Publications by authors named "Ashley Cross"

Article Synopsis
  • Bacteria within human hosts face tradeoffs where mutations can be beneficial or harmful depending on the context.
  • Researchers found that a cystic fibrosis-related bacteria adapts by acquiring mutations that switch its traits, specifically changes in O-antigen expression.
  • The study indicates that whether O-antigen is beneficial or not depends on the infection site and duration, suggesting that continuous mutation during infection is more common than previously thought.
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Acute bacterial infections are often treated empirically, with the choice of antibiotic therapy updated during treatment. The effects of such rapid antibiotic switching on the evolution of antibiotic resistance in individual patients are poorly understood. Here we find that low-frequency antibiotic resistance mutations emerge, contract, and even go to extinction within days of changes in therapy.

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Background: To describe a case of pediatric sarcoidosis which initially presented as papillary conjunctivitis before manifesting as bilateral lacrimal gland swelling without other known systemic involvement.

Case Presentation: A 10-year-old female presented to the pediatric ophthalmology clinic with complaints of bilateral eyelid swelling, tearing and itching for approximately 1 month. Her history and exam were most consistent with allergic conjunctivitis, for which she was started on a standard topical regimen.

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Myeloid sarcoma (MS) is a mass-forming, extramedullary infiltration of myeloid blasts rarely presenting in cases of acute myeloid leukemia (AML). These tumoral masses rarely occur at any and multiple anatomic sites, precedent or coincident with bone marrow evidence of AML. We report a case of MS that presented as pancreatic and cardiac masses where subsequent evaluation of pleural effusion cytology rendered the diagnosis.

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isolates from chronic lung infections often overproduce alginate, giving rise to the mucoid phenotype. Isolation of mucoid strains from chronic lung infections correlates with a poor patient outcome. The most common mutation that causes the mucoid phenotype is called and results in a truncated form of the anti-sigma factor MucA that is continuously subjected to proteolysis.

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The opportunistic bacterial pathogen causes acute and chronic infections that are notoriously difficult to treat. In people with cystic fibrosis, can cause lifelong lung infections, and isolation of mucoid , resulting from the overproduction of alginate, is associated with chronic infection. The histone-like protein AlgP has previously been implicated in the control of alginate gene expression in mucoid strains, but this regulation is unclear.

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Progress in rectal cancer therapy has been hindered by the lack of effective disease-specific preclinical models that account for the unique molecular profile and biology of rectal cancer. Thus, we developed complementary patient-derived xenograft (PDX) and subsequent in vitro tumor organoid (PDTO) platforms established from preneoadjuvant therapy rectal cancer specimens to advance personalized care for rectal cancer patients. Multiple endoscopic samples were obtained from 26 Stages 2 and 3 rectal cancer patients prior to receiving 5FU/RT and implanted subcutaneously into NSG mice to generate 15 subcutaneous PDXs.

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Article Synopsis
  • Natural products, like elegaphenone, are valuable sources of antibiotics that can target various cellular functions, but pinpointing their specific targets is often complicated by bulky chemical tags.
  • Researchers used elegaphenone, which has a natural structure with a benzophenone core, to study its interactions in both Gram-positive and Gram-negative bacteria.
  • The study revealed that elegaphenone interacts with the transcription regulator AlgP and boosts the effectiveness of norfloxacin in reducing Pseudomonas aeruginosa levels within macrophages.
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is an opportunistic pathogen that causes chronic lung infections in people with cystic fibrosis (CF). Chronic isolates generally do not express O antigen and often have a mucoid phenotype, which is characterized by the overproduction of the exopolysaccharide alginate. Therefore, O antigen expression and the mucoid phenotype may be coordinately regulated upon chronic adaption to the CF lung.

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Objective: To describe salivary ductal carcinoma (SDC) presenting as an isolated lesion of the mastoid segment of the facial nerve PATIENTS:: A 70-year-old man presenting with weakness of his right lower lip that progressed to complete facial paralysis over a span of 2 weeks.

Main Outcome Measures: Clinical case records, immunohistochemical analyses, and radiological analyses including magnetic resonance imaging and positron emission tomography-computed tomography.

Results: Nodular enhancement along the mastoid segment of the facial nerve was identified without any mass within the parotid on magnetic resonance imaging or regional/distant disease on positron emission tomography-computed tomography.

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Colorectal cancer (CRC) remains the third most common malignancy and the second-leading cause of cancer-related deaths in the United States. Large multi-omic databases, such as The Cancer Genome Atlas and the International Colorectal Cancer Subtyping Consortium, have identified distinct molecular subtypes related to anatomy. The identification of genomic alterations in CRC is now critical because of the recent success and US Food and Drug Administration approval of pembrolizumab and nivolumab for microsatellite-instable tumors.

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Placental hypoxia is causally implicated in fetal growth restriction and preeclampsia, with both occurring more frequently at high altitude (>2700 m; HA). The nuclear transcription factor hypoxia-inducible factor (HIF) may facilitate placental oxygen transport at HA by increasing erythropoiesis and placental angiogenesis. We therefore investigated HIF expression and its regulatory mechanisms in placentas from normal pregnancies at high (3100 m), moderate (1600 m), and sea level (75 m) altitudes.

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