 and 0.904 over the distant supervision on BERT and cBERT.

CONCLUSIONS

The proposed BERT models with distant supervision demonstrated its capability to identify inhaler techniques in EHR free text, and outperformed both the rule-based model and BERT models trained on the original data. With a distant supervision approach, we may alleviate costly manual chart review to generate the large training data required in most deep learning-based models. A hybrid model was able to fix BERT model errors and further improve the performance.

Establishing an expert consensus for the operational definitions of asthma-associated infectious and inflammatory multimorbidities for computational algorithms through a modified Delphi technique

BACKGROUND

A subgroup of patients with asthma has been reported to have an increased risk for asthma-associated infectious and inflammatory multimorbidities (AIMs). To systematically investigate the association of asthma with AIMs using a large patient cohort, it is desired to leverage a broad range of electronic health record (EHR) data sources to automatically identify AIMs accurately and efficiently.

METHODS

We established an expert consensus for an operational definition for each AIM from EHR through a modified Delphi technique. A series of questions about the operational definition of 19 AIMS (11 infectious diseases and 8 inflammatory diseases) was generated by a core team of experts who considered feasibility, balance between sensitivity and specificity, and generalizability. Eight internal and 5 external expert panelists were invited to individually complete a series of online questionnaires and provide judgement and feedback throughout three sequential internal rounds and two external rounds. Panelists' responses were collected, descriptive statistics tabulated, and results reported back to the entire group. Following each round the core team of experts made iterative edits to the operational definitions until a moderate (≥ 60%) or strong (≥ 80%) level of consensus among the panel was achieved.

RESULTS

Response rates for each Delphi round were 100% in all 5 rounds with the achievement of the following consensus levels: (1) Internal panel consensus: 100% for 8 definitions, 88% for 10 definitions, and 75% for 1 definition, (2) External panel consensus: 100% for 12 definitions and 80% for 7 definitions.

CONCLUSIONS

The final operational definitions of AIMs established through a modified Delphi technique can serve as a foundation for developing computational algorithms to automatically identify AIMs from EHRs to enable large scale research studies on patient's multimorbidities associated with asthma.

Resistance to inflammation underlies enhanced fitness in clonal hematopoiesis

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Comparative Study on Overground Gait of Stroke Survivors With a Conventional Cane and a Haptic Cane

The conventional cane (single cane) is widely used to promote gait ability of stroke survivors as it provides postural stability by extending the base of support. However, its use can reduce muscle activity in the user's paretic side and cause upper limb neuropathies due to the intermittent and excessive loading of the upper limb. The provision of low magnitude support and speed regulation may result in collective improvement of gait parameters such as symmetry, balance and muscle activation. In this paper, we developed a robotic Haptic Cane (HC) that is composed of a tilted structure with motorized wheels and sensors to allow continuous haptic contact with the ground while moving at a regulated speed, and carried out gait experiments to compare the HC with an Instrumented conventional Cane (IC). The results show that use of the HC involved more continuous ground support force of a comparatively lesser magnitude than the IC, and resulted in greater improvements in the swing symmetry ratio and significant improvements in the step length symmetry ratio. Percentage of Non-Paretic Activity (%NPA) of paretic muscles (vastus medialis obliquus (VMO), semitendinosus (SMT), tibialis anterior (TBA) and gastrocnemius medialis (GCM)) in swing phase was significantly improved by the use of either device at fast speed. However, the use of HC improved %NPA of paretic VMO and SMT more than the use of IC at both preferred and fast speeds. It also significantly improved %NPA of paretic GCM in stance phase. Furthermore, comfortable speed with the HC was higher than with the IC and exhibited better RMS of anteroposterior (AP) tilt. Thus, the developed device with a simple and intuitive mechanism can provide efficient assistance for overground gait of stroke patients with a high possibility of widespread use.

Studies on Aggregated Nanoparticles Steering during Deep Brain Membrane Crossing

Many central nervous system (CNS) diseases, such as Alzheimer's disease (AD), affect the deep brain region, which hinders their effective treatment. The hippocampus, a deep brain area critical for learning and memory, is especially vulnerable to damage during early stages of AD. Magnetic drug targeting has shown high potential in delivering drugs to a targeted disease site effectively by applying a strong electromagnetic force. This study illustrates a nanotechnology-based scheme for delivering magnetic nanoparticles (MNP) to the deep brain region. First, we developed a mathematical model and a molecular dynamic simulation to analyze membrane crossing, and to study the effects of particle size, aggregation, and crossing velocities. Then, using in vitro experiments, we studied effective parameters in aggregation. We have also studied the process and environmental parameters. We have demonstrated that aggregation size can be controlled when particles are subjected to external electromagnetic fields. Our simulations and experimental studies can be used for capturing MNPs in brain, the transport of particles across the intact BBB and deep region targeting. These results are in line with previous in vivo studies and establish an effective strategy for deep brain region targeting with drug loaded MNPs through the application of an external electromagnetic field.

Acute heart failure: a mechanism underscoring sex differences in outcomes following acute coronary syndromes

Background

It remains uncertain whether female sex is itself a strong risk factor for worse outcomes in acute coronary syndromes (ACS).

Purpose

We hypothesized that sex differences in vulnerability to heart failure after ACS may modify the association between sex and outcomes.

Methods

Data were drawn from the ISACS-Archives network of registries. The study population consisted of 87,812 patients with known time from symptom onset to hospital presentation. Participants were stratified by ACS subtypes: STEMI and NSTE-ACS Data on presenting heart failure symptoms were collected from medical record abstraction. Heart failure was categorized as Killip class >2. Time from symptom onset to hospital presentation was categorized as early (≤120 minutes) or late (>120 minutes). Primary outcome measure was 30-day mortality. Estimates were performed using a parametric balancing strategy by weighting and compared by test of interaction on the log scale.

Results

Among the study sample, 30922 (35.2%) patients were women. Patient outcomes varied according to subtype of ACS. The mortality rates at 30-days were significantly higher among women vs men in STEMI (RR:1.65; 95% CI: 1.56–1.73) compared with NSTE-ACS (RR:1.18; 95% CI: 1.09–1.28; P interaction <0.0001). Similarly, the women vs men RR of heart failure was higher in STEMI (RR: 1.24; 95% CI: 1.20–1.29) compared with NSTE-ACS (RR:1.02; 95% CI: 0.97–1.08; P interaction <0.0001). Sex difference in heart failure rates with STEMI presentation were independent (P<0.0001) of early (34.3% in women vs 24.2% in men) or late (35.5% in women vs 30.7% in men) hospital presentation. The same finding was not seen in NSTE-ACS patients. Overall, women presenting with heart failure was had higher 30-day mortality than did their male counterparts with heart failure (29.8% vs 25.5%; RR: 1.24; 95% CI: 1.17–1.31).

Conclusions

Women exhibit substantially more vulnerability to heart failure in STEMI than men: a greater percentage of women have heart failure, and women with heart failure have higher 30-day mortality than men with heart failure. This finding was not seen in NSTE-ACS. heart failure on initial assessment is a key feature to explain the sex gap in mortality after ACS.

Funding Acknowledgement

Type of funding sources: None.

Statins for primary prevention among elderly men and women

Background

The debate about statins in primary prevention of cardiovascular (CV) disease is still alive, especially in old and very old adults.

Purpose

We undertook a propensity match-weighted cohort study to investigate whether statin treatment recommendations translate into improved cardiovascular (CV) outcomes in the current routine clinical care of the elderly.

Methods

We included in our analysis 5,619 people aged 65 years or older from the ISACS (International Survey of Acute Coronary Syndrome) Archives (NCT04008173) who presented to hospital with a first manifestation of CV disease. Participants were stratified as statin users versus nonusers and as old (65 to 75 years) versus very old (76 years or over) adults. We estimated the effects of statins on the most severe clinical manifestation of CV disease, namely ST segment elevation myocardial infarction (STEMI), using inverse probability of treatment weighting models. Estimates were compared by test of interaction on the log scale.

Results

The risk of STEMI was much lower in statin users than in nonusers in both patients aged 65 to 75 years (14.7% absolute risk reduction; relative risk [RR] ratio: 0.55, 95% CI 0.45 to 0.66) and those aged 76 years and older (13.3% absolute risk reduction; RR ratio: 0.58, 95% CI 0.46 to 0.72). Estimates were similar in patients with and without history of hypercholesterolemia (interaction test; p value= 0.2408). Proportional reductions in STEMI diminished with female sex in the old (p for interaction=0.002), but not in the very old age (p for interaction=0.26). We also observed a remarkable reduction in the risk of 30- day mortality from STEMI with statin therapy in both age groups (10.2% absolute risk reduction; RR ratio: 0.39; 95% CI 0.23 – 0.68 for patients aged 76 or over and 3.8% absolute risk reduction; RR ratio 0.37; 95% CI 0.17 – 0.82 for patients aged 65 to 75 years old; interaction test, p value=0.4570).

Conclusion

Preventive statin therapy in the elderly reduces the risk of STEMI with benefits in mortality from STEMI, irrespective of the presence of a history of hypercholesterolemia. This effect persists after the age of 76 years. Benefits are less pronounced in women.

Funding Acknowledgement

Type of funding sources: None.

Intraindividual Comparison between the Contrast-Enhanced Golden-Angle Radial Sparse Parallel Sequence and the Conventional Fat-Suppressed Contrast-Enhanced T1-Weighted Spin-Echo Sequence for Head and Neck MRI

BACKGROUND AND PURPOSE

The golden-angle radial sparse parallel-volumetric interpolated breath-hold (GRASP-VIBE) sequence is a recently introduced imaging technique with high resolution. This study compared the image quality between conventional fat-suppressed T1-weighted TSE and GRASP-VIBE after gadolinium enhancement in the head and neck region.

MATERIALS AND METHODS

Data from 65 patients with clinical indications for head and neck MR imaging between September 2020 and January 2021 were retrospectively reviewed. Two radiologists assessed the overall image quality, overall artifacts, and image conspicuities in the oropharynx, hypopharynx, and cervical lymph nodes according to 5-point scores (best score: 5). Interobserver agreement was assessed using weighted κ statistics. The SNR and contrast-to-noise ratio were calculated and compared between the 2 sequences using a paired Wilcoxon signed rank test.

RESULTS

The analysis included 52 patients (mean age, 60 [SD, 14 ] years; male, 71.2% [37/52]) who were mostly diagnosed with head and neck malignancies (94.3% [50/52]). κ statistics ranged from slight agreement in cervical lymph node conspicuity (κ = 0.18) to substantial agreement in oropharyngeal mucosal conspicuity (κ = 0.80) (κ range, 0.18-0.80). Moreover, GRASP-VIBE demonstrated significantly higher mean scores in overall image quality (4.68 [SD, 0.41] versus 3.66 [SD, 0.73]), artifacts (4.47 [SD, 0.48] versus 3.58 [SD, 0.71]), oropharyngeal mucosal conspicuity (4.85 [SD, 0.41] versus 4.11 [SD, 0.79]), hypopharyngeal mucosal conspicuity (4.84 [SD, 0.34] versus 3.58 [SD, 0.81]), and cervical lymph node conspicuity (4.79 [SD, 0.32] versus 4.08 [SD, 0.64]) than fat-suppressed T1-weighted TSE (all, P < .001). Furthermore, GRASP-VIBE demonstrated a higher SNR (22.8 [SD, 11.5] versus 11.3 [SD, 5.6], P < .001) and contrast-to-noise ratio (4.7 [SD, 5.4] versus 2.3 [SD, 2.7], P = .059) than fat-suppressed T1-weighted TSE.

CONCLUSIONS

GRASP-VIBE provided better image quality with fewer artifacts than conventional fat-suppressed T1-weighted TSE for the head and neck regions.

Type B valvular and supravalvular pulmonic stenosis with aberrant pre-pulmonic right coronary artery diagnosed by non-electrocardiography-gated, multislice computed tomography in a Boston terrier

Pulmonic stenosis (PS) is a common congenital heart disease in dogs. It may be associated with an aberrant coronary artery (CA) in brachycephalic breeds. If present, a CA anomaly must be identified before pulmonic valvuloplasty. A 1.7-year-old Boston terrier was referred for a grade V/VI systolic heart murmur and exercise intolerance. Echocardiography revealed combined type B valvular and supravalvular PS; an aberrant CA was also suspected. Non-electrocardiography (ECG)-gated, 160-multislice computed tomographic angiography (CTA) confirmed severe right ventricular wall hypertrophy, a hypoplastic pulmonic valve annulus, and severe supravalvular PS with a marked main pulmonary artery bulge; a single left coronary ostium with an anomalous pre-pulmonic right CA was also identified. Surgical correction with pulmonic valvuloplasty and pulmonary artery patch angioplasty under cardiopulmonary bypass was planned. The patient died intraoperatively due to profound hypotension after weaning from extracorporeal circulation. However, this is the first case report in which type B valvular and supravalvular PS with an aberrant pre-pulmonic right CA was diagnosed by non-ECG-gated, 160-multislice CTA in a Boston terrier, showing a similar level of image quality to ECG-gated CTA. Thus, in PS cases, high-slice CTA may be helpful to determine if CA anomalies are present and to establish a therapeutic plan.

Edwardsiella tarda, a rare human pathogen isolated from a perihepatic abscess: Implications of transient versus long term colonization of the gastrointestinal tract

Although gastroenteritis is the most commonly described manifestation of Edwardsiella tarda infection, the pathogenesis and transient or long-term colonization of the gastrointestinal tract of this organism in human disease is not clear. We describe a rare manifestation of E. tarda infection in a perihepatic abscess in the setting of a patient with perforated cholecystitis and its successful eradication following antibiotic treatment.

Theoretical Analysis for Using Pulsed Heating Power in Magnetic Hyperthermia Therapy of Breast Cancer

In magnetic hyperthermia, magnetic nanoparticles (MNPs) are used to generate heat in an alternating magnetic field to destroy cancerous cells. This field can be continuous or pulsed. Although a large amount of research has been devoted to studying the efficiency and side effects of continuous fields, little attention has been paid to the use of pulsed fields. In this simulation study, Fourier's law and COMSOL software have been utilized to identify the heating power necessary for treating breast cancer under blood flow and metabolism to obtain the optimized condition among the pulsed powers for thermal ablation. The results showed that for small source diameters (not larger than 4 mm), pulsed powers with high duties were more effective than continuous power. Although by increasing the source domain the fraction of damage caused by continuous power reached the damage caused by the pulsed powers, it affected the healthy tissues more (at least two times greater) than the pulsed powers. Pulsed powers with high duty (0.8 and 0.9) showed the optimized condition and the results have been explained based on the Arrhenius equation. Utilizing the pulsed powers for breast cancer treatment can potentially be an efficient approach for treating breast tumors due to requiring lower heating power and minimizing side effects to the healthy tissues.

The Heating Efficiency and Imaging Performance of Magnesium Iron Oxide@tetramethyl Ammonium Hydroxide Nanoparticles for Biomedical Applications

Multifunctional magnetic nanomaterials displaying high specific loss power (SLP) and high imaging sensitivity with good spatial resolution are highly desired in image-guided cancer therapy. Currently, commercial nanoparticles do not sufficiently provide such multifunctionality. For example, Resovist® has good image resolution but with a low SLP, whereas BNF® has a high SLP value with very low image resolution. In this study, hydrophilic magnesium iron oxide@tetramethyl ammonium hydroxide nanoparticles were prepared in two steps. First, hydrophobic magnesium iron oxide nanoparticles were fabricated using a thermal decomposition technique, followed by coating with tetramethyl ammonium hydroxide. The synthesized nanoparticles were characterized using XRD, DLS, TEM, zeta potential, UV-Vis spectroscopy, and VSM. The hyperthermia and imaging properties of the prepared nanoparticles were investigated and compared to the commercial nanoparticles. One-dimensional magnetic particle imaging indicated the good imaging resolution of our nanoparticles. Under the application of a magnetic field of frequency 614.4 kHz and strength 9.5 kA/m, nanoparticles generated heat with an SLP of 216.18 W/g, which is much higher than that of BNF (14 W/g). Thus, the prepared nanoparticles show promise as a novel dual-functional magnetic nanomaterial, enabling both high performance for hyperthermia and imaging functionality for diagnostic and therapeutic processes.

Novel double beta-lactam therapy for Granulicatella adiacens infective endocarditis

Granulicatella adiacens, a nutritionally variant streptococci (NVS) is a well described organism associated with endocarditis. Previously communicated cases have documented the use of double beta-lactam therapy with ampicillin and ceftriaxone to treat patients with infective endocarditis due to Enterococcus faecalis and Streptocossus pneumoniae. We describe the first case of Granulicatella adiacens infective endocarditis in a patient successfully treated with the combination of intravenous ampicillin and ceftriaxone and document their synergistic activity.

Deep Learning Identification of Asthma Inhaler Techniques in Clinical Notes

There are significant variabilities in clinicians' guideline-concordant documentation in asthma care. However, assessing clinicians' documentation is not feasible using only structured data but requires labor intensive chart review of electronic health records. Although the national asthma guidelines are available it is still challenging to use them as a real-time tool for providing feedback on adhering documentation guidelines for asthma care improvement. A certain guideline element, such as teaching or reviewing inhaler techniques, is difficult to capture by handcrafted rules since it requires contextual understanding of clinical narratives. This study examined a deep learning based natural language model, Bidirectional Encoder Representations from Transformers (BERT) coupled with distant supervision to identify inhaler techniques from clinical narratives. The BERT model with distant supervision outperformed the rule-based approach and achieved performance gain compared with the BERT without distant supervision.

A novel xeno-organoid approach: exploring the crosstalk between human iPSC-derived PGC-like and rat testicular cells

Specification of germ cell-like cells from induced pluripotent stem cells has become a clinically relevant tool for research. Research on initial embryonic processes is often limited by the access to foetal tissue, and in humans, the molecular events resulting in primordial germ cell (PGC) specification and sex determination remain to be elucidated. A deeper understanding of the underlying processes is crucial to describe pathomechanisms leading to impaired reproductive function. Several protocols have been established for the specification of human pluripotent stem cell towards early PGC-like cells (PGCLC), currently representing the best model to mimic early human germline developmental processes in vitro. Further sex determination towards the male lineage depends on somatic gonadal cells providing the necessary molecular cues. By establishing a culture system characterized by the re-organization of somatic cells from postnatal rat testes into cord-like structures and optimizing efficient PGCLC specification protocols, we facilitated the co-culture of human germ cell-like cells within a surrogate testicular microenvironment. Specified conditions allowed the survival of rat somatic testicular and human PGCLCs for 14 days. Human cells maintained the characteristic expression of octamer-binding transcription factor 4, SRY-box transcription factor 17, and transcription factor AP-2 gamma and were recovered from the xeno-organoids by cell sorting. This novel xeno-organoid approach will allow the in vitro exploration of early sex determination of human PGCLCs.

Anterior skull base olfactory tumours, which is what? A case report and review

Intracranial schwannomas not originating from cranial nerves are rare. In this paper, we report a case of a 50-year-old male who presented with worsening headaches, diplopia and nausea over two years. Radiological imaging revealed a large tumour arising from the olfactory groove region with a preoperative diagnosis of olfactory groove meningioma (OGM). Intraoperatively, the tumour originated from the region of the attachment of the falx to the crista galli. The patient recovered without complication and histopathology reported an unexpected diagnosis of WHO Grade 1 schwannoma. However, as olfactory groove schwannomas (OGSs) cannot be distinguished from olfactory ensheathing cell tumours (OECTs), it is possible that the tumour could have been either an OGS or an OECT. Distinguishing between OGSs, OECTs and OGMs preoperatively is difficult. OGMs exhibit distinct histopathological features from OGSs/OECTs, however, OGSs and OECTs currently cannot be distinguished from each other. Here, we review the literature to discuss the differentiating features and cellular origins of these three tumours.