Publications by authors named "Amanda Jacobson"

Researchers have advocated elevating mouse housing temperatures from the conventional ~22 °C to the mouse thermoneutral point of 30 °C to enhance translational research. However, the impact of environmental temperature on mouse gastrointestinal physiology remains largely unexplored. Here we show that mice raised at 22 °C exhibit whole gut transit speed nearly twice as fast as those raised at 30 °C, primarily driven by a threefold increase in colon transit speed.

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Objective: To assess the accuracy of canine intraocular pressure (IOP) estimates from the eyeTelemed IOPvet indentation tonometer.

Animals Studied: Part 1 included 54 eyes from 28 Beagle dogs-23 ADAMTS10-mutants with open-angle glaucoma and 5 normals. Part 2 involved five normal canine ex vivo globes.

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Purpose: To retrospectively evaluate and describe the relationship between the use of topical corticosteroids and the development of crystalline corneal opacities (steroid keratopathy) in a colony of research Beagles and Beagle-derived dogs.

Methods: Medical records of 73 purpose-bred Beagles and Beagle-derived dogs were reviewed from June 2012 to May 2021. All dogs were treated with topical ophthalmic corticosteroids for at least 21 days.

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Article Synopsis
  • This study aimed to find out what microbes contribute to inflammatory bowel disease (IBD) by examining the bacteria present in the intestines of IBD patients.
  • Researchers identified Clostridium perfringens as a toxic bacterium prevalent in the mucosal tissues of most pediatric IBD patients, even when not detected in stool samples.
  • The presence of C. perfringens was linked to more severe symptoms in IBD, suggesting its toxins contribute to intestinal damage and pain in affected individuals, highlighting the need for regular monitoring in these patients.
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The role of ocular rigidity and biomechanics remains incompletely understood in glaucoma, including assessing an individual's sensitivity to intraocular pressure (IOP). In this regard, the clinical assessment of ocular biomechanics represents an important need. The purpose of this study was to determine a possible relationship between the G661R missense mutation in the gene and the ocular pulse amplitude (OPA), the difference between diastolic and systolic intraocular pressure (IOP), in a well-established canine model of open-angle glaucoma (OAG).

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Objective: To compare intraocular pressure (IOP) measurements in dogs taken with the Reichert® Tono-Vera® Vet rebound tonometer with and without the automatic positioning system.

Animals Studied: Measurements were taken on 49 eyes from 26 Beagle-derived dogs with variable genetics-four non-glaucomatous and 22 ADAMTS10-mutant dogs affected with different stages of open-angle glaucoma. Seventeen of the 26 dogs were measured 2-4 times on different days with variable intervals since IOP-lowering medications were administered.

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Sensory neurons of the dorsal root ganglion (DRG) are critical for maintaining tissue homeostasis by sensing and initiating responses to stimuli. While most preclinical studies of DRGs are conducted in rodents, much less is known about the mechanisms of sensory perception in primates. We generated a transcriptome atlas of mouse, guinea pig, cynomolgus monkey, and human DRGs by implementing a common laboratory workflow and multiple data-integration approaches to generate high-resolution cross-species mappings of sensory neuron subtypes.

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Neuroepithelial crosstalk is critical for gut physiology. However, the mechanisms by which sensory neurons communicate with epithelial cells to mediate gut barrier protection at homeostasis and during inflammation are not well understood. Here, we find that Nav1.

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We report long-term follow-up of the phase 1b study of venetoclax and rituximab (VenR) in patients with relapsed chronic lymphocytic leukemia (CLL), including outcomes with continuous or limited-duration therapy. Patients received venetoclax daily (200-600 mg) and rituximab over 6 months and then received venetoclax monotherapy. Patients achieving complete response (CR), CR with incomplete marrow recovery (CRi), or undetectable minimal residual disease (uMRD) assessed by flow cytometry (<10-4 cutoff) were allowed, but not required, to discontinue therapy, while remaining in the study and could be retreated with VenR upon progression.

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Venetoclax is approved as monotherapy and in combination with rituximab for relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). Two Phase 1 studies (M12-175 [NCT01328626]; M13-365 [NCT01682616]) were conducted in which patients who initially responded and then progressed on venetoclax monotherapy could receive added rituximab. Ten patients were evaluated (M12-175, n = 8; M13-365, n = 2), and five (50%) responded again upon addition of rituximab, including three complete and two partial responses.

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Combining venetoclax, a selective BCL2 inhibitor, with low-dose navitoclax, a BCL-X/BCL2 inhibitor, may allow targeting of both BCL2 and BCL-X without dose-limiting thrombocytopenia associated with navitoclax monotherapy. The safety and preliminary efficacy of venetoclax with low-dose navitoclax and chemotherapy was assessed in this phase I dose-escalation study (NCT03181126) in pediatric and adult patients with relapsed/refractory (R/R) acute lymphoblastic leukemia or lymphoblastic lymphoma. Forty-seven patients received treatment.

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The gastrointestinal tract is densely innervated by a complex network of neurons that coordinate critical physiological functions. Here, we summarize recent studies investigating the crosstalk between gut-innervating neurons, resident immune cells, and epithelial cells at homeostasis and during infection, food allergy, and inflammatory bowel disease. We introduce the neuroanatomy of the gastrointestinal tract, detailing gut-extrinsic neuron populations from the spinal cord and brain stem, and neurons of the intrinsic enteric nervous system.

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Many intracellular bacteria can establish chronic infection and persist in tissues within granulomas composed of macrophages. Granuloma macrophages exhibit heterogeneous polarization states, or phenotypes, that may be functionally distinct. Here, we elucidate a host-pathogen interaction that controls granuloma macrophage polarization and long-term pathogen persistence during Salmonella Typhimurium (STm) infection.

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Gut-innervating nociceptor sensory neurons respond to noxious stimuli by initiating protective responses including pain and inflammation; however, their role in enteric infections is unclear. Here, we find that nociceptor neurons critically mediate host defense against the bacterial pathogen Salmonella enterica serovar Typhimurium (STm). Dorsal root ganglia nociceptors protect against STm colonization, invasion, and dissemination from the gut.

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The intestinal microbiota provides colonization resistance against pathogens, limiting pathogen expansion and transmission. These microbiota-mediated mechanisms were previously identified by observing loss of colonization resistance after antibiotic treatment or dietary changes, which severely disrupt microbiota communities. We identify a microbiota-mediated mechanism of colonization resistance against Salmonella enterica serovar Typhimurium (S.

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Objective: To estimate the frequency of von Willebrand disease screening and factors that affect screening frequency in a national sample of girls and adolescents with heavy menstrual bleeding.

Methods: In this retrospective cohort study, we used a national claims database for privately and publicly insured patients between 2011 and 2013 for girls aged 10-17 years. Diagnostic criteria of heavy menstrual bleeding were the presence of one inpatient or two outpatient International Classification of Diseases, 9th Revision codes for heavy menstrual bleeding.

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Study Objective: Heavy menstrual bleeding is a common symptom reported by approximately 30% of women. The Pictorial Blood Assessment Chart (PBAC) score is often used to quantify severity of menstrual bleeding. However, the traditional PBAC paper diary might be subject to recall bias and compliance issues, especially in adolescents.

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Copper deficiency is a known cause of anemia and neutropenia that is easily remedied with copper supplementation. Copper is primarily absorbed in the stomach and proximal duodenum, so patients receiving enteral nutrition via methods that bypass this critical region may be at increased risk for copper deficiency. In pediatrics, postpyloric enteral feeding is increasingly utilized to overcome problems related to aspiration, severe reflux, poor gastric motility, and gastric outlet obstruction.

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Genome degradation correlates with host adaptation and systemic disease in Salmonella. Most lineages of the S. enterica subspecies Typhimurium cause gastroenteritis in humans; however, the recently emerged ST313 lineage II pathovar commonly causes systemic bacteremia in sub-Saharan Africa.

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Therapy-related thrombocytopenia (TRT), due to chemotherapy and/or radiation therapy, is common with pediatric cancer treatments, and it can result in dose reductions and therapy delays. Romiplostim, a thrombopoietin mimetic, is efficacious as a second-line treatment for immune thrombocytopenia in children and for TRT in adult cancer patients. However, there are no data for its use for TRT in children.

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The mammalian gastrointestinal tract is colonized by a high-density polymicrobial community where bacteria compete for niches and resources. One key competition strategy includes cell contact-dependent mechanisms of interbacterial antagonism, such as the type VI secretion system (T6SS), a multiprotein needle-like apparatus that injects effector proteins into prokaryotic and/or eukaryotic target cells. However, the contribution of T6SS antibacterial activity during pathogen invasion of the gut has not been demonstrated.

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Introduction: Numerous anatomic studies of the shoulder have quantified the size, shape, and variability of either the humerus or scapula individually. However, few have attempted to quantify the relationship of the humerus to the scapula to better understand the spatial variation of these bones in both male and female shoulders.

Methods: Seventy-four cadaveric shoulder CT scans (37 males and 37 females with statistically equivalent age and BMI) were reconstructed using Mimics ® to create 3D models of the humerus and scapula.

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The usage of and indications for total shoulder arthroplasty have grown in recent years. Certain aspects of these arthroplasty procedures can be very complex, especially in revision and fracture cases, often leading to proximal humerus bone loss. For cases with significant bone loss, there is a need for improved devices with additional options to treat a wider range of deformities while also mitigating existing complications and rates, such as poor distal fixation, inadequate soft tissue reattachment options, and joint instability.

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Over 4 million infants die each year from infections, many of which are vaccine-preventable. Young infants respond relatively poorly to many infections and vaccines, but the basis of reduced immunity in infants is ill defined. We sought to investigate whether myeloid-derived suppressor cells (MDSC) represent one potential impediment to protective immunity in early life, which may help inform strategies for effective vaccination prior to pathogen exposure.

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Host-adapted Salmonella strains are responsible for a number of disease manifestations in mammals, including an asymptomatic chronic infection in which bacteria survive within macrophages located in systemic sites. However, the host cell physiology and metabolic requirements supporting bacterial persistence are poorly understood. In a mouse model of long-term infection, we found that S.

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