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1.
bioRxiv ; 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38895263

ABSTRACT

Parkinson's disease (PD) is characterized by the degeneration of dopaminergic neurons in the striatum, predominantly associated with motor symptoms. However, non-motor deficits, particularly sensory symptoms, often precede motor manifestations, offering a potential early diagnostic window. The impact of non-motor deficits on sensation behavior and the underlying mechanisms remains poorly understood. In this study, we examined changes in tactile sensation within a Parkinsonian state by employing a mouse model of PD induced by 6-hydroxydopamine (6-OHDA) to deplete striatal dopamine (DA). Leveraging the conserved mouse whisker system as a model for tactile-sensory stimulation, we conducted psychophysical experiments to assess sensory-driven behavioral performance during a tactile detection task in both the healthy and Parkinson-like states. Our findings reveal that DA depletion induces pronounced alterations in tactile sensation behavior, extending beyond expected motor impairments. We observed diverse behavioral deficits, spanning detection performance, task engagement, and reward accumulation, among lesioned individuals. While subjects with extreme DA depletion consistently showed severe sensory behavioral deficits, others with substantial DA depletion displayed minimal changes in sensory behavior performance. Moreover, some exhibited moderate degradation of behavioral performance, likely stemming from sensory signaling loss rather than motor impairment. The implementation of a sensory detection task is a promising approach to quantify the extent of impairments associated with DA depletion in the animal model. This facilitates the exploration of early non-motor deficits in PD, emphasizing the importance of incorporating sensory assessments in understanding the diverse spectrum of PD symptoms.

2.
Plant Physiol ; 194(4): 2217-2228, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38114089

ABSTRACT

There is growing impetus to expand the repertoire of chassis available to synthetic biologists. Chloroplast genomes present an interesting alternative for engineering photosynthetic eukaryotes; however, development of the chloroplast as a synthetic biology chassis has been limited by a lack of efficient techniques for whole-genome cloning and engineering. Here, we demonstrate two approaches for cloning the 117-kb Phaeodactylum tricornutum chloroplast genome that have 90% to 100% efficiency when screening as few as 10 yeast (Saccharomyces cerevisiae) colonies following yeast assembly. The first method reconstitutes the genome from PCR-amplified fragments, whereas the second method involves precloning these fragments into individual plasmids from which they can later be released. In both cases, overlapping fragments of the chloroplast genome and a cloning vector are homologously recombined into a singular contig through yeast assembly. The cloned chloroplast genome can be stably maintained and propagated within Escherichia coli, which provides an exciting opportunity for engineering a delivery mechanism for bringing DNA directly to the algal chloroplast. Also, one of the cloned genomes was designed to contain a single SapI site within the yeast URA3 (coding for orotidine-5'-phosphate decarboxylase) open-reading frame, which can be used to linearize the genome and integrate designer cassettes via golden-gate cloning or further iterations of yeast assembly. The methods presented here could be extrapolated to other species-particularly those with a similar chloroplast genome size and architecture (e.g. Thalassiosira pseudonana).


Subject(s)
Genome, Chloroplast , Genome, Chloroplast/genetics , Saccharomyces cerevisiae/genetics , DNA/genetics , Plasmids/genetics , Genetic Vectors/genetics , Cloning, Molecular
3.
Clin Infect Dis ; 72(Suppl 1): S27-S33, 2021 01 29.
Article in English | MEDLINE | ID: mdl-33512522

ABSTRACT

BACKGROUND: Studies have shown that healthcare-associated infections (HAIs) due to methicillin-resistant Staphylococcus aureus (MRSA) can lead to substantial healthcare costs in acute care settings. However, little is known regarding the consequences of these infections on patients in long-term care centers (LTCCs). The purpose of this study was to estimate the attributable cost of MRSA HAIs in LTCCs within the Department of Veterans Affairs (VA). METHODS: We performed a retrospective cohort study of patients admitted to VA LTCCs between 1 January 2009 and 30 September 2015. MRSA HAIs were defined as a positive clinical culture at least 48 hours after LTCC admission so as to exclude community-acquired infections. Positive cultures were further classified by site (sterile or nonsterile). We used multivariable generalized linear models and 2-part models to compare the LTCC and acute care costs between patients with and without an MRSA HAI. RESULTS: In our primary analysis, there was no difference in LTCC costs between patients with and without a MRSA HAI. There was, however, a significant increase in the odds of being transferred to an acute care facility (odds ratio, 4.40 [95% confidence interval {CI}, 3.40-5.67]) and in acute care costs ($9711 [95% CI, $6961-$12 462]). CONCLUSIONS: Our findings of high cost and increased risk of transfer from LTCC to acute care are important because they highlight the substantial clinical and economic impact of MRSA infections in this population.


Subject(s)
Cross Infection , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Cross Infection/epidemiology , Delivery of Health Care , Humans , Long-Term Care , Retrospective Studies , Staphylococcal Infections/epidemiology
5.
PLoS Pathog ; 13(12): e1006753, 2017 12.
Article in English | MEDLINE | ID: mdl-29284044

ABSTRACT

Chimeric Antigen Receptor (CAR) T-cells have emerged as a powerful immunotherapy for various forms of cancer and show promise in treating HIV-1 infection. However, significant limitations are persistence and whether peripheral T cell-based products can respond to malignant or infected cells that may reappear months or years after treatment remains unclear. Hematopoietic Stem/Progenitor Cells (HSPCs) are capable of long-term engraftment and have the potential to overcome these limitations. Here, we report the use of a protective CD4 chimeric antigen receptor (C46CD4CAR) to redirect HSPC-derived T-cells against simian/human immunodeficiency virus (SHIV) infection in pigtail macaques. CAR-containing cells persisted for more than 2 years without any measurable toxicity and were capable of multilineage engraftment. Combination antiretroviral therapy (cART) treatment followed by cART withdrawal resulted in lower viral rebound in CAR animals relative to controls, and demonstrated an immune memory-like response. We found CAR-expressing cells in multiple lymphoid tissues, decreased tissue-associated SHIV RNA levels, and substantially higher CD4/CD8 ratios in the gut as compared to controls. These results show that HSPC-derived CAR T-cells are capable of long-term engraftment and immune surveillance. This study demonstrates for the first time the safety and feasibility of HSPC-based CAR therapy in a large animal preclinical model.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , HIV Infections/immunology , HIV Infections/therapy , Hematopoietic Stem Cells/immunology , Receptors, Antigen, T-Cell/metabolism , Simian Acquired Immunodeficiency Syndrome/immunology , Simian Acquired Immunodeficiency Syndrome/therapy , Animals , CD4-Positive T-Lymphocytes/transplantation , Cell Differentiation/immunology , Cell Lineage/immunology , Disease Models, Animal , Genetic Therapy/methods , HIV Infections/virology , Hematopoietic Stem Cell Transplantation/methods , Immunotherapy/methods , Macaca nemestrina , Male , Receptors, Antigen, T-Cell/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/metabolism , Simian Acquired Immunodeficiency Syndrome/virology
6.
J Heart Valve Dis ; 26(3): 321-326, 2017 05.
Article in English | MEDLINE | ID: mdl-29092118

ABSTRACT

In patients with carcinoid syndrome, the development of carcinoid valve disease typically carries an unfavorable prognosis. We present the case of a patient with significant valvular dysfunction secondary to carcinoid valve disease. Valve replacement surgery was complicated by the development of prosthetic valve degeneration, ultimately requiring percutaneous valve implantation in a valve-in-valve fashion. The technical details of the case, as well as a review of carcinoid valve disease, including its pathophysiology, clinical manifestations, diagnostic features and management considerations, are presented.


Subject(s)
Carcinoid Heart Disease , Pulmonary Valve Insufficiency , Pulmonary Valve , Tricuspid Valve Insufficiency , Tricuspid Valve , Bioprosthesis , Carcinoid Heart Disease/complications , Carcinoid Heart Disease/diagnostic imaging , Carcinoid Heart Disease/pathology , Carcinoid Heart Disease/surgery , Cardiac Catheterization/instrumentation , Female , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation/adverse effects , Heart Valve Prosthesis Implantation/instrumentation , Humans , Middle Aged , Prosthesis Failure , Pulmonary Valve/diagnostic imaging , Pulmonary Valve/pathology , Pulmonary Valve/surgery , Pulmonary Valve Insufficiency/diagnostic imaging , Pulmonary Valve Insufficiency/etiology , Pulmonary Valve Insufficiency/pathology , Pulmonary Valve Insufficiency/surgery , Treatment Outcome , Tricuspid Valve/diagnostic imaging , Tricuspid Valve/pathology , Tricuspid Valve/surgery , Tricuspid Valve Insufficiency/diagnostic imaging , Tricuspid Valve Insufficiency/etiology , Tricuspid Valve Insufficiency/pathology , Tricuspid Valve Insufficiency/surgery
7.
J Clin Invest ; 127(1): 260-268, 2017 01 03.
Article in English | MEDLINE | ID: mdl-27941243

ABSTRACT

Chronic immune activation, immunosuppression, and T cell exhaustion are hallmarks of HIV infection, yet the mechanisms driving these processes are unclear. Chronic activation can be a driving force in immune exhaustion, and type I interferons (IFN-I) are emerging as critical components underlying ongoing activation in HIV infection. Here, we have tested the effect of blocking IFN-I signaling on T cell responses and virus replication in a murine model of chronic HIV infection. Using HIV-infected humanized mice, we demonstrated that in vivo blockade of IFN-I signaling during chronic HIV infection diminished HIV-driven immune activation, decreased T cell exhaustion marker expression, restored HIV-specific CD8 T cell function, and led to decreased viral replication. Antiretroviral therapy (ART) in combination with IFN-I blockade accelerated viral suppression, further decreased viral loads, and reduced the persistently infected HIV reservoir compared with ART treatment alone. Our data suggest that blocking IFN-I signaling in conjunction with ART treatment can restore immune function and may reduce viral reservoirs during chronic HIV infection, providing validation for IFN-I blockade as a potential therapy for HIV infection.


Subject(s)
Anti-Retroviral Agents/pharmacology , CD8-Positive T-Lymphocytes/immunology , HIV Infections/drug therapy , HIV-1/immunology , Interferon Type I/antagonists & inhibitors , Animals , CD8-Positive T-Lymphocytes/pathology , Chronic Disease , Disease Models, Animal , HIV Infections/genetics , HIV Infections/immunology , HIV Infections/pathology , Humans , Interferon Type I/genetics , Interferon Type I/immunology , Mice , Mice, Knockout
8.
J Vis Exp ; (113)2016 07 02.
Article in English | MEDLINE | ID: mdl-27404517

ABSTRACT

With the rapid development of stem cell-based gene therapies against HIV, there is pressing requirement for an animal model to study the hematopoietic differentiation and immune function of the genetically modified cells. The humanized Bone-marrow/Liver/Thymus (BLT) mouse model allows for full reconstitution of a human immune system in the periphery, which includes T cells, B cells, NK cells and monocytes. The human thymic implant also allows for thymic selection of T cells in autologous thymic tissue. In addition to the study of HIV infection, the model stands as a powerful tool to study differentiation, development and functionality of cells derived from hematopoietic stem cells (HSCs). Here we outline the construction of humanized non-obese diabetic (NOD)-severe combined immunodeficient (SCID)-common gamma chain knockout (cγ(-/-))-Bone-marrow/Liver/Thymus (NSG-BLT) mice with HSCs transduced with CD4 chimeric antigen receptor (CD4CAR) lentivirus vector. We show that the CD4CAR HSCs can successfully differentiate into multiple lineages and have anti-HIV activity. The goal of the study is to demonstrate the use of NSG-BLT mouse model as an in vivo model for engineered immunity against HIV. It is worth noting that, because lentivirus and human tissue is used, experiments and surgeries should be performed in a Class II biosafety cabinet in a Biosafety Level 2 (BSL2) with special precautions (BSL2+) facility.


Subject(s)
HIV Infections , Animals , Disease Models, Animal , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells , Humans , Mice , Mice, Inbred NOD , Mice, SCID
9.
IEEE Trans Image Process ; 22(8): 3158-67, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23743775

ABSTRACT

Visual feature extraction with scale invariant feature transform (SIFT) is widely used for object recognition. However, its real-time implementation suffers from long latency, heavy computation, and high memory storage because of its frame level computation with iterated Gaussian blur operations. Thus, this paper proposes a layer parallel SIFT (LPSIFT) with integral image, and its parallel hardware design with an on-the-fly feature extraction flow for real-time application needs. Compared with the original SIFT algorithm, the proposed approach reduces the computational amount by 90% and memory usage by 95%. The final implementation uses 580-K gate count with 90-nm CMOS technology, and offers 6000 feature points/frame for VGA images at 30 frames/s and ∼ 2000 feature points/frame for 1920 × 1080 images at 30 frames/s at the clock rate of 100 MHz.


Subject(s)
Algorithms , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Pattern Recognition, Automated/methods , Photography/methods , Subtraction Technique , Video Recording/methods , Computer Systems , Reproducibility of Results , Sensitivity and Specificity
10.
IEEE Trans Vis Comput Graph ; 13(6): 1360-7, 2007.
Article in English | MEDLINE | ID: mdl-17968085

ABSTRACT

We present a general framework for the modeling and optimization of scalable multi-projector displays. Based on this framework, we derive algorithms that can robustly optimize the visual quality of an arbitrary combination of projectors without manual adjustment. When the projectors are tiled, we show that our framework automatically produces blending maps that outperform state-of-the-art projector blending methods. When all the projectors are superimposed, the framework can produce high-resolution images beyond the Nyquist resolution limits of component projectors. When a combination of tiled and superimposed projectors are deployed, the same framework harnesses the best features of both tiled and superimposed multi-projector projection paradigms. The framework creates for the first time a new unified paradigm that is agnostic to a particular configuration of projectors yet robustly optimizes for the brightness, contrast, and resolution of that configuration. In addition, we demonstrate that our algorithms support high resolution video at real-time interactive frame rates achieved on commodity graphics platforms. This work allows for inexpensive, compelling, flexible, and robust large scale visualization systems to be built and deployed very efficiently.

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