35 results on '"Summers TA"'
Search Results
2. RRx-001 Radioprotection: Enhancement of Survival and Hematopoietic Recovery in Gamma-Irradiated Mice.
- Author
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Jurgensen KJ, Skinner WKJ, Oronsky B, Abrouk ND, Graff AE, Landes RD, Culp WE, Summers TA Jr, and Cary LH
- Abstract
The present studies evaluate the in vivo prophylactic radioprotective effects of 1-bromoacetyl-3, 3-dinitroazetidine (RRx-001), a phase III anticancer agent that inhibits c-myc and downregulates CD-47, after total body irradiation (TBI), in lethally and sublethally irradiated CD2F1 male mice. A single dose of RRx-001 was administered by intraperitoneal (IP) injection 24 h prior to a lethal or sublethal radiation dose. When irradiated with 9.35 Gy, the dose lethal to 70% of untreated mice at 30 days (LD
70/30 ), only 33% of mice receiving RRx-001 (10 mg/kg) 24 h prior to total body irradiation (TBI) died by day 30, compared to 67% in vehicle-treated mice. The same pretreatment dose of RRx-001 resulted in a significant dose reduction factor of 1.07. In sublethally TBI mice, bone marrow cellularity was increased at day 14 in the RRx-001-treated mice compared to irradiated vehicle-treated animals. In addition, significantly higher numbers of lymphocytes, platelets, percent hematocrit and percent reticulocytes were observed on days 7 and/or 14 in RRx-001-treated mice. These experiments provide proof of principle that systemic administration of RRx-001 prior to TBI significantly improves overall survival and bone marrow regeneration., Competing Interests: BO and NA are employed by the company of EpicentRx. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jurgensen, Skinner, Oronsky, Abrouk, Graff, Landes, Culp, Summers and Cary.)- Published
- 2021
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3. Predictive Markers Require Thorough Analytic Validation.
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Troxell ML, Fulton RS, Swanson PE, Bellizzi AM, Fitzgibbons PL, Ambaye AB, Haas TS, Goldsmith JD, Loykasek PA, Miller DV, O'Malley D, Qiu J, Salama ME, Schaberg KB, Schwartz RA, Shia J, Summers TA Jr, and Wu Y
- Subjects
- B7-H1 Antigen, Biomarkers, Humans, Immunohistochemistry, Carcinoma, Non-Small-Cell Lung, Lung Neoplasms
- Published
- 2019
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4. Delayed Captopril Administration Mitigates Hematopoietic Injury in a Murine Model of Total Body Irradiation.
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McCart EA, Lee YH, Jha J, Mungunsukh O, Rittase WB, Summers TA Jr, Muir J, and Day RM
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- Acute Radiation Syndrome blood, Acute Radiation Syndrome etiology, Acute Radiation Syndrome mortality, Acute Radiation Syndrome prevention & control, Animals, Blood Cell Count, Cell Cycle drug effects, Cell Cycle radiation effects, Cytokines metabolism, Disease Models, Animal, Dose-Response Relationship, Drug, Dose-Response Relationship, Radiation, Gene Expression Regulation drug effects, Gene Expression Regulation radiation effects, Hematopoietic Stem Cells drug effects, Hematopoietic Stem Cells metabolism, Hematopoietic Stem Cells radiation effects, Inflammation Mediators metabolism, Mice, Radiation Dosage, Radiation Exposure, Time-to-Treatment, Angiotensin-Converting Enzyme Inhibitors administration & dosage, Captopril administration & dosage, Hematopoiesis drug effects, Hematopoiesis radiation effects, Radiation-Protective Agents administration & dosage, Whole-Body Irradiation adverse effects
- Abstract
The increasing potential for accidental radiation exposure from either nuclear accidents or terrorist activities has escalated the need for radiation countermeasure development. We previously showed that a 30-day course of high-dose captopril, an ACE inhibitor, initiated 1-4 h after total body irradiation (TBI), improved Hematopoietic Acute Radiation Syndrome (H-ARS) and increased survival in mice. However, because of the time likely required for the deployment of a stockpiled radiation countermeasure to a radiation mass casualty site, there is a need for therapies that can be administered 24-48 hours after initial exposure. Using C57BL/6 mice exposed to an LD
50-80/30 of60 Co TBI (7.75-7.9 Gy, 0.615 Gy/min), we show that low-dose captopril administration, initiated as late as 48 h post-TBI and continued for 14 days, significantly enhanced overall survival similarly to high-dose, rapid administration. Captopril treatment did not affect radiation-induced cell cycle arrest genes or the immediate loss of hematopoietic precursors. Reduced mortality was associated with the recovery of bone marrow cellularity and mature blood cell recovery at 21-30 days post-irradiation. Captopril reduced radiation-induced cytokines EPO, G-CSF, and SAA in the plasma. Finally, delayed captopril administration mitigated brain micro-hemorrhage at 21 days post-irradiation. These data indicate that low dose captopril administered as late as 48 h post-TBI for only two weeks improves survival that is associated with hematopoietic recovery and reduced inflammatory response. These data suggest that captopril may be an ideal countermeasure to mitigate H-ARS following accidental radiation exposure.- Published
- 2019
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5. Captopril mitigates splenomegaly and myelofibrosis in the Gata1 low murine model of myelofibrosis.
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Corey SJ, Jha J, McCart EA, Rittase WB, George J, Mattapallil JJ, Mehta H, Ognoon M, Bylicky MA, Summers TA, and Day RM
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- Administration, Oral, Animals, Bone Marrow drug effects, Bone Marrow metabolism, Bone Marrow pathology, Collagen antagonists & inhibitors, Collagen genetics, Collagen metabolism, Disease Models, Animal, Drinking Water administration & dosage, Drug Repositioning, Female, GATA1 Transcription Factor deficiency, Gene Expression, Male, Megakaryocytes drug effects, Megakaryocytes metabolism, Megakaryocytes pathology, Mice, Mice, Knockout, Primary Myelofibrosis genetics, Primary Myelofibrosis metabolism, Primary Myelofibrosis pathology, Reticulin antagonists & inhibitors, Reticulin genetics, Reticulin metabolism, Splenomegaly genetics, Splenomegaly metabolism, Splenomegaly pathology, Angiotensin-Converting Enzyme Inhibitors pharmacology, Antineoplastic Agents pharmacology, Captopril pharmacology, GATA1 Transcription Factor genetics, Primary Myelofibrosis drug therapy, Splenomegaly drug therapy
- Abstract
Allogeneic stem cell transplantation is currently the only curative therapy for primary myelofibrosis (MF), while the JAK2 inhibitor, ruxolitinib. Has been approved only for palliation. Other therapies are desperately needed to reverse life-threatening MF. However, the cell(s) and cytokine(s) that promote MF remain unclear. Several reports have demonstrated that captopril, an inhibitor of angiotensin-converting enzyme that blocks the production of angiotensin II (Ang II), mitigates fibrosis in heart, lung, skin and kidney. Here, we show that captopril can mitigate the development of MF in the Gata1
low mouse model of primary MF. Gata1low mice were treated with 79 mg/kg/d captopril in the drinking water from 10 to 12 months of age. At 13 months of age, bone marrows were examined for fibrosis, megakaryocytosis and collagen expression; spleens were examined for megakaryocytosis, splenomegaly and collagen expression. Treatment of Gata1low mice with captopril in the drinking water was associated with normalization of the bone marrow cellularity; reduced reticulin fibres, splenomegaly and megakaryocytosis; and decreased collagen expression. Our findings suggest that treating with the ACE inhibitors captopril has a significant benefit in overcoming pathological changes associated with MF., (© 2018 Virginia Commonwealth University. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)- Published
- 2018
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6. Midkine and pleiotrophin concentrations in needle biopsies of breast and lung masses.
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Giamanco NM, Jee YH, Wellstein A, Shriver CD, Summers TA, and Baron J
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- Breast Neoplasms pathology, Female, Humans, Lung Neoplasms pathology, Male, Middle Aged, Midkine, Biopsy, Fine-Needle methods, Breast Neoplasms diagnosis, Carrier Proteins metabolism, Cytokines metabolism, Intercellular Signaling Peptides and Proteins metabolism, Lung Neoplasms diagnosis
- Abstract
Background/objective: Midkine (MDK) and pleiotrophin (PTN) are two closely related heparin-binding growth factors which are overexpressed in a wide variety of human cancers. We hypothesized that the concentrations of these factors in washout of biopsy needles would be higher in breast and lung cancer than in benign lesions., Methods: Seventy subjects underwent pre-operative core needle biopsies of 78 breast masses (16 malignancies). In 11 subjects, fine needle aspiration was performed ex vivo on 7 non-small cell lung cancers and 11 normal lung specimens within surgically excised lung tissue. The biopsy needle was washed with buffer for immunoassay., Results: The MDK/DNA and the PTN/DNA ratio in most of the malignant breast masses were similar to the ratios in benign masses except one lobular carcinoma in situ (24-fold higher PTN/DNA ratio than the average benign mass). The MDK/DNA and PTN/DNA ratio were similar in most malignant and normal lung tissue except one squamous cell carcinoma (38-fold higher MDK/DNA ratio than the average of normal lung tissue)., Conclusions: Both MDK and PTN are readily measurable in washout of needle biopsy samples from breast and lung masses and levels are highly elevated only in a specific subset of these malignancies.
- Published
- 2017
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7. RRx-001 Priming of PD-1 Inhibition in the Treatment of Small Cell Carcinoma of the Vagina: A Rare Gynecological Tumor.
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Brzezniak C, Oronsky B, Trepel J, Summers TA Jr, Cabrales P, Lee MJ, Day R, Jha S, Caroen S, Zeman K, Ferry L, Harmer C, Oronsky N, Lybeck M, Lybeck HE, Brown JF, Reid TR, and Carter CA
- Abstract
Small cell carcinoma of the vagina is rare, so rare in fact that the total number reported in English-language journals is less than 30. Due to this extremely low incidence, no specific treatment guidelines have been established, and most of what is clinically known is derived from a handful of single case reports. However, as befitting its highly aggressive histologic features, which are reminiscent of small cell lung cancer (SCLC), first-line treatment is modeled after SCLC. Herein is reported the case of a 51-year-old African-American patient with metastatic biopsy-proven small cell carcinoma of the vagina that progressed through multiple therapies: first-line cisplatin and etoposide (making it platinum-resistant) and radiotherapy, followed by the tumor macrophage-stimulating agent RRx-001 in a clinical trial called QUADRUPLE THREAT, which per protocol preceded a mandated rechallenge with cisplatin and etoposide. RECIST v.1.1 tumor progression on both RRx-001 and cisplatin/etoposide was accompanied by central necrosis in several of the enlarged lymph nodes and hepatic metastases, which may have been evidence of pseudoprogression, accounting for her ongoing longer-than-expected survival, since the necrotic tissue may have primed the activity of the PD-1 inhibitor. The lack of response to RRx-001 is hypothesized to have correlated with sparse tumor macrophage infiltration, seen on pre- and post-treatment biopsies, since the mechanism of action of RRx-001 relates to stimulation of tumor-associated macrophages.
- Published
- 2017
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8. RRx-001: a systemically non-toxic M2-to-M1 macrophage stimulating and prosensitizing agent in Phase II clinical trials.
- Author
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Oronsky B, Paulmurugan R, Foygel K, Scicinski J, Knox SJ, Peehl D, Zhao H, Ning S, Cabrales P, Summers TA Jr, Reid TR, Fitch WL, Kim MM, Trepel JB, Lee MJ, Kesari S, Abrouk ND, Day RM, Oronsky A, Ray CM, and Carter CA
- Subjects
- Animals, Antineoplastic Agents adverse effects, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Azetidines adverse effects, Azetidines pharmacology, Cell Death drug effects, Drug Resistance, Neoplasm, Humans, Macrophages metabolism, Neoplasms pathology, Nitro Compounds adverse effects, Nitro Compounds pharmacology, Azetidines therapeutic use, Macrophages drug effects, Neoplasms drug therapy, Nitro Compounds therapeutic use
- Abstract
Introduction: According to Hanahan and Weinberg, cancer manifests as six essential physiologic hallmarks: (1) self-sufficiency in growth signals, (2) insensitivity to growth-inhibitory signals, (3) evasion of programmed cell death, (4) limitless replicative potential, (5) sustained angiogenesis, and (6) invasion and metastasis. As a facilitator of these traits as well as immunosuppression and chemoresistance, the presence of tumor-associated macrophages (TAMs) may serve as the seventh hallmark of cancer. Anticancer agents that successfully reprogram TAMs to target rather than support tumor cells may hold the key to better therapeutic outcomes. Areas covered: This article summarizes the characteristics of the macrophage-stimulating agent RRx-001, a molecular iconoclast, sourced from the aerospace industry, with a particular emphasis on the cell-to-cell transfer mechanism of action (RBCs to TAMs) underlying its antitumor activity as well as its chemo and radioprotective properties, consolidated from various preclinical and clinical studies. Expert opinion: RRx-001 is macrophage-stimulating agent with the potential to synergize with chemotherapy, radiotherapy and immunotherapy while simultaneously protecting normal tissues from their cytotoxic effects. Given the promising indications of activity in multiple tumor types and these normal tissue protective properties, RRx-001 may be used to treat a broad spectrum of malignancies, if it is approved in the future.
- Published
- 2017
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9. Multispectral Imaging Analysis of Circulating Tumor Cells in Negatively Enriched Peripheral Blood Samples.
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Miller B, Lustberg M, Summers TA, and Chalmers JJ
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- Biomarkers, Tumor genetics, Biomarkers, Tumor immunology, Biomarkers, Tumor metabolism, Breast Neoplasms blood, Breast Neoplasms immunology, Breast Neoplasms pathology, Carbocyanines chemistry, Cell Count instrumentation, Cell Count methods, Cell Line, Tumor, Epithelial Cell Adhesion Molecule genetics, Epithelial Cell Adhesion Molecule immunology, Epithelial Cell Adhesion Molecule metabolism, Female, Fluorescent Dyes chemistry, Humans, Hydrazines chemistry, Image Processing, Computer-Assisted statistics & numerical data, Indoles chemistry, Keratins genetics, Keratins immunology, Keratins metabolism, Leukocyte Common Antigens genetics, Leukocyte Common Antigens immunology, Leukocyte Common Antigens metabolism, Leukocytes, Mononuclear cytology, Leukocytes, Mononuclear immunology, Leukocytes, Mononuclear metabolism, Liquid Crystals, Neoplastic Cells, Circulating immunology, Neoplastic Cells, Circulating metabolism, Optical Imaging statistics & numerical data, Succinimides chemistry, Breast Neoplasms diagnosis, Image Processing, Computer-Assisted methods, Neoplastic Cells, Circulating pathology, Optical Imaging methods, Software
- Abstract
A variety of biomarkers are present on cells in peripheral blood of patients with a variety of disorders, including solid tumor malignancies. While rare, characterization of these cells for specific protein levels with the advanced technology proposed, will lead to future validation studies of blood samples as "liquid biopsies" for the evaluation of disease status and therapeutic response. While circulating tumor cells (CTCs) have been isolated in the blood samples of patients with solid tumors, the exact role of CTCs as clinically useful predictive markers is still debated. Current commercial technology has significant bias in that a positive selection technology is used that preassumes specific cell surface markers (such as EpCAM) are present on CTCs. However, CTCs with low EpCAM expression have been experimentally demonstrated to be more likely to be missed by this method. In contrast, this application uses a previously developed, technology that performs a purely negative enrichment methodology on peripheral blood, yielding highly enriched blood samples that contain CTCs as well as other, undefined cell types. The focus of this contribution is the use of multispectral imaging of epifluorescent, microscopic images of these enriched cells in order to help develop clinically relevant liquid biopsies from peripheral blood samples.
- Published
- 2017
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10. Heterogeneous atypical cell populations are present in blood of metastatic breast cancer patients.
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Lustberg MB, Balasubramanian P, Miller B, Garcia-Villa A, Deighan C, Wu Y, Carothers S, Berger M, Ramaswamy B, Macrae ER, Wesolowski R, Layman RM, Mrozek E, Pan X, Summers TA, Shapiro CL, and Chalmers JJ
- Subjects
- Adult, Aged, Antigens, CD blood, Antigens, CD metabolism, Antigens, Differentiation, Myelomonocytic blood, Antigens, Differentiation, Myelomonocytic metabolism, Antigens, Neoplasm blood, Antigens, Neoplasm metabolism, Biomarkers, Tumor metabolism, Breast Neoplasms metabolism, Breast Neoplasms pathology, Cell Adhesion Molecules blood, Cell Adhesion Molecules metabolism, Cell Line, Tumor, Epithelial Cell Adhesion Molecule, ErbB Receptors blood, ErbB Receptors metabolism, Female, Flow Cytometry, Humans, Immunohistochemistry, Keratin-18 blood, Keratin-18 metabolism, Keratin-19 blood, Keratin-19 metabolism, Keratin-8 blood, Keratin-8 metabolism, Leukocyte Common Antigens blood, Leukocyte Common Antigens metabolism, MCF-7 Cells, Microscopy, Confocal, Middle Aged, Neoplasm Metastasis, Prognosis, Prospective Studies, Vimentin blood, Vimentin metabolism, Biomarkers, Tumor blood, Breast Neoplasms blood, Neoplastic Cells, Circulating metabolism
- Abstract
Introduction: Circulating tumor cells (CTCs) are commonly isolated from the blood by targeting the epithelial cell adhesion molecule (EpCAM) through positive selection. However, EpCAM can be downregulated during metastatic progression, or it can be initially not present. We designed the present prospective trial to characterize CTCs as well as other circulating cell populations in blood samples from women with metastatic breast cancer without EpCAM-dependent enrichment and/or isolation technology., Methods: A total of 32 patients with metastatic breast cancer were enrolled, and blood samples were processed using a previously described negative depletion immunomagnetic methodology. Samples from healthy volunteers were run as controls (n = 5). Multistep sequential labeling was performed to label and fix cell-surface markers followed by permeabilization for cytokeratins (CK) 8, 18 and 19. Multiparametric flow cytometry (FCM) analysis was conducted using a BD LSR II flow cytometer or a BD FACSAria II or FACSAria III cell sorter. Immunocytochemical staining on postenrichment specimens for DAPI, EpCAM, CD45, CK, epidermal growth factor receptor and vimentin was performed. Expression of these markers was visualized using confocal microscopy (CM)., Results: CD45-negative/CK-positive (CD45- CK+) populations with EpCAM + and EpCAM - expression were identified with both FCM and CM from the negatively enriched patient samples. In addition, EpCAM + and EpCAM - populations that were CK + and coexpressing the pan-hematopoietic marker CD45 were also noted. There were more CK + EpCAM - events/ml than CK + EpCAM + events/ml in both the CD45- and CD45+ fractions (both statistically significant at P ≤ 0.0005). The number of CK + CD45- and CK + CD45+ events per milliliter in blood samples (regardless of EpCAM status) was higher in patient samples than in normal control samples (P ≤ 0.0005 and P ≤ 0.026, respectively). Further, a significant fraction of the CK + CD45+ events also expressed CD68, a marker associated with tumor-associated macrophages. Higher levels of CD45-CK + EpCAM - were associated with worse overall survival (P = 0.0292)., Conclusions: Metastatic breast cancer patients have atypical cells that are CK + EpCAM - circulating in their blood. Because a substantial number of these patients do not have EpCAM + CTCs, additional studies are needed to evaluate the role of EpCAM - circulating cells as a prognostic and predictive marker.
- Published
- 2014
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11. The tug sign: an endoscopic feature of eosinophilic esophagitis.
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Moawad FJ, Robinson CL, Veerappan GR, Summers TA, Maydonovitch CL, and Wong RKh
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- Adult, Female, Humans, Male, Phenotype, Eosinophilic Esophagitis diagnosis, Esophagoscopy
- Published
- 2013
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12. Splenic manifestations of chronic autoimmune disorder: a report of five cases with histiocytic necrotizing change in four cases.
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Auerbach A, Summers TA, Zhang B, and Aguilera NS
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- Adult, Arthritis, Rheumatoid immunology, Arthritis, Rheumatoid metabolism, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes immunology, Chronic Disease, Dendritic Cells metabolism, Dendritic Cells pathology, Female, Herpesvirus 4, Human genetics, Histiocytic Necrotizing Lymphadenitis immunology, Histiocytic Necrotizing Lymphadenitis metabolism, Humans, Lupus Erythematosus, Systemic immunology, Lupus Erythematosus, Systemic metabolism, Male, Middle Aged, Spleen metabolism, Spleen pathology, Arthritis, Rheumatoid pathology, Histiocytic Necrotizing Lymphadenitis pathology, Lupus Erythematosus, Systemic pathology
- Abstract
Aims: Autoimmune diseases (AD) are associated with lymphadenopathy and splenomegaly. Changes in the spleen have not been characterized completely in AD; we describe splenectomy specimens from five patients with chronic AD, highlighting the presence of necrotizing histiocytosis., Methods and Results: Of the patients (three males and two females; mean 40 years), four had systemic lupus erythematosus; one had rheumatoid arthritis. All had moderate splenomegaly (213-803 g, mean 421 g). Four cases exhibited necrosis with apoptosis and karyorrhectic debris occurring in the white pulp and minimal acute inflammation; one showed florid follicular hyperplasia. Splenic involvement ranged from focal to extensive. Plasma cells were negative for IgG4. Haematoxylin bodies were not identified. Stains for infectious organisms were negative. Immunohistochemical studies showed that lymphocytes surrounding the necrosis were a mixture of CD4(+) and CD8(+) T cells; CD123-positive plasmacytoid dendritic cells were not present, and staining for kappa and lambda light chains showed no clonality. 16S rDNA PCR was performed; no amplification was seen in three of four cases tested for bacteria specific rDNA. Epstein-Barr virus-encoded RNA (EBER) in situ hybridization studies highlighted rare positive cells in four cases., Conclusions: Splenomegaly in AD is thought to be hyperplasic, but we present four cases showing histiocytic necrosis, a finding which should be considered part of the spectrum of AD in the spleen., (© 2013 John Wiley & Sons Ltd.)
- Published
- 2013
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13. Colorectal cancer stem cells as biomarkers: where it all starts?
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Avital I, Summers TA, Steele SR, Waldman S, Nissan A, Bilchik AJ, Protic M, Man YG, Brücher BL, and Stojadinovic A
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- Antineoplastic Agents pharmacology, Humans, Mutation drug effects, United States epidemiology, Biomarkers, Tumor analysis, Colorectal Neoplasms drug therapy, Colorectal Neoplasms epidemiology, Colorectal Neoplasms genetics, Molecular Targeted Therapy, Neoplastic Stem Cells
- Published
- 2013
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14. Evidence-based Guidelines for Precision Risk Stratification-Based Screening (PRSBS) for Colorectal Cancer: Lessons learned from the US Armed Forces: Consensus and Future Directions.
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Avital I, Langan RC, Summers TA, Steele SR, Waldman SA, Backman V, Yee J, Nissan A, Young P, Womeldorph C, Mancusco P, Mueller R, Noto K, Grundfest W, Bilchik AJ, Protic M, Daumer M, Eberhardt J, Man YG, Brücher BL, and Stojadinovic A
- Abstract
Colorectal cancer (CRC) is the third most common cause of cancer-related death in the United States (U.S.), with estimates of 143,460 new cases and 51,690 deaths for the year 2012. Numerous organizations have published guidelines for CRC screening; however, these numerical estimates of incidence and disease-specific mortality have remained stable from years prior. Technological, genetic profiling, molecular and surgical advances in our modern era should allow us to improve risk stratification of patients with CRC and identify those who may benefit from preventive measures, early aggressive treatment, alternative treatment strategies, and/or frequent surveillance for the early detection of disease recurrence. To better negotiate future economic constraints and enhance patient outcomes, ultimately, we propose to apply the principals of personalized and precise cancer care to risk-stratify patients for CRC screening (Precision Risk Stratification-Based Screening, PRSBS). We believe that genetic, molecular, ethnic and socioeconomic disparities impact oncological outcomes in general, those related to CRC, in particular. This document highlights evidence-based screening recommendations and risk stratification methods in response to our CRC working group private-public consensus meeting held in March 2012. Our aim was to address how we could improve CRC risk stratification-based screening, and to provide a vision for the future to achieving superior survival rates for patients diagnosed with CRC.
- Published
- 2013
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15. Multiparameter analysis, including EMT markers, on negatively enriched blood samples from patients with squamous cell carcinoma of the head and neck.
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Balasubramanian P, Lang JC, Jatana KR, Miller B, Ozer E, Old M, Schuller DE, Agrawal A, Teknos TN, Summers TA Jr, Lustberg MB, Zborowski M, and Chalmers JJ
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- Adult, Aged, Antigens, Neoplasm metabolism, Carcinoma, Squamous Cell metabolism, Cell Adhesion Molecules metabolism, Cell Line, Tumor, Epithelial Cell Adhesion Molecule, Female, Head and Neck Neoplasms metabolism, Humans, Leukocyte Common Antigens metabolism, Male, Middle Aged, Biomarkers, Tumor metabolism, Carcinoma, Squamous Cell blood, Carcinoma, Squamous Cell pathology, Epithelial-Mesenchymal Transition, Head and Neck Neoplasms blood, Head and Neck Neoplasms pathology, Neoplastic Cells, Circulating pathology
- Abstract
Epithelial to mesenchymal transition (EMT) has been hypothesized as a mechanism by which cells change phenotype during carcinogenesis, as well as tumor metastasis. Whether EMT is involved in cancer metastasis has a specific, practical impact on the field of circulating tumor cells (CTCs). Since the generally accepted definition of a CTC includes the expression of epithelial surface markers, such as EpCAM, if a cancer cell loses its epithelial surface markers (which is suggested in EMT), it will not be separated and/or identified as a CTC. We have developed, and previously reported on the use of, a purely negative enrichment technology enriching for CTCs in the blood of squamous cell carcinoma of the head and neck (SCCHN). This methodology does not depend on the expression of surface epithelial markers. Using this technology, our initial data on SCCHN patient blood indicates that the presence of CTCs correlates with worse disease-free survival. Since our enrichment is not dependent on epithelial markers, we have initiated investigation of the presence of mesenchymal markers in these CTC cells to include analysis of: vimentin, epidermal growth factor receptor, N-cadherin, and CD44. With the aid of confocal microscopy, we have demonstrated not only presumed CTCs that express and/or contain: a nucleus, cytokeratins, vimentin, and either EGFR, CD44, or N-cadherin, but also cells that contain all of the aforementioned proteins except cytokeratins, suggesting that the cells have undergone the EMT process. We suggest that our negative depletion enrichment methodology provides a more objective approach in identifying and evaluating CTCs, as opposed to positive selection approaches, as it is not subjective to a selection bias and can be tailored to accommodate a variety of cytoplasmic and surface markers which can be evaluated to identify a multitude of phenotypic patterns within CTCs from individual patients, including so-called EMT as presented here.
- Published
- 2012
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16. Gray zone lymphoma: chromosomal aberrations with immunophenotypic and clinical correlations.
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Eberle FC, Salaverria I, Steidl C, Summers TA Jr, Pittaluga S, Neriah SB, Rodriguez-Canales J, Xi L, Ylaya K, Liewehr D, Dunleavy K, Wilson WH, Hewitt SM, Raffeld M, Gascoyne RD, Siebert R, and Jaffe ES
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Gene Expression Regulation, Neoplastic, Hodgkin Disease classification, Hodgkin Disease immunology, Hodgkin Disease pathology, Humans, Immunohistochemistry, Immunophenotyping, In Situ Hybridization, Fluorescence, Lymphoma classification, Lymphoma immunology, Lymphoma pathology, Lymphoma, Large B-Cell, Diffuse classification, Lymphoma, Large B-Cell, Diffuse immunology, Lymphoma, Large B-Cell, Diffuse pathology, Male, Mediastinal Neoplasms classification, Mediastinal Neoplasms immunology, Mediastinal Neoplasms pathology, Middle Aged, Prognosis, Young Adult, Biomarkers, Tumor analysis, Chromosome Aberrations, Hodgkin Disease genetics, Lymphoma genetics, Lymphoma, Large B-Cell, Diffuse genetics, Mediastinal Neoplasms genetics
- Abstract
The term gray zone lymphoma has been applied to tumors that demonstrate transitional morphologic and immunophenotypic features between classical Hodgkin's lymphoma and diffuse large B-cell lymphoma, especially primary mediastinal large B-cell lymphoma. Histopathological and genetic data are limited for these unusual cases. We analyzed cases of gray zone lymphoma (n=27), mediastinal composite lymphoma (n=3) and mediastinal synchronous/metachronous lymphoma (n=3) by morphology, immunophenotyping and fluorescence in situ hybridization. Mediastinal involvement was assured in 24/33 patients (73%). The patient cohort showed a male predominance (M:F ratio; 20:13) and a median age of 32 years (range, 16-91 years). Patients with mediastinal disease were significantly younger (median age: 29.5 years) than patients presenting without evident mediastinal disease (median age: 55 years). Gains including amplifications in 2p16.1 (REL/BCL11A locus) were observed in 33% of all patients, whereas alterations affecting the JAK2/PDL2 locus in 9p24.1 were present in 55%. Further studies revealed rearrangement of the CIITA locus at 16p13.13 in 8/30 cases (27%) and 7/26 cases (27%) demonstrated gains of 8q24 (MYC). Genetic aberrations involving 2p16.1, 9p24.1 and 8q24 showed a higher incidence in cases with evident mediastinal involvement. However, this was not statistically significant when compared with cases without known mediastinal involvement. Twelve of the 27 cases of gray zone lymphoma were morphologically more reminiscent of classical Hodgkin's lymphoma, whereas the other gray zone lymphomas presented with morphological features more closely resembling large B-cell lymphoma. Both morphological groups of gray zone lymphoma were similarly positive for Cyclin E (75 and 93%) and p63 (50 and 53%, respectively) expression. These findings further support a close relationship between gray zone lymphoma, classical Hodgkin's lymphoma and primary mediastinal large B-cell lymphoma, and suggest that some cases of gray zone lymphoma without mediastinal disease may share similar genetic alterations.
- Published
- 2011
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17. Hairy cell leukemia diagnostic criteria and differential diagnosis.
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Summers TA and Jaffe ES
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- Bone Marrow pathology, Diagnosis, Differential, Humans, Leukemia, Hairy Cell pathology, Lymph Nodes pathology, Lymphoma, B-Cell classification, Leukemia, Hairy Cell diagnosis
- Abstract
Hairy cell leukemia (HCL) is a disease with distinctive clinical findings, as well as a unique morphology and immunophenotype. These features typically allow for a reliable and reproducible diagnosis in nearly all situations. However, certain morphological features of HCL, such as villous cytoplasmic projections or characteristic tissue specific infiltrative patterns, including red pulp expansion with pseudosinuses, may be seen in other B-cell lymphoproliferative disorders. A methodical and thorough approach evaluating the clinical, cytological, histological, architectural, and immunophenotypic features is described and will aid in rendering the appropriate diagnosis. This is paramount as current data indicate that hairy cell leukemia - variant and other splenic B-cell lymphomas must be distinguished from HCL, as the response to therapy differs in these disorders.
- Published
- 2011
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18. Consensus recommendations for advancing breast cancer: risk identification and screening in ethnically diverse younger women.
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Stojadinovic A, Summers TA, Eberhardt J, Cerussi A, Grundfest W, Peterson CM, Brazaitis M, Krupinski E, and Freeman H
- Abstract
A need exists for a breast cancer risk identification paradigm that utilizes relevant demographic, clinical, and other readily obtainable patient-specific data in order to provide individualized cancer risk assessment, direct screening efforts, and detect breast cancer at an early disease stage in historically underserved populations, such as younger women (under age 40) and minority populations, who represent a disproportionate number of military beneficiaries. Recognizing this unique need for military beneficiaries, a consensus panel was convened by the USA TATRC to review available evidence for individualized breast cancer risk assessment and screening in young (< 40), ethnically diverse women with an overall goal of improving care for military beneficiaries. In the process of review and discussion, it was determined to publish our findings as the panel believes that our recommendations have the potential to reduce health disparities in risk assessment, health promotion, disease prevention, and early cancer detection within and in other underserved populations outside of the military. This paper aims to provide clinicians with an overview of the clinical factors, evidence and recommendations that are being used to advance risk assessment and screening for breast cancer in the military.
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- 2011
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19. The small cell variant of anaplastic large cell lymphoma.
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Summers TA and Moncur JT
- Subjects
- Diagnosis, Differential, Humans, Ki-1 Antigen metabolism, Lymphoma, Large-Cell, Anaplastic metabolism, Lymphocytes pathology, Lymphoma, Large-Cell, Anaplastic pathology
- Abstract
Anaplastic large cell lymphomas constitute a heterogeneous group of hematopoietic neoplasms that are characterized by immunopositivity for CD30 and the presence, in varying degrees, of large, pleomorphic "hallmark" cells. Primary systemic anaplastic lymphoma kinase-positive anaplastic large cell lymphomas are a subset of this group. Numerous heterogeneous histomorphologic patterns have been described in anaplastic lymphoma kinase-positive anaplastic large cell lymphomas, and all patterns tend to have a better prognosis than that found in anaplastic lymphoma kinase-negative cases. We provide a short review of the small cell variant of anaplastic large cell lymphoma to facilitate the diagnosis of this difficult-to-recognize entity, which may be confused with reactive processes, commonly presents with disseminated disease, and pursues an aggressive clinical course.
- Published
- 2010
- Full Text
- View/download PDF
20. Cutaneous involvement in the lymphoepithelioid variant of peripheral T-cell lymphoma, unspecified (Lennert lymphoma). Report of a case and review of the literature.
- Author
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Summers TA Jr, Rush W, Aguilera N, and Lupton G
- Subjects
- Antigens, CD biosynthesis, Antineoplastic Combined Chemotherapy Protocols, Biomarkers, Tumor analysis, Humans, Immunohistochemistry, Immunophenotyping, Lymphoma, T-Cell, Peripheral drug therapy, Lymphoma, T-Cell, Peripheral immunology, Male, Middle Aged, Polymerase Chain Reaction, Skin Neoplasms drug therapy, Skin Neoplasms immunology, T-Lymphocytes immunology, Lymphoma, T-Cell, Peripheral pathology, Skin Neoplasms pathology, T-Lymphocytes pathology
- Abstract
Lennert lymphoma (LL), or the lymphoepithelioid variant of peripheral T-cell lymphoma, is an uncommon entity with rarely seen or reported presentations in the skin. Cutaneous involvement of LL has been characterized by asymptomatic, non-ulcerated, red to violet papules, nodules and small plaques (less than 5 cm) on the trunk and extremities. Histologically, there are localized cellular lymphoid infiltrates in the dermis that tend to localize around blood vessels or skin appendages. Key to the diagnosis of LL is the presence of epithelioid histiocytes and atypical small lymphoid cells without increased vascularity or epidermotropism. Immunophenotyping shows a dense monoclonal T-cell population commonly associated with aberrant loss of T-cell-associated antigens. T-cell receptor gene rearrangements are also identified. Patients typically present with advanced stage and have a low 5-year survival. Herein, we present a case of cutaneous involvement by LL at the time of initial presentation that persisted after initiation of chemotherapy and was finally verified as secondary cutaneous involvement of LL 1 year later histologically, immunophenotypically and by T-cell receptor gene rearrangement studies.
- Published
- 2009
- Full Text
- View/download PDF
21. Lupus mastitis: a clinicopathologic review and addition of a case.
- Author
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Summers TA Jr, Lehman MB, Barner R, and Royer MC
- Subjects
- Adipose Tissue pathology, Adult, Autoimmune Diseases pathology, Breast Diseases pathology, Dermis pathology, Diagnosis, Differential, Epidermis pathology, Female, Humans, Male, Middle Aged, Necrosis, Panniculitis, Lupus Erythematosus diagnostic imaging, Panniculitis, Lupus Erythematosus surgery, Radiography, Recurrence, Sex Characteristics, Young Adult, Panniculitis, Lupus Erythematosus pathology
- Abstract
Lupus mastitis (LM) is a rare presentation of lupus erythematosus profundus or lupus panniculitis, an unusual and rare clinical variant of lupus erythematosus itself in which the inflammatory reaction occurs primarily in the deep subcutaneous adipose. Although not required for diagnosis, essentially all cases of LM present with systemic or discoid lupus. The etiology is uncertain. Histologically it is defined by a lymphocytic lobular panniculitis and a characteristic hyaline sclerosis of the adipose tissue. Treatment is primarily medical due to exacerbation of disease by surgical intervention. A high index of suspicion, and familiarity of the histologic findings, is therefore required to make an accurate diagnosis and prevent further unwarranted diagnostic procedures. Herein, we provide a literature-based review of the clinical, radiologic, and pathologic findings of LM and its treatment and prognosis with the addition of a case for the literature.
- Published
- 2009
- Full Text
- View/download PDF
22. Critical policy challenges in the third decade of the HIV/AIDS epidemic.
- Author
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Kates J, Sorian R, Crowley JS, and Summers TA
- Subjects
- Acquired Immunodeficiency Syndrome epidemiology, Acquired Immunodeficiency Syndrome prevention & control, Disease Outbreaks economics, Drug Costs, Female, Financing, Government, Global Health, HIV Infections prevention & control, Health Care Rationing, Health Education, Health Services Accessibility, Humans, International Cooperation, Leadership, Male, United States epidemiology, Disease Outbreaks prevention & control, HIV Infections epidemiology, Health Policy
- Abstract
Numerous policy challenges continue to face the United States in the third decade of the HIV/AIDS pandemic, in both the health and foreign policy arenas. They include long-standing questions about care, treatment, prevention, and research, as well as new ones introduced by the changing nature of the epidemic itself and the need to balance demands for limited resources. These challenges concern the United States not only in its role as a world leader in combating a global epidemic, but in its decisions and focus at home, where the epidemic continues to take a toll.
- Published
- 2002
- Full Text
- View/download PDF
23. Expression and distribution of leptospiral outer membrane components during renal infection of hamsters.
- Author
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Barnett JK, Barnett D, Bolin CA, Summers TA, Wagar EA, Cheville NF, Hartskeerl RA, and Haake DA
- Subjects
- Animals, Antibodies, Bacterial immunology, Antigens, Surface immunology, Cricetinae, Female, Immunoenzyme Techniques, Kidney pathology, Kidney Diseases immunology, Kidney Diseases pathology, Leptospira immunology, Leptospirosis blood, Leptospirosis immunology, Leptospirosis pathology, Lipoproteins metabolism, Male, Mesocricetus, Mice, Porins metabolism, Virulence, Bacterial Outer Membrane Proteins metabolism, Kidney Diseases microbiology, Leptospirosis microbiology
- Abstract
The outer membrane of pathogenic Leptospira species grown in culture media contains lipopolysaccharide (LPS), a porin (OmpL1), and several lipoproteins, including LipL36 and LipL41. The purpose of this study was to characterize the expression and distribution of these outer membrane antigens during renal infection. Hamsters were challenged with host-derived Leptospira kirschneri to generate sera which contained antibodies to antigens expressed in vivo. Immunoblotting performed with sera from animals challenged with these host-derived organisms demonstrated reactivity with OmpL1, LipL41, and several other proteins but not with LipL36. Although LipL36 is a prominent outer membrane antigen of cultivated L. kirschneri, its expression also could not be detected in infected hamster kidney tissue by immunohistochemistry, indicating that expression of this protein is down-regulated in vivo. In contrast, LPS, OmpL1, and LipL41 were demonstrated on organisms colonizing the lumen of proximal convoluted renal tubules at both 10 and 28 days postinfection. Tubular epithelial cells around the luminal colonies had fine granular cytoplasmic LPS. When the cellular inflammatory response was present in the renal interstitium at 28 days postinfection, LPS and OmpL1 were also detectable within interstitial phagocytes. These data establish that outer membrane components expressed during infection have roles in the induction and persistence of leptospiral interstitial nephritis.
- Published
- 1999
- Full Text
- View/download PDF
24. Characterization of leptospiral outer membrane lipoprotein LipL36: downregulation associated with late-log-phase growth and mammalian infection.
- Author
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Haake DA, Martinich C, Summers TA, Shang ES, Pruetz JD, McCoy AM, Mazel MK, and Bolin CA
- Subjects
- Amino Acid Sequence, Animals, Anti-Bacterial Agents pharmacology, Antibodies, Bacterial blood, Base Sequence, Cricetinae, Down-Regulation, Female, Leptospira growth & development, Leptospira immunology, Male, Mesocricetus, Mice, Molecular Sequence Data, Octoxynol pharmacology, Solubility, Bacterial Outer Membrane Proteins genetics, Leptospira chemistry, Leptospirosis metabolism, Peptides
- Abstract
We report the cloning of the gene encoding a 36-kDa leptospiral outer membrane lipoprotein, designated LipL36. We obtained the N-terminal amino acid sequence of a staphylococcal V8 proteolytic-digest fragment in order to design an oligonucleotide probe. A Lambda-Zap II library containing EcoRI fragments of Leptospira kirschneri DNA was screened, and a 2.3-kb DNA fragment which contained the entire structural lipL36 gene was identified. Several lines of evidence indicate that LipL36 is lipid modified in a manner similar to that of LipL41, a leptospiral outer membrane lipoprotein we described in a previous study (E. S. Shang, T. A. Summers, and D. A. Haake, Infect. Immun. 64:2322-2330, 1996). The deduced amino acid sequence of LipL36 would constitute a 364-amino-acid polypeptide with a 20-amino-acid signal peptide, followed by an L-X-Y-C lipoprotein signal peptidase cleavage site. LipL36 is solubilized by Triton X-114 extraction of L. kirschneri; phase separation results in partitioning of LipL36 exclusively into the hydrophobic, detergent phase. LipL36 is intrinsically labeled during incubation of L. kirschneri in media containing [3H]palmitate. Processing of LipL36 is inhibited by globomycin, a selective inhibitor of lipoprotein signal peptidase. After processing, LipL36 is exported to the outer membrane along with LipL41 and lipopolysaccharide. Unlike LipL41, there appears to be differential expression of LipL36. In early-log-phase cultures, LipL36 is one of the most abundant L. kirschneri proteins. However, LipL36 levels drop considerably beginning in mid-log phase. LipL36 expression in vivo was evaluated by examining the humoral immune response to leptospiral antigens in the hamster model of leptospirosis. Hamsters surviving challenge with culture-adapted virulent L. kirschneri generate a strong antibody response to LipL36. In contrast, sera from hamsters surviving challenge with host-adapted L. kirschneri do not recognize LipL36. These findings suggest that LipL36 expression is downregulated during mammalian infection, providing a marker for studying the mechanisms by which pathogenic Leptospira species adapt to the host environment.
- Published
- 1998
- Full Text
- View/download PDF
25. Heat shock response and groEL sequence of Bartonella henselae and Bartonella quintana.
- Author
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Haake DA, Summers TA, McCoy AM, and Schwartzman W
- Subjects
- Amino Acid Sequence, Base Sequence, Chaperonin 60 classification, Chaperonin 60 immunology, Genes, Bacterial, Genetic Code, Molecular Sequence Data, Phylogeny, Polymerase Chain Reaction, Precipitin Tests, Sequence Analysis, DNA, Sequence Homology, Amino Acid, Sequence Homology, Nucleic Acid, Species Specificity, Bartonella henselae physiology, Bartonella quintana physiology, Chaperonin 60 genetics, Heat-Shock Response
- Abstract
Transmission of Bartonella species from ectoparasites to the mammalian host involves adaptation to thermal and other forms of stress. In order to better understand this process, the heat shock response of Bartonella henselae and Bartonella quintana was studied. Cellular proteins synthesized after shift to higher temperatures were intrinsically labelled with [25S]methionine and analysed by gel electrophoresis and fluorography. The apparent molecular masses of three of the major heat shock proteins produced by the two Bartonella species were virtually identical, migrating at 70, 60 and 10 kDa. A fourth major heat shock protein was larger in B. quintana (20 kDa) than in B. henselae (17 kDa). The maximum heat shock response in B. quintana and B. henselae was observed at 39 degrees C and 42 degrees C, respectively. The groEL genes of both Bartonella species were amplified, sequenced and compared to other known groEL genes. The phylogenetic tree based on the groEL alignment places B. quintana and B. henselae in a monophyletic group with Bartonella bacilliformis. The deduced amino acid sequences of Bartonella GroEL homologues contain signature sequences that are uniquely shared by members of the Gram-negative alpha-purple subdivision of bacteria, which live within eukaryotic cells. Recombinant His6-GroEL fusion proteins were expressed in Escherichia coli to generate specific rabbit antisera. The GroEL antisera were used to confirm the identity of the 60 kDa Bartonella heat shock protein. These studies provide a foundation for evaluating the role of the heat shock response in the pathogenesis of Bartonella infection.
- Published
- 1997
- Full Text
- View/download PDF
26. Molecular cloning and sequence analysis of the gene encoding LipL41, a surface-exposed lipoprotein of pathogenic Leptospira species.
- Author
-
Shang ES, Summers TA, and Haake DA
- Subjects
- Amino Acid Sequence, Animals, Anti-Bacterial Agents pharmacology, Base Sequence, Cloning, Molecular, Leptospira genetics, Male, Molecular Sequence Data, Oligonucleotide Probes, Rabbits, Bacterial Proteins genetics, Leptospira chemistry, Lipoproteins genetics, Membrane Proteins genetics, Peptides
- Abstract
We report the cloning of the gene encoding a surface-exposed leptospiral lipoprotein, designated LipL41. In a previous study, a 41-kDa protein antigen was identified on the surface of Leptospira kirschneri (D. A. Haake, E. M. Walker, D. R. Blanco, C. A. Bolin, J. N. Miller, and M. A. Lovett, Infect. Immun. 59:1131-1140, 1991). We obtained the N-terminal amino acid sequence of a staphylococcal V8 proteolytic-digest fragment in order to design an oligonucleotide probe.A Lambda ZAP II library containing EcoRI fragments of L. kirschneri DNA was screened, and a 2.3-kb DNA fragment which contained the entire structural lipL41 gene was identified. The deduced amino acid sequence of LipL41 would encode a 355-amino-acid polypeptide with a 19-amino-acid signal peptide, followed by an L-X-Y-C lipoprotein signal peptidase cleavage site. A recombinant His6-LipL41 fusion protein was expressed in Escherichia coli in order to generate specific rabbit antiserum. LipL41 is solubilized by Triton X-114 extraction of L. kirschneri; phase separation results in partitioning of LipL41 exclusively into the detergent phase. At least eight proteins, including LipL41 and the other major Triton X-114 detergent phase proteins, are intrinsically labeled during incubation of L. kirschneri in media containing [3H] palmitate. Processing of LipL41 is inhibited by globomycin, a selective inhibitor of lipoprotein signal peptidase. Triton X-100 extracts of L. kirschneri contain immunoprecipitable OmpL1 (porin), LipL41, and another lipoprotein, LipL36. However, in contrast to LipL36, only LipL41 and OmpL1 were exposed on the surface of intact organisms. Immunoblot analysis of a panel of Leptospira species reveals that LipL41 expression is highly conserved among leptospiral pathogens.
- Published
- 1996
- Full Text
- View/download PDF
27. The rare outer membrane protein, OmpL1, of pathogenic Leptospira species is a heat-modifiable porin.
- Author
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Shang ES, Exner MM, Summers TA, Martinich C, Champion CI, Hancock RE, and Haake DA
- Subjects
- Base Sequence, Cloning, Molecular, DNA Primers chemistry, Electric Conductivity, Hot Temperature, Lipid Bilayers, Molecular Sequence Data, Molecular Weight, Recombinant Proteins, Bacterial Outer Membrane Proteins physiology, Genes, Bacterial, Leptospira genetics, Porins genetics
- Abstract
The outer membranes of invasive spirochetes contain unusually small amounts of transmembrane proteins. Pathogenic Leptospira species produce a rare 31-kDa surface protein, OmpL1, which has a deduced amino acid sequence predictive of multiple transmembrane beta-strands. Studies were conducted to characterize the structure and function of this protein. Alkali, high-salt, and urea fractionation of leptospiral membranes demonstrated that OmpL1 is an integral membrane protein. The electrophoretic mobility of monomeric OmpL1 was modifiable by heat and reduction; complete denaturation of OmpL1 required prolonged boiling in sodium dodecyl sulfate (SDS), 8 M urea, and 2-mercaptoethanol. When solubilized in SDS at low temperature, a small proportion of OmpL1 exhibited an apparent molecular mass of approximately 90 kDa, indicating the existence of an SDS-unstable oligomer. OmpL1 dimers and trimers were demonstrated by nearest neighbor chemical cross-linking. In order to generate purified protein for functional studies, the ompL1 gene was ligated into the pMMB66 expression plasmid under control of the tac promoter. Although expression in Escherichia coli was toxic, most of the OmpL1 produced was found in the outer membrane, as determined by subcellular fractionation. Purified recombinant OmpL1 was reconstituted into planar lipid bilayers, demonstrating an average single channel conductance of 1.1 nS, similar to the major porin activity of native leptospiral membranes. These findings indicate that OmpL1 spans the leptospiral outer membrane and functions as a porin.
- Published
- 1995
- Full Text
- View/download PDF
28. Worsening right flank pain over a 24-hr period.
- Author
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Summers TA, Fultz PJ, and Sacks D
- Subjects
- Adult, Angiomyolipoma complications, Angiomyolipoma pathology, Female, Hemorrhage diagnostic imaging, Hemorrhage etiology, Hemorrhage pathology, Humans, Kidney diagnostic imaging, Kidney pathology, Kidney Neoplasms complications, Kidney Neoplasms pathology, Pain etiology, Pain pathology, Tomography, X-Ray Computed, Angiomyolipoma diagnostic imaging, Kidney Neoplasms diagnostic imaging, Pain diagnostic imaging
- Abstract
AML is a benign renal tumor composed of variable quantities of mature vascular, smooth muscle and fatty elements. They occur as an isolated finding, classically in middle-aged females, or in association with tuberous sclerosis. When symptomatic, they typically present with flank pain secondary to hemorrhage. CT is the diagnostic imaging modality of choice. The diagnosis can usually be made based on the recognition of fat within the lesion. When discovered, asymptomatic lesions are generally monitored by follow-up imaging studies, and if they remain stable, no intervention is required. Arterial embolization has become the recommended treatment of choice in some instances, particularly in cases with associated hemorrhage.
- Published
- 1994
- Full Text
- View/download PDF
29. The value of duplex sonography after peripheral artery angioplasty in predicting subacute restenosis.
- Author
-
Sacks D, Robinson ML, Summers TA, and Marinelli DL
- Subjects
- Arterial Occlusive Diseases physiopathology, Blood Flow Velocity, Humans, Life Tables, Prospective Studies, Radiography, Recurrence, Ultrasonography, Vascular Patency, Angioplasty, Balloon, Arterial Occlusive Diseases diagnostic imaging, Arterial Occlusive Diseases therapy, Femoral Artery diagnostic imaging, Femoral Artery physiopathology, Popliteal Artery diagnostic imaging, Popliteal Artery physiopathology
- Abstract
Objective: The purpose of this study was to determine if abnormal findings on duplex sonographic examination after peripheral artery angioplasty correlate with the subsequent recurrence of a stenosis., Subjects and Methods: We used duplex sonography to examine 35 stenoses in 23 patients within 48 hr after the patients had angioplasty to treat these stenoses. Patients were followed up for 3 years by using one or more of the following: assessment of signs and symptoms, monitoring of peripheral pulses, pulse volume recordings, and angiography. Life tables were constructed to compare long-term patency with the presence of abnormal findings seen on duplex sonograms. Abnormal findings at the dilated segment included a blood-flow velocity greater than 120 cm/sec or a residual elevated velocity ratio greater than 1.4 or 2.0 immediately after angioplasty., Results: Twelve (34%) of 35 angioplasty sites showed recurrent stenosis before 36 months. Patency at 24 months was calculated for velocities less than 120 cm/sec vs velocities of 120 cm/sec or greater (41% vs 68%), for velocity ratios less than 1.4 vs ratios of 1.4 or greater (63% vs 57%), and for velocity ratios less than 2.0 vs ratios of 2.0 or greater (54% vs 74%). We found no significant difference in patency between those patients with normal findings and those with abnormal findings on duplex sonographic examination after angioplasty., Conclusion: Abnormal findings on duplex sonograms obtained immediately after peripheral angioplasty cannot be used to predict subacute restenosis.
- Published
- 1994
- Full Text
- View/download PDF
30. Matrix mineralization in hypertrophic chondrocyte cultures. Beta glycerophosphate increases type X collagen messenger RNA and the specific activity of pp60c-src kinase.
- Author
-
Coe MR, Summers TA, Parsons SJ, Boskey AL, and Balian G
- Subjects
- Animals, Blotting, Northern, Blotting, Western, Bone Matrix metabolism, Cartilage cytology, Cells, Cultured, Chick Embryo, Collagen genetics, Durapatite, Electrophoresis, Polyacrylamide Gel, Hydroxyapatites metabolism, Phosphorylation, RNA, Messenger genetics, RNA, Messenger metabolism, Calcification, Physiologic, Cartilage metabolism, Collagen biosynthesis, Glycerophosphates pharmacology, Proto-Oncogene Proteins pp60(c-src) metabolism
- Abstract
The phenomenon of chondrocyte hypertrophy is accompanied by the expression of type X collagen and the appearance of matrix mineralization. These events are also associated with changes in the phosphorylation of intracellular proteins. In this study the addition of 10 mM beta-glycerophosphate to hypertrophic chondrocytes resulted in stimulation of type X collagen synthesis up to 10 days in culture and an increase in the expression of type X collagen mRNA. This was followed by the onset of mineralization and the appearance of calcium hydroxyapatite. In contrast, the addition of beta-glycerophosphate to non-hypertrophic chondrocytes failed to induce expression of type X collagen or to produce changes in calcium and phosphate. The increased formation of type X collagen and of mineral in hypertrophic chondrocytes was accompanied by changes in the tyrosine kinase pp60c-src. While the level of c-src protein decreased approximately 2.5-fold in hypertrophic chondrocytes after 17 days of beta-glycerophosphate treatment, the specific activity of pp60c-src kinase increased approximately 3-fold in the cells that could be induced to mineralize but remained unchanged in cells that did not exhibit this property. Regulation of kinase activity may be an important event in endochondral ossification.
- Published
- 1992
- Full Text
- View/download PDF
31. Antegrade selective catheterization of femoral vessels with a 4- or 5-F catheter and safety wire.
- Author
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Sacks D and Summers TA
- Subjects
- Angiography instrumentation, Catheterization methods, Graft Occlusion, Vascular diagnostic imaging, Humans, Obesity complications, Angiography methods, Blood Vessel Prosthesis, Catheterization instrumentation, Femoral Artery
- Abstract
A method of antegrade catheterization of the superficial femoral artery or femoral bypass grafts with a 4- or 5-F catheter and safety wire is described. This method has advantages of smaller size and the use of torque wires when compared with previously described methods.
- Published
- 1991
- Full Text
- View/download PDF
32. Dynamics of a human seminal vesicle specific protein.
- Author
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Flickinger CJ, Herr JC, McGee RS, Sigman M, Evans RJ, Sutherland WM, Summers TA, Spell DR, and Conklin DJ
- Subjects
- Antigens analysis, Antigens metabolism, Antigens, Neoplasm metabolism, Humans, Male, Prostate-Specific Antigen, Proteins analysis, Proteins immunology, Semen chemistry, Seminal Plasma Proteins, Seminal Vesicles ultrastructure, Spermatozoa chemistry, Prostatic Secretory Proteins, Proteins metabolism, Seminal Vesicles metabolism
- Abstract
The present paper is concerned with the temporal alterations and tissue localization of a seminal antigen secreted by the human seminal vesicle. This antigen is recognized by antibody MHS-5, which is one of a set produced in mice by immunization with human sperm. The respective clone produced an antibody of the IgG1 subtype, which reacted with seminal fluid from over 400 normal donors and 21 semen samples from vasectomized men. Incubation of seminal vesicle secretion with either prostatic fluid or prostate specific antigen (PSA) resulted in degradation on the antigen. The experiments showed that MHS-5 antigen is a substrate for the serine protease PSA: Immunohistochemical studies suggested that MHS-5 is a "sperm-coating" antigen and is exclusively synthesized and secreted by the seminal vesicle.
- Published
- 1990
33. Phosphorylation of a chromaffin granule-binding protein by protein kinase C.
- Author
-
Summers TA and Creutz CE
- Subjects
- Adenosine Triphosphate metabolism, Adrenal Medulla enzymology, Animals, Annexins, Calcium pharmacology, Diglycerides pharmacology, Phosphatidylserines pharmacology, Phosphorylation, Protein Kinase C, Serine metabolism, Tetradecanoylphorbol Acetate pharmacology, Threonine metabolism, Carrier Proteins metabolism, Chromaffin Granules enzymology, Chromaffin System enzymology, Membrane Proteins metabolism, Protein Kinases metabolism
- Abstract
Protein kinase C was detected in a group of Ca2+-dependent chromaffin granule membrane-binding proteins (chromobindins) on the basis of Ca2+-, phosphatidylserine-, 1,2-diolein-, and phorbol myristate acetate-stimulated histone kinase activity. When the chromobindins were incubated with [gamma-32P]ATP, Ca2+, and phosphatidylserine, 32P was incorporated predominantly into a protein of mass 37 +/- 1 kilodaltons (chromobindin 9, or CB9). Phosphorylation of this protein was also stimulated by diolein and phorbol myristate acetate, indicating that it is a substrate for the protein kinase C activity present in the chromobindins. Maximum phosphate incorporation into CB9 in the presence of 1 mM Ca2+, 75 micrograms/ml of phosphatidylserine, 2.5 micrograms/ml of diolein, and 12.5 micrograms/ml of dithiothreitol was 0.53 mol/mol of CB9 in 5 min. Eight 32P-labeled phosphopeptides were resolved in two-dimensional electrophoretic maps of trypsin digests of CB9. Phosphoamino acid analysis revealed that phosphorylation was exclusively on serine (94%) and threonine (6%) residues. Incubation of the chromobindins with chromaffin granule membranes in the presence of [gamma-32P]ATP resulted in the incorporation of 32P into eight additional proteins besides CB9 that could be separated from the membranes by centrifugation in the presence of ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. We suggest that phosphorylation of CB9 or these additional eight proteins may regulate events underlying exocytosis in the chromaffin cell.
- Published
- 1985
34. Monoclonal antibodies to type X collagen. Biosynthetic studies using an antibody to the amino-terminal domain.
- Author
-
Summers TA, Irwin MH, Mayne R, and Balian G
- Subjects
- Amino Acid Sequence, Animals, Antigen-Antibody Complex analysis, Cells, Cultured, Chick Embryo, Collagen analysis, Collagen immunology, Enzyme-Linked Immunosorbent Assay, Female, Kinetics, Mice, Mice, Inbred Strains, Microbial Collagenase, Molecular Sequence Data, Organ Culture Techniques, Pepsin A, Antibodies, Monoclonal, Cartilage metabolism, Collagen biosynthesis
- Abstract
Monoclonal antibodies to chick type X collagen have been used to study the structure, biosynthesis, and location of type X in cartilage. The antibodies were produced by injecting purified type X collagen into female SJL/J mice and then fusing their spleen cells with Sp2/0 myeloma cells. Hybridoma culture supernatants were screened for antibodies to type X collagen by enzyme-linked immunosorbent assay and Western blots. Positive supernatants did not cross-react with other collagen types (I, II, IX, XI) or with fibronectin. Three monoclonal antibodies were chosen for further characterization. Two of them (1A6 and 6F6) recognize a pepsin-sensitive domain of type X collagen. Rotary shadowing showed that 1A6 and 6F6 both recognize the same end of type X, probably the aminoterminal non-triple helical domain. Amino acid sequencing of the intact protein and of the epitope-containing peptide confirmed that the antibody recognition sites for 1A6 and 6F6 are within the amino-terminal domain. Monoclonal antibody 2B3 reacts with the pepsinized (45 kDa) and weakly with the nonpepsinized (59 kDa) forms of type X collagen. The monoclonal antibodies were used for immunolocalization of type X in hypertrophic chondrocytes and reacted only with tissue samples from areas undergoing endochondral ossification, e.g. growth plate and fracture callus. Antibody 6F6, when coupled to Sepharose, selectively binds to type X collagen from cell and organ cultures. In a pulse-chase experiment, no processing of the 59-kDa form of type X could be detected. Two components with molecular masses of approximately 70 and 85 kDa, arising from a disulfide-bonded aggregate, were synthesized by both the permanent and calcifying cartilage organ cultures but did not react with the antibody, suggesting that these proteins are not related to type X. In summary, the pulse-chase results and the immune precipitation with monoclonal antibody 6F6 did not detect biosynthetic precursors larger than 59 kDa or proteolytically processed forms of type X.
- Published
- 1988
35. Characterization of a monoclonal antibody to a conserved epitope on human seminal vesicle-specific peptides: a novel probe/marker system for semen identification.
- Author
-
Herr JC, Summers TA, McGee RS, Sutherland WM, Sigman M, and Evans RJ
- Subjects
- Enzyme-Linked Immunosorbent Assay, Fluorescent Antibody Technique, Forensic Medicine, Humans, Male, Methods, Vasectomy, Antibodies, Monoclonal, Epitopes immunology, Peptides immunology, Semen analysis, Seminal Vesicles metabolism
- Abstract
A novel sperm-coating antigen from the human seminal vesicles was discovered. We identified a monoclonal antibody MHS-5, recognizing an epitope with characteristics of a forensic semen marker: conservation in all vasectomized or normal semen samples tested (421); absence in all human tissues or biological fluids other than semen; and immunolocalization on the surface of ejaculated sperm. Western blots of ejaculates allowed to liquefy for 5 min demonstrated the MHS-5 epitope to be located on peptides of a wide range of molecular masses from 69 to 8 kDa. After 15 h of semen liquefaction, immunoreaction peptides of higher molecular mass were undetectable in semen, while peptides of lower molecular mass from 8 to 21 kDa retained antigenicity. Three peptides of 10, 11.9, and 13.7 kDa were the most immunoreactive species in semen liquified for 15 h. Using the MHS-5 monoclonal, an enzyme-linked immunosorbent assay (ELISA) was developed sensitive to 1 ng of seminal protein. This assay showed that the MHS-5 antigen was undetectable in semen of common domestic animals and monkeys but was present in chimpanzee, gorilla, and orangutan semen. ELISA of homogenates from human organs and reproductive tissues demonstrated the antigen only in samples of seminal vesicles. Epididymal sperm obtained at vasovasostomy lacked the MHS-5 epitope, a fact that, together with immunolocalization on ejaculated sperm, demonstrated that the MHS-5 antigen functions as a "sperm-coating antigen." The MHS-5 monoclonal detected semen in sexual-assault evidence obtained six months previously and in mixtures of semen with vaginal or cervical fluid. Assay systems employing the MHS-5 monoclonal may be useful for identification of semen in sexual-assault casework. The MHS-5 epitope resides on novel seminal vesicle-specific peptides whose functions, aside from sperm coating, are uncharacterized.
- Published
- 1986
- Full Text
- View/download PDF
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