Publications by authors named "Helen Xu"

β-lactam antibiotics have been prescribed for most bacterial infections since their discovery. However, resistance to β-lactams, mediated by β-lactamase (Bla) enzymes such as extended spectrum β-lactamases (ESBLs), has become widespread. Bla inhibitors can restore the efficacy of β-lactams against resistant bacteria, an approach which preserves existing antibiotics despite declining industry investment.

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Multi-factor screenings are commonly used in diverse applications in medicine and bioengineering, including optimizing combination drug treatments and microbiome engineering. Despite the advances in high-throughput technologies, large-scale experiments typically remain prohibitively expensive. Here we introduce a machine learning platform, structure-augmented regression (SAR), that exploits the intrinsic structure of each biological system to learn a high-accuracy model with minimal data requirement.

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The ability to effectively represent microbiome dynamics is a crucial challenge in their quantitative analysis and engineering. By using autoencoder neural networks, we show that microbial growth dynamics can be compressed into low-dimensional representations and reconstructed with high fidelity. These low-dimensional embeddings are just as effective, if not better, than raw data for tasks such as identifying bacterial strains, predicting traits like antibiotic resistance, and predicting community dynamics.

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Introduction: Hepatitis delta virus (HDV) causes acute and chronic liver disease that requires the co-infection of the Hepatitis B virus and can lead to significant morbidity and mortality. Bulevirtide is a recently introduced entry inhibitor drug that acts on the sodium taurocholate cotransporting peptide, thereby preventing viral entry to target cells in chronic HDV infection. The mainstay of chronic HDV therapy prior to bulevirtide was interferon alpha, which has an undesirable side effect profile.

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Objective: After demonstration of face validity of a surgical middle ear simulator (SMS) previously, we assessed the content validity of the simulator with otolaryngology residents.

Study Design: Multicenter randomized prospective international study.

Setting: Four academic institutions.

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Neurons in the prefrontal cortex (PFC) can provide top-down regulation of sensory-affective experiences such as pain. Bottom-up modulation of sensory coding in the PFC, however, remains poorly understood. Here, we examined how oxytocin (OT) signaling from the hypothalamus regulates nociceptive coding in the PFC.

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Effective treatments for chronic pain remain limited. Conceptually, a closed-loop neural interface combining sensory signal detection with therapeutic delivery could produce timely and effective pain relief. Such systems are challenging to develop because of difficulties in accurate pain detection and ultrafast analgesic delivery.

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As pain consists of both sensory and affective components, its management by pharmaceutical agents remains difficult. Alternative forms of neuromodulation, such as electrical stimulation, have been studied in recent years as potential pain treatment options. Although electrical stimulation of the brain has shown promise, more research into stimulation frequency and targets is required to support its clinical applications.

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Purpose: To assess if a templated algorithm can improve the diagnostic performance of MRI for characterization of T2 isointense and hypointense renal masses.

Methods: In this retrospective study, 60 renal masses with histopathologic diagnoses that were also confirmed as T2 iso- or hypointense on MRI were identified (mean ± standard deviation, range: 3.9 ± 2.

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Chronic groin pain can be due to a variety of causes and is the most common complication of inguinal hernia repair surgery. The etiology of pain after inguinal hernia repair surgery is often multifactorial though injury to or scarring around the nerves in the operative region, namely the ilioinguinal nerve, genital branch of the genitofemoral nerve, and the iliohypogastric nerve, is thought to be a key factor in causing chronic post-operative hernia pain or inguinal neuralgia. Inguinal neuralgia is difficult to treat and requires a multidisciplinary approach.

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Purpose: To quantify CSF transport kinetics and brain glymphatic distribution using MRI following intrathecal injection of gadolinium contrast in healthy adults.

Subjects And Methods: Eight completely healthy volunteer subjects underwent intrathecal injection of gadolinium via image guided lumbar puncture and serial MRI's at six subsequent time points up to 11 h post-injection. Rate of enhancement and deposition were calculated for various regions and lobes of the brain.

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Objective: To evaluate the effect of the MRI-am-a-Hero program on sedation utilization for outpatient pediatric MRI studies.

Methods: The MRI-am-a-Hero program, which utilizes multimedia educational material and popular comic book characters to educate and support pediatric patients during MRI scan, was implemented at the radiology facility of a single tertiary care, academic medical center. The effect of the MRI-am-a-Hero program on sedation utilization for pediatric MRI was retrospectively evaluated using multivariate regressions yielding odds ratio of sedation before and after program implementation.

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Purpose: To automatically identify regions where prostate cancer is suspected on multi-parametric magnetic resonance images (mp-MRI).

Methods: A residual network was implemented based on segmentations from an expert radiologist on T2-weighted, apparent diffusion coefficient map, and high b-value diffusion-weighted images. Mp-MRIs from 346 patients were used in this study.

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Juvenile granulosa cell tumor (JGCT) is an extremely rare ovarian tumor that has been associated with Maffucci syndrome. It both secretes hormone and has been postulated to grow in response to hormone. We present a case of a 33-year-old G1P0 asymptomatic woman with a history of Maffucci syndrome found to have a left adnexal mass on routine ultrasonography at 13 weeks gestation.

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We present two cases of atraumatic costal cartilage fracture secondary to violent coughing. Although costal cartilage fractures due to trauma and bony rib fractures due to violent coughing have been described, to our knowledge there have been no prior reported cases of cough-induced costal cartilage fracture. It is important for radiologists to consider costal cartilage fractures, which are often more subtle than osseous injuries, in patients with chest pain, and understand that they may not always be preceded by direct trauma.

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Objective: To compare the efficacy of pain control and opioid consumption between patients who receive opioid as primary analgesic therapy and those who receive ibuprofen.

Study Design: Prospective randomized trial.

Setting: Tertiary care academic hospital.

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Selective Mutism (SM) is an anxiety disorder often diagnosed in early childhood and characterized by persistent failure to speak in certain social situations but not others. Diagnosing SM and monitoring treatment response can be quite complex, due in part to changing definitions of and scarcity of research about the disorder. Subjective self-reports and parent/teacher interviews can complicate SM diagnosis and therapy, given that similar speech problems of etiologically heterogeneous origin can be attributed to SM.

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Arbovirus transmission is modulated by host, vector, virus, and environmental factors. Even though viral fitness plays a salient role in host and vector adaptation, the transmission success of individual strains in a heterogeneous population may be stochastic. Our large-scale molecular epidemiological analyses of a dengue virus type 1 population revealed that only a subset of strains (16.

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Data sharing is increasingly recommended as a means of accelerating science by facilitating collaboration, transparency, and reproducibility. While few oppose data sharing philosophically, a range of barriers deter most researchers from implementing it in practice. To justify the significant effort required for sharing data, funding agencies, institutions, and investigators need clear evidence of benefit.

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Objective: To compare the efficacy of intratympanic gentamicin injection (ITG) on vertigo control, drop attacks, and functional level in Menière's disease patients with and without a history of migraine.

Patients: Menière's disease patients (patients with migraine and age- and sex-matched control patients without migraine) treated from 2002 to 2012 who failed medical management and received ITG, with a minimum 2-year follow up.

Intervention: ITG.

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We present a dataset combining electrophysiology and eye tracking intended as a resource for the investigation of information processing in the developing brain. The dataset includes high-density task-based and task-free EEG, eye tracking, and cognitive and behavioral data collected from 126 individuals (ages: 6-44). The task battery spans both the simple/complex and passive/active dimensions to cover a range of approaches prevalent in modern cognitive neuroscience.

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Vestibular migraine (VM) has only recently been recognized as a distinct disease entity. One reason is that its symptoms overlap greatly with those of other vestibular disorders, especially Meniere disease (MD). The pathophysiology of neither VM nor MD is entirely elucidated.

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Dengue fever is currently the most prevalent disease caused by mosquito-borne flaviviruses. Despite being potentially fatal, there are no specific antiviral therapies for Dengue virus (DENV) infections. Therefore, early, accurate, and rapid diagnosis plays an important role in proper patient management.

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