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1.
Mol Ther ; 26(5): 1354-1365, 2018 05 02.
Article in English | MEDLINE | ID: mdl-29606504

ABSTRACT

Glioblastoma (GBM) is the least treatable type of brain tumor, afflicting over 15,000 people per year in the United States. Patients have a median survival of 16 months, and over 95% die within 5 years. The chemokine receptor ACKR3 is selectively expressed on both GBM cells and tumor-associated blood vessels. High tumor expression of ACKR3 correlates with poor prognosis and potential treatment resistance, making it an attractive therapeutic target. We engineered a single chain FV-human FC-immunoglobulin G1 (IgG1) antibody, X7Ab, to target ACKR3 in human and mouse GBM cells. We used hydrodynamic gene transfer to overexpress the antibody, with efficacy in vivo. X7Ab kills GBM tumor cells and ACKR3-expressing vascular endothelial cells by engaging the cytotoxic activity of natural killer (NK) cells and complement and the phagocytic activity of macrophages. Combining X7Ab with TMZ allows the TMZ dosage to be lowered, without compromising therapeutic efficacy. Mice treated with X7Ab and in combination with TMZ showed significant tumor reduction by MRI and longer survival overall. Brain-tumor-infiltrating leukocyte analysis revealed that X7Ab enhances the activation of M1 macrophages to support anti-tumor immune response in vivo. Targeting ACKR3 with immunotherapeutic monoclonal antibodies (mAbs) in combination with standard of care therapies may prove effective in treating GBM.


Subject(s)
Antibodies, Monoclonal/pharmacology , Glioblastoma/immunology , Glioblastoma/metabolism , Receptors, CXCR/antagonists & inhibitors , Temozolomide/pharmacology , Animals , Antibodies, Monoclonal/metabolism , Antibody Affinity/immunology , Antineoplastic Agents, Immunological/pharmacology , Cell Line, Tumor , Cytotoxicity, Immunologic/drug effects , Disease Models, Animal , Drug Synergism , Glioblastoma/diagnosis , Glioblastoma/mortality , Humans , Magnetic Resonance Imaging , Mice , Mortality , Protein Binding/immunology , Receptors, CXCR/metabolism , Xenograft Model Antitumor Assays
2.
PLoS Negl Trop Dis ; 10(2): e0004396, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26863440

ABSTRACT

BACKGROUND: The transitional period between the oncosphere and the cysticercus of Taenia solium is the postoncospheral (PO) form, which has not yet been completely characterized. The aim of this work was to standardize a method to obtain T. solium PO forms by in vitro cultivation. We studied the morphology of the PO form and compared the expression of antigenic proteins among the PO form, oncosphere, and cysticerci stages. METHODOLOGY/PRINCIPAL FINDINGS: T. solium activated oncospheres were co-cultured with ten cell lines to obtain PO forms, which we studied at three stages of development--days 15, 30, and 60. A high percentage (32%) of PO forms was obtained using HCT-8 cells in comparison to the other cell lines. The morphology was observed by bright field, scanning, and transmission electron microscopy. Morphology of the PO form changed over time, with the six hooks commonly seen in the oncosphere stage disappearing in the PO forms, and vesicles and microtriches observed in the tegument. The PO forms grew as they aged, reaching a diameter of 2.5 mm at 60 days of culture. 15-30 day PO forms developed into mature cysticerci when inoculated into rats. Antigenic proteins expressed in the PO forms are also expressed by the oncosphere and cysticerci stages, with more cysticerci antigenic proteins expressed as the PO forms ages. CONCLUSIONS/SIGNIFICANCE: This is the first report of an in vitro production method of T. solium PO forms. The changes observed in protein expression may be useful in identifying new targets for vaccine development. In vitro culture of PO form will aid in understanding the host-parasite relationship, since the structural changes of the developing PO forms may reflect the parasite's immunoprotective mechanisms. A wider application of this method could significantly reduce the use of animals, and thus the costs and time required for further experimental investigations.


Subject(s)
Antigens, Helminth/analysis , Taenia solium/anatomy & histology , Taenia solium/growth & development , Animals , Blotting, Western , Cell Line , Coculture Techniques , Gene Expression Profiling , Humans , Microscopy , Taenia solium/genetics
3.
Gut ; 64(10): 1569-77, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25387891

ABSTRACT

BACKGROUND: Diminutive (≤ 5 mm) colorectal polyps are common, and overwhelmingly benign. Routinely, after polypectomy, they are examined pathologically to determine the surveillance intervals. Advances in equipment and techniques, such as narrow-band imaging (NBI) colonoscopy, now permit reliable real-time optical diagnosis. METHODS: We conducted a randomised single-masked study involving three institutions to determine whether optical diagnosis of diminutive colorectal polyps meets clinical practice standards and reduces the need for histopathology. We randomly assigned eligible patients undergoing routine high-definition colonoscopy to optical diagnosis using near focus versus standard view, using computer-generated block sequence. By validated criteria, we rendered an optical diagnosis and a confidence level (high vs low) for all polyps, using NBI. Our primary endpoint was the number of accurate high-confidence optical diagnoses compared with central blinded pathology in the two groups. We analysed data using intention to treat. FINDINGS: We enrolled 558 subjects, and randomly assigned 281 to near focus and 277 to standard view optical diagnosis. We detected 1309 predominantly diminutive (74.5%) and neoplastic (60.0%) polyps. Endoscopists were significantly more likely, OR 2.2 (95% CI 1.6 to 3.0, p<0.0001), to make a high-confidence optical diagnosis with near focus (85.1%) than standard (72.6%) view. High-confidence diagnoses had 96.4% and 92.0% negative predictive value, respectively. Of all polyps, 75.3% (95% CI71.3% to 78.9%) had a high-confidence accurate prediction using near focus, compared with 63.1% (95% CI 58.5% to 67.6%) using standard view. Optical versus histopathological diagnosis showed excellent agreement between the surveillance intervals, 93.5% in near focus and 92.2% in standard view. The median diagnosis time was 14 s. CONCLUSIONS: Real-time optical diagnosis using NBI colonoscopy may replace the pathology diagnosis for the majority of diminutive colorectal polyps. Using colonoscopy with near focus view increases the confidence level of the optical diagnosis. Optical diagnosis would be a paradigm shift in clinical practice of colonoscopy for colorectal cancer screening. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT01288833.


Subject(s)
Colonic Polyps/diagnosis , Colonoscopy/methods , Colorectal Neoplasms/diagnosis , Narrow Band Imaging/methods , Diagnosis, Differential , Follow-Up Studies , Humans , Predictive Value of Tests , Retrospective Studies , Single-Blind Method
4.
Am J Dermatopathol ; 36(10): 853-5, 2014 Oct.
Article in English | MEDLINE | ID: mdl-23503318

ABSTRACT

Chromhidrosis is a rare idiopathic disorder characterized by colored secretions most typically from the malar cheeks, axilla, or areolar regions. Histologically, chromhidrosis is notable for glandular structures with decapitation secretion indicating ectopic apocrine glands in the dermis, and the presence of lipofuscin pigments under ultraviolet fluorescence and in cytology smears. This case report describes a 26-year-old man who presented with a 2- to 3-year history of black-colored secretions on the bilateral malar cheeks, present on exertion or with squeezing of the cheeks. A 3-mm punch biopsy of the left cheek demonstrated histopathologic findings characteristic of chromhidrosis under hematoxylin and eosin staining and ultraviolet fluorescence. To our best knowledge, this is the second case report in the literature of an adult male being affected by chromhidrosis, and the first of an adult male with black-colored malar cheek secretions in chromhidrosis.


Subject(s)
Pigmentation Disorders/pathology , Sweat Gland Diseases/pathology , Adult , Apocrine Glands/pathology , Cheek/pathology , Humans , Lipofuscin/metabolism , Male
5.
J Clin Invest ; 121(6): 2336-49, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21606594

ABSTRACT

Chronic rejection, manifested as small airway fibrosis (obliterative bronchiolitis [OB]), is the main obstacle to long-term survival in lung transplantation. Recent studies demonstrate that the airways involved in a lung transplant are relatively hypoxic at baseline and that OB pathogenesis may be linked to ischemia induced by a transient loss of airway microvasculature. Here, we show that HIF-1α mediates airway microvascular repair in a model of orthotopic tracheal transplantation. Grafts with a conditional knockout of Hif1a demonstrated diminished recruitment of recipient-derived Tie2⁺ angiogenic cells to the allograft, impaired repair of damaged microvasculature, accelerated loss of microvascular perfusion, and hastened denudation of epithelial cells. In contrast, graft HIF-1α overexpression induced via an adenoviral vector prolonged airway microvascular perfusion, preserved epithelial integrity, extended the time window for the graft to be rescued from chronic rejection, and attenuated airway fibrotic remodeling. HIF-1α overexpression induced the expression of proangiogenic factors such as Sdf1, Plgf, and Vegf, and promoted the recruitment of vasoreparative Tie2⁺ cells. This study demonstrates that a therapy that enhances vascular integrity during acute rejection may promote graft health and prevent chronic rejection.


Subject(s)
Bronchiolitis Obliterans/physiopathology , Genetic Therapy , Genetic Vectors/therapeutic use , Graft Rejection/prevention & control , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Ischemia/etiology , Trachea/transplantation , Adenoviridae/genetics , Angiogenic Proteins/biosynthesis , Angiogenic Proteins/genetics , Animals , Bronchiolitis Obliterans/immunology , Cell Hypoxia , Cell Survival , Chemokine CXCL12/physiology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Endothelial Cells/transplantation , Graft Rejection/immunology , Graft Rejection/physiopathology , Hypoxia-Inducible Factor 1, alpha Subunit/deficiency , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Ischemia/physiopathology , Ischemia/prevention & control , Mice , Mice, Inbred Strains , Mice, Knockout , Microcirculation , Neovascularization, Pathologic/physiopathology , Receptor Protein-Tyrosine Kinases/physiology , Receptor, TIE-2 , Receptors, CXCR4/antagonists & inhibitors , Receptors, CXCR4/physiology , Recombinant Fusion Proteins/physiology , Trachea/blood supply , Trachea/immunology , Trachea/pathology
6.
Rare Tumors ; 3(4): e43, 2011 Oct 21.
Article in English | MEDLINE | ID: mdl-22355498

ABSTRACT

A 57-year-old with a 9-year history of increased abdominal girth, presented with increased abdominal pain, anemia, and acute renal failure. His past medical history was only remarkable for a previous lung cancer 21 years ago that was treated with a right upper lung lobectomy. A computed tomography (CT) scan of the patient's abdomen showed a solitary 20×20×25cm cystic splenic mass. The patient underwent an urgent splenectomy. Intra-operatively a large splenic cystic cavity was found with a solid inferior splenic mass. An exhaustive histological analysis of the splenic mass confirmed a clear cell carcinoma with low malignant potential that likely represented a metastatic lesion from the patient's previous distant lung cancer. Postoperatively the patient recovered well and at 1-year followup the patient demonstrated no further evidence of metastatic disease. This case is extremely unique and provides a very rare example of a metastatic solitary clear cell carcinoma to the spleen, with a presumed latency period of more than 20 years.

7.
Case Rep Crit Care ; 2011: 562516, 2011.
Article in English | MEDLINE | ID: mdl-24826323

ABSTRACT

Acute necrotizing encephalopathy (ANE) is a severe neurological complication of influenza infection, including H1N1 influenza. Many cases of ANE have been reported in the pediatric literature, but very few cases have been described in adults. The cause of ANE remains unknown-the influenza virus is not known to be neurotropic, and evidence of direct viral involvement of the central nervous system (CNS) has not been demonstrated in the limited cases of ANE in which pathological specimens have been obtained. Here we report a fatal case of ANE from H1N1 influenza infection in an adult. Neuroimaging and postmortem analysis both showed widespread brain edema, necrosis, and hemorrhage, but molecular studies and postmortem pathology revealed no evidence of direct viral involvement of the CNS. This case of fatal ANE in an adult is consistent with the hypothesis generated from pediatric cases that the host immune response, and not direct viral invasion of the CNS, is responsible for pathogenesis of ANE.

8.
Infect Immun ; 75(11): 5158-66, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17698575

ABSTRACT

The specific mechanisms underlying Taenia solium oncosphere adherence and penetration in the host have not been studied previously. We developed an in vitro adhesion model assay to evaluate the mechanisms of T. solium oncosphere adherence to the host cells. The following substrates were used: porcine intestinal mucosal scrapings (PIMS), porcine small intestinal mucosal explants (PSIME), Chinese hamster ovary cells (CHO cells), epithelial cells from ileocecal colorectal adenocarcinoma (HCT-8 cells), and epithelial cells from colorectal adenocarcinoma (Caco-2 cells). CHO cells were used to compare oncosphere adherence to fixed and viable cells, to determine the optimum time of oncosphere incubation, to determine the role of sera and monolayer cell maturation, and to determine the effect of temperature on oncosphere adherence. Light microscopy, scanning microscopy, and transmission microscopy were used to observe morphological characteristics of adhered oncospheres. This study showed in vitro adherence of activated T. solium oncospheres to PIMS, PSIME, monolayer CHO cells, Caco-2 cells, and HCT-8 cells. The reproducibility of T. solium oncosphere adherence was most easily measured with CHO cells. Adherence was enhanced by serum-binding medium with >5% fetal bovine serum, which resulted in a significantly greater number of oncospheres adhering than the number adhering when serum at a concentration less than 2.5% was used (P < 0.05). Oncosphere adherence decreased with incubation of cells at 4 degrees C compared with the adherence at 37 degrees C. Our studies also demonstrated that T. solium oncospheres attach to cells with elongated microvillus processes and that the oncospheres expel external secretory vesicles that have the same oncosphere processes.


Subject(s)
Cell Adhesion/physiology , Epithelial Cells/parasitology , Mucous Membrane/parasitology , Taenia solium/physiology , Animals , CHO Cells , Caco-2 Cells , Cricetinae , Cricetulus , Humans , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Reproducibility of Results , Serum , Swine , Temperature
9.
Neuron ; 53(2): 201-15, 2007 Jan 18.
Article in English | MEDLINE | ID: mdl-17224403

ABSTRACT

Targeting of synaptic molecules to their proper location is essential for synaptic differentiation and plasticity. PSD-95/Dlg proteins have been established as key components of the postsynapse. However, the molecular mechanisms regulating the synaptic targeting, assembly, and disassembly of PSD-95/Dlg are not well understood. Here we show that PAR-1 kinase, a conserved cell polarity regulator, is critically involved in controlling the postsynaptic localization of Dlg. PAR-1 is prominently localized at the Drosophila neuromuscular junction (NMJ). Loss of PAR-1 function leads to increased synapse formation and synaptic transmission, whereas overexpression of PAR-1 has the opposite effects. PAR-1 directly phosphorylates Dlg at a conserved site and negatively regulates its mobility and targeting to the postsynapse. The ability of a nonphosphorylatable Dlg to largely rescue PAR-1-induced synaptic defects supports the idea that Dlg is a major synaptic substrate of PAR-1. Control of Dlg synaptic targeting by PAR-1-mediated phosphorylation thus constitutes a critical event in synaptogenesis.


Subject(s)
Drosophila Proteins/metabolism , Drosophila Proteins/physiology , Drosophila/physiology , Neuromuscular Junction/physiology , Protein Kinases/physiology , Synapses/physiology , Tumor Suppressor Proteins/metabolism , Animals , Animals, Genetically Modified , Fluorescence Recovery After Photobleaching , Glycogen Synthase Kinase 3 , In Vitro Techniques , Neuromuscular Junction/metabolism , Neuromuscular Junction/ultrastructure , Phosphorylation , Protein Kinases/metabolism , Protein Serine-Threonine Kinases , Synapses/ultrastructure , Synaptic Transmission/physiology , Tissue Distribution
10.
FEBS Lett ; 580(9): 2351--2357, 2006 Apr 17.
Article in English | MEDLINE | ID: mdl-16616523

ABSTRACT

Mallory bodies (MBs) are characteristic of several liver disorders, and consist primarily of keratins with transglutaminase-generated keratin crosslinks. We tested the effect of the transglutaminase-2 (TG2) inhibitor KCC009 on MB formation in a mouse model fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). KCC009 decreased DDC-induced liver enlargement without affecting MB formation or extent of liver injury. TG2 protein and activity increased after DDC feeding and localized within and outside hepatocytes. KCC009 inhibited DDC-induced hepatomegaly by affecting hepatocyte cell size rather than proliferation. Hence, TG2 is a potential mediator of injury-induced hepatomegaly via modulation of hepatocyte hypertrophy, and KCC009-mediated TG2 inhibition does not affect mouse MB formation.


Subject(s)
Enzyme Inhibitors/administration & dosage , GTP-Binding Proteins/antagonists & inhibitors , Inclusion Bodies/drug effects , Isoxazoles/administration & dosage , Liver Diseases/drug therapy , Proteins/metabolism , Transglutaminases/antagonists & inhibitors , Animals , Cell Size/drug effects , Chemical and Drug Induced Liver Injury , Dicarbethoxydihydrocollidine/administration & dosage , Dicarbethoxydihydrocollidine/toxicity , GTP-Binding Proteins/metabolism , Hepatomegaly/chemically induced , Hepatomegaly/drug therapy , Hepatomegaly/enzymology , Hepatomegaly/pathology , Humans , Inclusion Bodies/metabolism , Inclusion Bodies/pathology , Keratins/metabolism , Liver Diseases/enzymology , Liver Diseases/pathology , Mice , Mice, Inbred C3H , Protein Glutamine gamma Glutamyltransferase 2 , Transglutaminases/metabolism
11.
Ann Thorac Surg ; 80(5): 1909-11, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16242482

ABSTRACT

A 43-year-old woman underwent mitral valve replacement for severe mitral regurgitation nine years after orthotopic heart transplant. Histopathology showed chronic rejection of the mitral valve with lymphocytic infiltrates. The patient is well at one year follow-up. This report describes an identified case of chronic mitral valve rejection requiring valve replacement.


Subject(s)
Heart Valve Prosthesis Implantation , Mitral Valve Insufficiency/surgery , Adult , Female , Graft Rejection , Heart Transplantation , Humans , Mitral Valve Insufficiency/etiology , Mitral Valve Insufficiency/pathology , Postoperative Complications
12.
Proc Natl Acad Sci U S A ; 102(38): 13670-5, 2005 Sep 20.
Article in English | MEDLINE | ID: mdl-16155123

ABSTRACT

Parkinson's disease (PD) is the most common movement disorder characterized by dopaminergic dysfunction and degeneration. The cause of most PD cases is unknown, although postmortem studies have implicated the involvement of oxidative stress. The identification of familial PD-associated genes offers the opportunity to study mechanisms of PD pathogenesis in model organisms. Here, we show that DJ-1A, a Drosophila homologue of the familial PD-associated gene DJ-1, plays an essential role in oxidative stress response and neuronal maintenance. Inhibition of DJ-1A function through RNA interference (RNAi) results in cellular accumulation of reactive oxygen species, organismal hypersensitivity to oxidative stress, and dysfunction and degeneration of dopaminergic and photoreceptor neurons. To identify other genes that may interact with DJ-1A in regulating cell survival, we performed genetic interaction studies and identified components of the phosphatidylinositol 3-kinase (PI3K)/Akt-signaling pathway as specific modulators of DJ-1A RNAi-induced neurodegeneration. PI3K signaling suppresses DJ-1A RNAi phenotypes at least in part by reducing cellular reactive oxygen species levels. Consistent with the genetic interaction results, we also found reduced phosphorylation of Akt in DJ-1A RNAi animals, indicating an impairment of PI3K/Akt signaling by DJ-1A down-regulation. Together with recent findings in mammalian systems, these results implicate impairments of PI3K/Akt signaling and oxidative stress response in DJ-1-associated disease pathogenesis. We also observed impairment of PI3K/Akt signaling in the fly parkin model of PD, hinting at a common molecular event in the pathogenesis of PD. Manipulation of PI3K/Akt signaling may therefore offer therapeutic benefits for the treatment of PD.


Subject(s)
Drosophila Proteins/metabolism , Oxidative Stress/physiology , Phosphatidylinositol 3-Kinases/metabolism , Photoreceptor Cells, Invertebrate/metabolism , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Signal Transduction/physiology , Animals , Disease Models, Animal , Dopamine/metabolism , Drosophila , Drosophila Proteins/genetics , Enzyme Activation/genetics , Humans , Oxidative Stress/genetics , Parkinson Disease/genetics , Parkinson Disease/metabolism , Parkinson Disease/pathology , Proto-Oncogene Proteins c-akt , RNA Interference/physiology , RNA, Small Interfering/genetics , Reactive Oxygen Species/metabolism , Signal Transduction/genetics
13.
Crit Care Med ; 32(4): 1041-8, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15071399

ABSTRACT

OBJECTIVE: The sympathetic nervous system enhances cardiac muscle function by activating beta adrenergic receptors (betaARs). Recent studies suggest that chronic betaAR stimulation is detrimental, however, and that it may play a role in the clinical deterioration of patients with congestive heart failure. To examine the impact of chronic beta1AR and beta2AR subtype stimulation individually, we studied the cardiovascular effects of catecholamine infusions in betaAR subtype knockout mice (beta1KO, beta2KO). DESIGN: Prospective, randomized, experimental study. SETTING: Animal research laboratory. SUBJECTS: beta1KO and beta2KO mice and wild-type controls. INTERVENTIONS: The animals were subjected to 2 wks of continuous infusion of the betaAR agonist isoproterenol. Analyses of cardiac function and structure were performed during and 3 days after completion of the infusions. Functional studies included graded exercise treadmill testing, in vivo assessments of left ventricular function using Mikro-Tip catheter transducers, right ventricular pressure measurements, and analyses of organ weight to body weight ratios. Structural studies included heart weight measurements, assessments of myocyte ultrastructure using electron microscopy, and in situ terminal deoxynucleotidyl transferase-mediated biotin-dUTP nick-end labeling staining to quantitate myocyte apoptosis. MEASUREMENTS AND MAIN RESULTS: We found that isoproterenol-treated beta2KO mice experienced greater mortality rates (p =.001, chi-square test using Fisher's exact method) and increased myocyte apoptosis at 3- and 7-day time points (p =.04 and p =.0007, respectively, two-way analysis of variance). CONCLUSION: The results of this study suggest that in vivo beta2AR activation is antiapoptotic and contributes to myocardial protection.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Apoptosis/drug effects , Isoproterenol/pharmacology , Myocardial Contraction/drug effects , Myocardium/pathology , Receptors, Adrenergic, beta-2/drug effects , Ventricular Function, Left/drug effects , Ventricular Function, Right/drug effects , Animals , Exercise Test/drug effects , Heart/innervation , Infusions, Intravenous , Male , Mice , Mice, Knockout , Microscopy, Electron , Receptors, Adrenergic, beta-1/drug effects , Receptors, Adrenergic, beta-1/genetics , Receptors, Adrenergic, beta-2/genetics , Survival Rate , Sympathetic Nervous System/drug effects
14.
J Infect Dis ; 188(6): 801-8, 2003 Sep 15.
Article in English | MEDLINE | ID: mdl-12964110

ABSTRACT

Whipple disease (WD) is a systemic disorder caused by the bacterium Tropheryma whipplei. Since the recognition of a bacterial etiology in 1961, many attempts have been made to cultivate this bacterium in vitro. It was eventually isolated, in 2000, from an infected heart valve, in coculture with human fibroblasts. Here we report the isolation of 2 new strains of T. whipplei from cerebrospinal fluid (CSF) of 2 patients with intestinal WD but no neurological signs or symptoms. One culture-positive specimen was obtained before treatment; the other was obtained 12 months after discontinuation of therapy, at a time of intestinal remission. In both cases, 15 passages of the cultures were completed over 17 months. Bacterial growth was measured by quantitative polymerase chain reaction, which suggested a generation time of 4 days. Staining with YO-PRO nucleic-acid dye showed characteristic rod-shaped bacteria arranged in chains. Fluorescent in situ hybridization with a T. whipplei-specific oligonucleotide probe, a broad-range bacterial probe, and a nonspecific nucleic-acid stain indicated that all visible bacteria were T. whipplei. Scanning electron microscopy and transmission electron microscopy showed both intracellular and extracellular bacteria. This first isolation of T. whipplei from CSF provides clear evidence of viable bacteria in the central nervous system in individuals with WD, even after prolonged antibiotic therapy.


Subject(s)
Actinomycetales/growth & development , Actinomycetales/isolation & purification , Cerebrospinal Fluid/microbiology , Fibroblasts/microbiology , Whipple Disease/microbiology , Actinomycetales/genetics , Actinomycetales Infections/microbiology , Aged , Benzoxazoles , Cells, Cultured , Central Nervous System Bacterial Infections/microbiology , DNA, Bacterial/analysis , Female , Fluorescent Dyes/metabolism , Humans , In Situ Hybridization, Fluorescence , Male , Microscopy, Electron , Middle Aged , Polymerase Chain Reaction , Quinolinium Compounds , Serial Passage , Staining and Labeling/methods
15.
Arch Otolaryngol Head Neck Surg ; 129(8): 889-93, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12925350

ABSTRACT

OBJECTIVE: To generate in vitro hyaline cartilage from cryogenically preserved human septal chondrocytes in a simulated microgravity environment on a 3-dimensional biodegradable scaffolding material. METHODS: In this experiment, cryogenically frozen chondrocytes were thawed and cultured in a monolayer in serum-based chondrocyte media. They were seeded onto 3-dimensional biopolymer scaffolds in a spinner flask. The seeded constructs were then transferred to a bioreactor (an environment of solid-body rotation) for 6 weeks. Chondrocyte growth and extracellular matrix production in the constructs were confirmed by cell count, cell viability, and histologic analysis and by electron microscopy. RESULTS: Histologic sections stained with hematoxylin-eosin and Alcian blue (for acidic proteoglycans) confirmed the presence of hyaline cartilage in the cartilage constructs. Ultrastructural examination using transmission electron microscopy demonstrated matrix formation and chondrocyte viability. CONCLUSIONS: This study proves that chondrocytes that are cryogenically stored for extended periods can be used to grow cartilage in vitro. Cryogenically preserved chondrocytes retain their ability to grow in tissue culture, redifferentiate, and produce extracellular matrix.


Subject(s)
Chondrocytes/physiology , Extracellular Matrix/physiology , Nasal Septum/cytology , Tissue Engineering/methods , Bioreactors , Cell Culture Techniques , Chondrocytes/cytology , Cryopreservation , Humans , Microscopy, Electron , Weightlessness
16.
Am J Physiol Heart Circ Physiol ; 283(5): H1838-45, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12384461

ABSTRACT

alpha(2A)-Adrenergic receptors (ARs) in the midbrain regulate sympathetic nervous system activity, and both alpha(2A)-ARs and alpha(2C)-ARs regulate catecholamine release from sympathetic nerve terminals in cardiac tissue. Disruption of both alpha(2A)- and alpha(2C)-ARs in mice leads to chronically elevated sympathetic tone and decreased cardiac function by 4 mo of age. These knockout mice have increased mortality, reduced exercise capacity, decreased peak oxygen uptake, and decreased cardiac contractility relative to wild-type controls. Moreover, we observed significant abnormalities in the ultrastructure of cardiac myocytes from alpha(2A)/alpha(2C)-AR knockout mice by electron microscopy. Our results demonstrate that chronic elevation of sympathetic tone can lead to abnormal cardiac function in the absence of prior myocardial injury or genetically induced alterations in myocardial structural or functional proteins. These mice provide a physiologically relevant animal model for investigating the role of the sympathetic nervous system in the development and progression of heart failure.


Subject(s)
Heart Failure/physiopathology , Receptors, Adrenergic, alpha-2/genetics , Sympathetic Nervous System/physiopathology , Animals , Blood Pressure , Disease Models, Animal , Heart Failure/pathology , Heart Rate , Mice , Mice, Inbred C57BL , Mice, Knockout , Myocardial Contraction , Myocardium/pathology , Myocytes, Cardiac/pathology , Physical Exertion
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