Publications by authors named "Witmer A"

Understanding the biological underpinning of relapse could improve the outcomes of patients with psychosis. Relapse is elicited by multiple reasons/triggers, but the consequence frequently accompanies deteriorations of brain function, leading to poor prognosis. Structural brain imaging studies have recently been pioneered to address this question, but a lack of molecular investigations is a knowledge gap.

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Many critical issues arise when training deep neural networks using limited biological datasets. These include overfitting, exploding/vanishing gradients and other inefficiencies which are exacerbated by class imbalances and can affect the overall accuracy of a model. There is a need to develop semi-supervised models that can reduce the need for large, balanced, manually annotated datasets so that researchers can easily employ neural networks for experimental analysis.

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Cellular microscopy imaging is a common form of data acquisition for biological experimentation. Observation of gray-level morphological features allows for the inference of useful biological information such as cellular health and growth status. Cellular colonies can contain multiple cell types, making colony level classification very difficult.

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The interface of religion, spirituality, and psychiatric practice has long been of interest to the ethical psychiatrist. Some prominent early psychotherapists had a strained relationship with religion and spirituality. They posited that religion and spirituality were forms of mental illness, which discouraged the discussion of these values during treatment despite the fact that many patients subscribed to a religious or spiritual viewpoint.

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Frequently, neural network training involving biological images suffers from a lack of data, resulting in inefficient network learning. This issue stems from limitations in terms of time, resources, and difficulty in cellular experimentation and data collection. For example, when performing experimental analysis, it may be necessary for the researcher to use most of their data for testing, as opposed to model training.

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Background: Patients with poorly regulated diabetes mellitus may develop severe infectious complications. In this article we describe a diabetic patient with urosepsis, complicated by emphysematous pyelonephritis and endogenous endophthalmitis.

Case Description: A 42-year-old diabetic woman presented with drowsiness and flank pain at the right side.

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Purpose: We report a case with venous and arterial occlusive events in Sneddon syndrome and describe the accompanying fluorescein angiographic findings.

Methods: Observational case report.

Results: This 27-year-old white woman developed acute visual loss and a central scotoma in her right eye in consequence of a central retinal vein occlusion and, 2 years later, a paracentral scotoma in her left eye in consequence of an incomplete branch retinal artery occlusion.

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Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are the most prevalent causes of blindness in the Western world. The pathogenesis of neovascularization and vascular leakage, both hallmarks of these diseases, appears to have one common denominator: vascular endothelial growth factor (VEGF). Since the recent introduction of anti-VEGF therapy, intravitreal injections with these agents have become standard care in neovascular AMD, and have been found to be a valuable additional treatment strategy in several other vascular retinal diseases.

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Vascular endothelial growth factor (VEGF) has recently been implicated in several neurological disorders. Apart from its prominent role in angiogenesis, VEGF has been shown to have direct effects on neuronal and glial cells through activation of different VEGF receptor (VEGFR) types. In the present study the expression patterns of VEGFR-1, -2 and -3 were investigated in the spinal cord of control and both sporadic and familial amyotrophic lateral sclerosis (ALS) patients.

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Background/aim: Connective tissue growth factor (CTGF) stimulates extracellular matrix formation, fibrosis, and angiogenesis. It has a role in the pathogenesis of diabetic nephropathy and possibly in diabetic retinopathy (DR): in cultured retinal vascular cells CTGF is induced by VEGF-A. To further characterise this role the authors investigated CTGF expression in normal and diabetic human retina.

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Progressive tumor growth depends on angiogenesis to sustain metabolic needs of tumor cells, thus providing a potential target for cancer therapy. Malignant gliomas have retained their dismal prognosis despite aggressive multimodal conventional therapeutic approaches, illustrating the need for novel therapeutic strategies. Gliomas are a suitable tumor type for probing angiogenesis inhibition as their proliferation is characterized by a prominent proliferative vascular component.

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Background/aims: Capillary occlusion is believed to have a critical role in the development of diabetic retinopathy (DR). The exact mechanism by which it occurs, however, remains unclear. Several in vitro and animal model studies have suggested increased adhesion of leucocytes to the endothelium via upregulated ICAM-1 on the retinal microvasculature as a possible mechanism.

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VEGF-A is a major angiogenesis and permeability factor. Its cellular effects, which can be used as targets in anti-angiogenesis therapy, have mainly been studied in vitro using endothelial cell cultures. The purpose of the present study was to further characterize these effects in vivo in vascular endothelial cells and pericytes, in an experimental monkey model of VEGF-A-induced iris neovascularization.

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The treatment of otitis media with effusion is controversial and has inconsistent variations of pharmacotherapeutic practices. Current pharmacologic practices include use of antibiotics, antihistamine and/or decongestants, or a combination of antibiotics with antihistamine and/or decongestants. The effectiveness of these treatment protocols was examined through an integrative and meta-analysis of published research.

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The vascular endothelial growth factor (VEGF) family of growth factors controls pathological angiogenesis and increased vascular permeability in important eye diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). The purpose of this review is to develop new insights into the cell biology of VEGFs and vascular cells in angiogenesis and vascular leakage in general, and to provide the rationale and possible pitfalls of inhibition of VEGFs as a therapy for ocular disease. From the literature it is clear that overexpression of VEGFs and their receptors VEGFR-1, VEGFR-2 and VEGFR-3 is causing increased microvascular permeability and angiogenesis in eye conditions such as DR and AMD.

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The vascular endothelial growth factor (VEGF) family is involved in angiogenesis, and therefore VEGFs are considered as targets for anti-angiogenic therapeutic strategies against cancer. However, the physiological functions of VEGFs in quiescent tissues are unclear and may interfere with such systemic therapies. In pathological conditions, increased levels of expression of the VEGF receptors VEGFR-1, VEGFR-2, and VEGFR-3 accompany VEGF activity.

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Purpose: The vascular endothelial growth factor (VEGF) family is involved in vascular leakage and angiogenesis in diabetic retinopathy (DR) in the eye, but may also have physiological functions. Based on the hypothesis that differential VEGF receptor (VEGFR) expression in the retina is an important determinant of effects of VEGF, this study was conducted to investigate VEGFR expression in the diabetic retina and in an experimental monkey model of VEGF-A-induced retinopathy.

Methods: In retinas of 27 eyes of diabetic donors, 18 eyes of nondiabetic control donors, and 4 monkey eyes injected with PBS or VEGF-A, expression patterns of VEGFR-1, -2, and -3 in relation to leaky microvessels, as identified by the marker pathologische anatomie Leiden-endothelium (PAL-E) were studied by immunohistochemistry.

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The Louisiana Public Health Institute (LPHI) is a new governance structure that embodies cross-sector approaches to improving the public's health. Formed in 1996, LPHI's first grant was from the Robert Wood Johnson Foundation for the Turning Point initiative. The lessons learned from Turning Point have been instrumental in developing the strategic direction of LPHI and Turning Point will be sustained through ongoing projects at LPHI.

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Vascular endothelial growth factor receptor 3 (VEGFR-3, Flt-4), the receptor for vascular endothelial growth factors (VEGFs) C and D, is expressed on lymphatic endothelium and may play a role in lymphangiogenesis. In embryonic life, VEGFR-3 is essential for blood vessel development. The purpose of this study was to investigate whether VEGFR-3 is also involved in blood vessel angiogenesis in the adult.

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Purpose: The Steno hypothesis (Deckert et al. ) states that in diabetes mellitus (DM), changes in vascular heparan sulfate proteoglycan (HSPG) expression are involved in systemic endothelial dysfunction and increased capillary permeability. In diabetes-induced glomerular capillary leakage, loss of HSPG and its side chains has been documented.

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The nematode Caenorhabditis elegans with its well-described nervous system is one of the multicellular organisms of choice to study thermotaxis. The neuronal circuitry for thermosensation has been analyzed at the level of individual cells. Two methods have previously been described to study the behavior of C.

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The retinal pigment epithelium (RPE) maintains the choriocapillaris (CC) in the normal eye and is involved in the pathogenesis of choroidal neovascularization in age-related macular degeneration. Vascular endothelial growth factor-A (VEGF) is produced by differentiated human RPE cells in vitro and in vivo and may be involved in paracrine signaling between the RPE and the CC. We investigated whether there is a polarized secretion of VEGF by RPE cells in vitro.

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As the US health care system strives to function efficiently, encourage preventive and primary care, improve quality, and overcome nonfinancial barriers to care, the potential exists for community health workers to further these goals. Community health workers can increase access to care and facilitate appropriate use of health resources by providing outreach and cultural linkages between communities and delivery systems; reduce costs by providing health education, screening, detection, and basic emergency care; and improve quality by contributing to patient-provider communication, continuity of care, and consumer protection. Information sharing, program support, program evaluation, and continuing education are needed to expand the use of community health workers and better integrate them into the health care delivery system.

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