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1.
Front Cardiovasc Med ; 11: 1358472, 2024.
Article in English | MEDLINE | ID: mdl-38410244

ABSTRACT

Introduction: Investigating coronary microvascular perfusion responses after myocardial infarction (MI) would aid in the development of flow preserving therapies. Laser speckle contrast imaging (LSCI) is a powerful tool used for real-time, non-contact, full-field imaging of blood flow in various tissues/organs. However, its use in the beating heart has been limited due to motion artifacts. Methods: In this paper, we report the novel use of LSCI, combined with custom speckle analysis software (SpAn), to visualise and quantitate changes in ventricular perfusion in adult and aged mice undergoing ischaemia-reperfusion (IR) injury. The therapeutic benefit of inhibiting the actions of the pro-inflammatory cytokine interleukin-36 (IL-36) was also investigated using an IL-36 receptor antagonist (IL-36Ra). Results: Imaging from uncovered and covered regions of the left ventricle demonstrated that whilst part of the LSCI flux signal was derived from beating motion, a significant contributor to the flux signal came from ventricular microcirculatory blood flow. We show that a biphasic flux profile corresponding to diastolic and systolic phases of the cardiac cycle can be detected without mathematically processing the total flux data to denoise motion artifacts. Furthermore, perfusion responses to ischaemia and postischaemia were strong, reproducible and could easily be detected without the need to subtract motion-related flux signals. LSCI also identified significantly poorer ventricular perfusion in injured aged mice following IR injury which markedly improved with IL-36Ra. Discussion: We therefore propose that LSCI of the heart is possible despite motion artifacts and may facilitate future investigations into the role of the coronary microcirculation in cardiovascular diseases and development of novel therapies.

2.
Front Immunol ; 14: 1257497, 2023.
Article in English | MEDLINE | ID: mdl-37954606

ABSTRACT

Introduction: Opening occluded coronary arteries in patients with myocardial infarction (MI) damages the delicate coronary microvessels through a process called myocardial ischaemia-reperfusion injury. Although mesenchymal stromal cells (MSCs) have the potential to limit this injury, clinical success remains limited. This may be due to (i) poor MSC homing to the heart (ii) infused MSCs, even if derived from the same site, being a heterogeneous population with varying therapeutic efficacy and (iii) conventional 2D culture of MSCs decreasing their homing and beneficial properties. This study investigated whether 3D culture of two distinctly different bone marrow (BM)-derived MSC sub-populations could improve their homing and coronary vasculoprotective efficacy. Methods: Intravital imaging of the anaesthetised mouse beating heart was used to investigate the trafficking and microvascular protective effects of two clonally-derived BM-derived MSC lines, namely CD317neg MSCs-Y201 and CD317pos MSCs-Y202, cultured using conventional monolayer and 3D hanging drop methods. Results: 3D culture consistently improved the adhesive behaviour of MSCs-Y201 to various substrates in vitro. However, it was their differential ability to reduce neutrophil events within the coronary capillaries and improve ventricular perfusion in vivo that was most remarkable. Moreover, dual therapy combined with heparin further improved the vasculoprotection afforded by 3D cultured MSCs-Y201 by also modifying platelet as well as neutrophil recruitment, which subsequently led to the greatest salvage of viable myocardium. Therapeutic benefit could mechanistically be explained by reductions in coronary endothelial oxidative stress and intercellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1 (VCAM-1) expression. However, since this was noted by both 2D and 3D cultured MSCs-Y201, therapeutic benefit is likely explained by the fact that 3D cultured MSCs-Y201 were the most potent sub-population at reducing serum levels of several pro-inflammatory cytokines. Conclusion: This novel study highlights the importance of not only 3D culture, but also of a specific CD317neg MSC sub-population, as being critical to realising their full coronary vasculoprotective potential in the injured heart. Since the smallest coronary blood vessels are increasingly recognised as a primary target of reperfusion injury, therapeutic interventions must be able to protect these delicate structures from inflammatory cells and maintain perfusion in the heart. We propose that relatively feasible technical modifications in a specific BM-derived MSC sub-population could achieve this.


Subject(s)
Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Myocardial Reperfusion Injury , Mice , Animals , Humans , Heparin/pharmacology , Heparin/metabolism , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/metabolism , Myocardial Reperfusion Injury/therapy , Myocardial Reperfusion Injury/metabolism , Microvessels
3.
Cardiovasc Res ; 115(13): 1918-1932, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31062860

ABSTRACT

AIMS: Adequate microcirculatory perfusion, and not just opening of occluded arteries, is critical to salvage heart tissue following myocardial infarction. However, the degree of microvascular perfusion taking place is not known, limited primarily by an inability to directly image coronary microcirculation in a beating heart in vivo. Haematopoietic stem/progenitor cells (HSPCs) offer a potential therapy but little is known about their homing dynamics at a cellular level and whether they protect coronary microvessels. This study used intravital microscopy to image the anaesthetized mouse beating heart microcirculation following stabilization. METHODS AND RESULTS: A 3D-printed stabilizer was attached to the ischaemia-reperfusion injured (IRI) beating heart. The kinetics of neutrophil, platelet and HSPC recruitment, as well as functional capillary density (FCD), was imaged post-reperfusion. Laser speckle contrast imaging (LSCI) was used for the first time to monitor ventricular blood flow in beating hearts. Sustained hyperaemic responses were measured throughout reperfusion, initially indicating adequate flow resumption. Intravital microscopy confirmed large vessel perfusion but demonstrated poor transmission of flow to downstream coronary microvessels. Significant neutrophil adhesion and microthrombus formation occurred within capillaries with the latter occluding them, resulting in patchy perfusion and reduced FCD. Interestingly, 'patrolling' neutrophils were also observed in capillaries. Haematopoietic stem/progenitor cells readily trafficked through the heart but local retention was poor. Despite this, remarkable anti-thromboinflammatory effects were observed, consequently improving microvascular perfusion. CONCLUSION: We present a novel approach for imaging multiple microcirculatory perturbations in the beating heart with LSCI assessment of blood flow. Despite deceptive hyperaemic responses, increased microcirculatory flow heterogeneity was seen, with non-perfused areas interspersed with perfused areas. Microthrombi, rather than neutrophils, appeared to be the major causative factor. We further applied this technique to demonstrate local stem cell presence is not a pre-requisite to confer vasculoprotection. This is the first detailed in vivo characterization of coronary microcirculatory responses post-reperfusion injury.


Subject(s)
Cell Tracking , Coronary Thrombosis/surgery , Coronary Vessels/diagnostic imaging , Hematopoietic Stem Cell Transplantation , Intravital Microscopy , Microvessels/diagnostic imaging , Myocardial Infarction/surgery , Myocardial Reperfusion Injury/surgery , Animals , Cell Line , Coronary Circulation , Coronary Thrombosis/diagnostic imaging , Coronary Thrombosis/pathology , Coronary Thrombosis/physiopathology , Coronary Vessels/pathology , Coronary Vessels/physiopathology , Disease Models, Animal , Hyperemia/diagnostic imaging , Hyperemia/physiopathology , Kinetics , Male , Mice, Inbred C57BL , Microcirculation , Microvessels/pathology , Microvessels/physiopathology , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Myocardial Reperfusion Injury/diagnostic imaging , Myocardial Reperfusion Injury/pathology , Myocardial Reperfusion Injury/physiopathology , Neutrophils/pathology
4.
Stem Cells ; 33(9): 2785-97, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26124062

ABSTRACT

Mesenchymal stem cells (MSCs) have shown therapeutic promise in many experimental and clinical models of inflammation. However, a commonly reported feature of MSC transplantation is poor homing to injured tissues. Previously, we have shown that pretreatment with cytokines/chemical factors enhances hematopoietic SC adhesion within intestinal microvasculature following ischemia-reperfusion (IR) injury. Using intravital microscopy, the ability of similar pretreatment strategies to enhance the recruitment of murine MSCs to murine intestinal microvasculature following IR injury was investigated. Primary MSCs were isolated from bone marrow and selected on the basis of platelet-derived growth factor receptor-α and SC antigen-1 positivity (PDGFRα(+) /Sca-1(+) ). MSC recruitment was similar in IR injured gut mucosa when compared with sham operated controls, with limited cell adhesion observed. MSCs appeared contorted in microvessels, suggesting physical entrapment. Although not recruited specifically by injury, MSC administration significantly reduced neutrophil recruitment and improved tissue perfusion in the severely injured jejunum. Vasculoprotective effects were not demonstrated in the lesser injured ileum. Pretreatment of MSCs with tumor necrosis factor (TNF)-α, CXCL12, interferon (IFN)-γ, or hydrogen peroxide did not enhance their intestinal recruitment. In fact, TNFα and IFNγ removed the previous therapeutic ability of transplanted MSCs to reduce neutrophil infiltration and improve perfusion in the jejunum. We provide direct evidence that MSCs can rapidly limit leukocyte recruitment and improve tissue perfusion following intestinal IR injury. However, this study also highlights complexities associated with strategies to improve MSC therapeutic efficacy. Future studies using cytokine/chemical pretreatments to enhance MSC recruitment/function require careful consideration and validation to ensure therapeutic function is not impeded.


Subject(s)
Cell Movement/physiology , Ileum/blood supply , Ileum/injuries , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/physiology , Reperfusion Injury/prevention & control , Animals , Cell Movement/drug effects , Cytokines/metabolism , Cytokines/pharmacology , Ileum/metabolism , Male , Mesenchymal Stem Cells/drug effects , Mice , Mice, Inbred C57BL , Reperfusion Injury/metabolism
5.
Stem Cell Rev Rep ; 10(4): 587-99, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24752328

ABSTRACT

There is significant interest in the use of mesenchymal stem cells (MSCs) as a potential therapeutic modality in disease and disorder, particularly those with an inflammation-based component such as coronary, renal and hepatic diseases. While there is no question that MSCs possess the capability to manipulate an ongoing inflammatory injury, the recruitment of these cells to injured sites is generally poor, and thus, open to manipulation. Enhancing the localised recruitment of MSCs to injured tissues may enhance the efficiency and efficacy of this mode of therapy. A number of techniques exist in the literature to improve the recruitment of MSCs to injured tissues, including the use of cytokines, chemical modifications and coating with either synthetic or biological particles. In addition to enhancing MSC recruitment, there is an increasing body of work examining techniques which may enhance the anti-inflammatory activity of these cells. This review will summarise the literature around these topics. This first section of this review summarises the current literature with regard to MSC homing and their recruitment during conditions of injury. In relation to the anti-inflammatory activity of MSCs, the role of systemic versus local activity will be discussed. The second part of the review focuses on the role of pretreatments in MSC therapy and how these may have potential for not only enhancing the recruitment of MSCs, but also their anti-inflammatory capabilities. In summary, it is clear that there is significant potential to improve the efficiency of MSC therapy and the techniques discussed in this review may be central to this in the future.


Subject(s)
Cell Adhesion/physiology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/physiology , Tissue Engineering , Animals , Humans
6.
PLoS One ; 8(6): e66489, 2013.
Article in English | MEDLINE | ID: mdl-23840488

ABSTRACT

INTRODUCTION: Renal disease affects over 500 million people worldwide and is set to increase as treatment options are predominately supportive. Evidence suggests that exogenous haematopoietic stem cells (HSCs) can be of benefit but due to the rarity and poor homing of these cells, benefits are either minor or transitory. Mechanisms governing HSC recruitment to injured renal microcirculation are poorly understood; therefore this study determined (i) the adhesion molecules responsible for HSC recruitment to the injured kidney, (ii) if cytokine HSC pre-treatment can enhance their homing and (iii) the molecular mechanisms accountable for any enhancement. METHODS: Adherent and free-flowing HSCs were determined in an intravital murine model of renal ischaemia-reperfusion injury. Some HSCs and animals were pre-treated prior to HSC infusion with function blocking antibodies, hyaluronidase or cytokines. Changes in surface expression and clustering of HSC adhesion molecules were determined using flow cytometry and confocal microscopy. HSC adhesion to endothelial counter-ligands (VCAM-1, hyaluronan) was determined using static adhesion assays in vitro. RESULTS: CD49d, CD44, VCAM-1 and hyaluronan governed HSC adhesion to the IR-injured kidney. Both KC and SDF-1α pre-treatment strategies significantly increased HSC adhesion within injured kidney, whilst SDF-1α also increased numbers continuing to circulate. SDF-1α and KC did not increase CD49d or CD44 expression but increased HSC adhesion to VCAM-1 and hyaluronan respectively. SDF-1α increased CD49d surface clustering, as well as HSC deformability. CONCLUSION: Increasing HSC adhesive capacity for its endothelial counter-ligands, potentially through surface clustering, may explain their enhanced renal retention in vivo. Furthermore, increasing HSC deformability through SDF-1α treatment could explain the prolonged systemic circulation; the HSC can therefore continue to survey the damaged tissue instead of becoming entrapped within non-injured sites. Therefore manipulating these mechanisms of HSC recruitment outlined may improve the clinical outcome of cellular therapies for kidney disease.


Subject(s)
Cell Adhesion , Chemokines/physiology , Hematopoietic Stem Cells/pathology , Kidney/blood supply , Reperfusion Injury/pathology , Animals , Chemokine CXCL12/administration & dosage , Kidney/pathology , Mice , Reperfusion Injury/metabolism
7.
PLoS One ; 8(3): e59150, 2013.
Article in English | MEDLINE | ID: mdl-23554986

ABSTRACT

OBJECTIVES: Although haematopoietic stem cells (HSCs) migrate to injured gut, therapeutic success clinically remains poor. This has been partially attributed to limited local HSC recruitment following systemic injection. Identifying site specific adhesive mechanisms underpinning HSC-endothelial interactions may provide important information on how to enhance their recruitment and thus potentially improve therapeutic efficacy. This study determined (i) the integrins and inflammatory cyto/chemokines governing HSC adhesion to injured gut and muscle (ii) whether pre-treating HSCs with these cyto/chemokines enhanced their adhesion and (iii) whether the degree of HSC adhesion influenced their ability to modulate leukocyte recruitment. METHODS: Adhesion of HPC-7, a murine HSC line, to ischaemia-reperfused (IR) injured mouse gut or cremaster muscle was monitored intravitally. Critical adhesion molecules were identified by pre-treating HPC-7 with blocking antibodies to CD18 and CD49d. To identify cyto/chemokines capable of recruiting HPC-7, adhesion was monitored following tissue exposure to TNF-α, IL-1ß or CXCL12. The effects of pre-treating HPC-7 with these cyto/chemokines on surface integrin expression/clustering, adhesion to ICAM-1/VCAM-1 and recruitment in vivo was also investigated. Endogenous leukocyte adhesion following HPC-7 injection was again determined intravitally. RESULTS: IR injury increased HPC-7 adhesion in vivo, with intestinal adhesion dependent upon CD18 and muscle adhesion predominantly relying on CD49d. Only CXCL12 pre-treatment enhanced HPC-7 adhesion within injured gut, likely by increasing CD18 binding to ICAM-1 and/or CD18 surface clustering on HPC-7. Leukocyte adhesion was reduced at 4 hours post-reperfusion, but only when local HPC-7 adhesion was enhanced using CXCL12. CONCLUSION: This data provides evidence that site-specific molecular mechanisms govern HPC-7 adhesion to injured tissue. Importantly, we show that HPC-7 adhesion is a modulatable event in IR injury and further demonstrate that adhesion instigated by injury alone is not sufficient for mediating anti-inflammatory effects. Enhancing local HSC presence may therefore be essential to realising their clinical potential.


Subject(s)
Endothelium, Vascular/pathology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Intestines/blood supply , Reperfusion Injury/pathology , Animals , Antigens, CD/genetics , Antigens, CD/immunology , Cell Adhesion/immunology , Cell Line , Chemokine CXCL12/pharmacology , Chemotaxis/drug effects , Chemotaxis/immunology , Endothelium, Vascular/immunology , Gene Expression , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/immunology , Integrins/genetics , Integrins/immunology , Intercellular Adhesion Molecule-1/genetics , Intercellular Adhesion Molecule-1/immunology , Interleukin-1beta/pharmacology , Intestines/immunology , Intestines/injuries , Male , Mice , Mice, Inbred C57BL , Microcirculation , Reperfusion Injury/immunology , Tumor Necrosis Factor-alpha/pharmacology , Vascular Cell Adhesion Molecule-1/genetics , Vascular Cell Adhesion Molecule-1/immunology
8.
Cell Transplant ; 22(8): 1485-99, 2013.
Article in English | MEDLINE | ID: mdl-22889470

ABSTRACT

Hematopoietic stem cells (HSCs) migrate to injury sites and aid in tissue repair. However, clinical success is poor and is partially due to limited HSC recruitment. We hypothesized that HSC pretreatment with H2O2 would enhance their recruitment to injured gut. As HSCs are rare cells, the number of primary cells obtained from donors is often inadequate for functional experiments. To circumvent this, in this study we utilized a functionally relevant cell line, HPC-7. Anesthetized mice were subjected to intestinal ischemia-reperfusion (IR) injury, and HPC-7 recruitment was examined intravitally. Adhesion to endothelial cells (ECs), injured gut sections, and ICAM-1/VCAM-1 protein were also quantitated in vitro. H2O2 pretreatment significantly enhanced HPC-7 recruitment to injured gut in vivo. A concomitant reduction in pulmonary adhesion was also observed. Enhanced adhesion was also observed in all in vitro models. Increased clustering of α4 and ß2 integrins, F-actin polymerization, and filopodia formation were observed in pretreated HPC-7s. Importantly, H2O2 did not reduce HPC-7 viability or proliferative ability. HPC-7 recruitment to injured gut can be modulated by H2O2 pretreatment. This may be through increasing the affinity or avidity of surface integrins that mediate HPC-7 homing to injured sites or through stimulating the migratory apparatus. Strategies that enhance hematopoietic stem/progenitor cell recruitment may ultimately affect their therapeutic efficacy.


Subject(s)
CD18 Antigens/metabolism , Gastrointestinal Tract/pathology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Hydrogen Peroxide/pharmacology , 8-Hydroxy-2'-Deoxyguanosine , Animals , Apoptosis/drug effects , Cell Adhesion/drug effects , Cell Line , Cellular Senescence/drug effects , Culture Media, Conditioned/pharmacology , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/metabolism , Endothelium/drug effects , Endothelium/metabolism , Frozen Sections , Gastrointestinal Tract/drug effects , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/ultrastructure , Lung/drug effects , Lung/pathology , Male , Mice , Mice, Inbred C57BL , Reperfusion Injury/pathology , Reperfusion Injury/therapy
9.
Endoscopy ; 42(10): 781-9, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20857372

ABSTRACT

BACKGROUND AND STUDY AIMS: The AIM-II Trial included patients with nondysplastic Barrett's esophagus (NDBE) treated with radiofrequency ablation (RFA). Complete eradication of NDBE (complete response-intestinal metaplasia [CR-IM]) was achieved in 98.4 % of patients at 2.5 years. We report the proportion of patients demonstrating CR-IM at 5-year follow-up. PATIENTS AND METHODS: Prospective, multicenter US trial (NCT00489268). After endoscopic RFA of NDBE up to 6 cm, patients with CR-IM at 2.5 years were eligible for longer-term follow-up. At 5 years, we obtained four-quadrant biopsies from every 1 cm of the original extent of Barrett's esophagus. All specimens were reviewed by one expert gastrointestinal pathologist, followed by focal RFA and repeat biopsy if NDBE was identified. Primary outcomes were (i) proportion of patients demonstrating CR-IM at 5-year biopsy, and (ii) proportion of patients demonstrating CR-IM at 5-year biopsy or after the single-session focal RFA. RESULTS: Of 60 eligible patients, 50 consented to participate. Of 1473 esophageal specimens obtained at 5 years 85 % contained lamina propria or deeper tissue (per patient, mean 30 , standard deviation [SD] 13). CR-IM was demonstrated in 92 % (46 / 50) of patients, while 8 % (4 / 50) had focal NDBE; focal RFA converted all these to CR-IM. There were no buried glands, dysplasia, strictures, or serious adverse events. Kaplan-Meier CR-IM survival analysis showed probability of maintaining CR-IM for at least 4 years after first durable CR-IM was 0.91 (95 % confidence interval [CI] 0.77 - 0.97) and mean duration of CR-IM was 4.22 years (standard error [SE] 0.12). CONCLUSIONS: In patients with NDBE treated with RFA, CR-IM was demonstrated in the majority of patients (92 %) at 5-year follow-up, biopsy depth was adequate to detect recurrence, and all failures (4 / 4, 100 %) were converted to CR-IM with single-session focal RFA.


Subject(s)
Barrett Esophagus/pathology , Barrett Esophagus/surgery , Catheter Ablation , Esophagus/pathology , Esophagus/surgery , Metaplasia/surgery , Adult , Aged , Biopsy/methods , Cohort Studies , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Prospective Studies , Recurrence , Reoperation , Salvage Therapy , Statistics, Nonparametric , Treatment Outcome
11.
Am J Surg Pathol ; 25(4): 508-15, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11257626

ABSTRACT

Granulomatous appendicitis is an enigmatic entity. Purported causes include Crohn's disease, foreign body reactions, sarcoidosis, and infectious agents; however, most cases remain idiopathic. Yersinia enterocolitica (YE) and Y. pseudotuberculosis (YP) have been implicated as causes of appendicitis, ileocolitis, and mesenteric adenitis. The authors examined the potential role of YE and YP in granulomatous appendicitis using histologic and molecular methods. Forty cases of granulomatous appendicitis were evaluated for histologic features including transmural inflammation, number and character of granulomas, and mucosal changes. Twort Gram, Grocott methenamine-silver (GMS), and Ziehl-Neelsen stains were evaluated, and polymerase chain reaction (PCR) analysis was performed to identify pathogenic YP and YE. Twenty-five percent (10 of 40) of the cases were positive for pathogenic Yersinia by PCR (four YE, four YP, and two with both species). Prominent histologic features included epithelioid granulomas with lymphoid cuffing, transmural inflammation with lymphoid aggregates, mucosal ulceration, and cryptitis. One Yersinia-positive case contained mural Gram-negative bacilli; fungal and acid-fast bacilli stains were all negative. Except for one culture-negative case, serologies and cultures were not done or results were unavailable. Two Yersinia-positive patients were diagnosed subsequently with Crohn's disease, suggesting a possible relationship between the two entities. No other patients developed significant sequelae. YE and YP are important causes of granulomatous appendicitis, and Yersinia infection may mimic Crohn's disease. No histologic features distinguish reliably between Yersinia species, or between Yersinia-positive and Yersinia-negative cases. Because special stains and cultures are often not diagnostic, PCR analysis is an excellent technique for the diagnosis of Yersinia.


Subject(s)
Appendicitis/pathology , Granuloma/pathology , Yersinia Infections/pathology , Yersinia enterocolitica/pathogenicity , Yersinia pseudotuberculosis/pathogenicity , Adolescent , Adult , Aged , Aged, 80 and over , Appendicitis/microbiology , Appendix/microbiology , Appendix/pathology , Child , DNA, Bacterial/analysis , Female , Granuloma/microbiology , Humans , Male , Middle Aged , Polymerase Chain Reaction , Sensitivity and Specificity , Yersinia enterocolitica/genetics , Yersinia enterocolitica/isolation & purification , Yersinia pseudotuberculosis/genetics , Yersinia pseudotuberculosis/isolation & purification
12.
Blood ; 95(10): 3065-70, 2000 May 15.
Article in English | MEDLINE | ID: mdl-10807770

ABSTRACT

Preliminary reports have suggested that survivors of childhood cancer and aplastic anemia who are infected with the hepatitis C virus (HCV) have a low risk for progression to significant liver disease. Among our surviving patients who were transfused between 1961 and March 1992, 77 (6.6% of surviving patients tested thus far) have evidence of HCV infection, whereas 4 surviving patients who were transfused after March 1992 are HCV-infected. One patient chronically infected with HCV died of liver failure, and 2 patients died of hepatocellular carcinoma. To characterize the risk for these and other complications, 65 patients are enrolled in a longitudinal study of HCV infection, of whom 58 (89.2%) had circulating HCV RNA at the time of protocol enrollment, with genotypes 1A and 1B most commonly isolated. Most enrolled patients have few or no symptoms, carry out normal activities, and have normal liver function. To date, 35 patients have undergone liver biopsy for abnormal liver function since the diagnosis of primary malignancy; central pathology review shows 28 (80%) have chronic active hepatitis, 25 (71%) have fibrosis, and 3 (9%) have cirrhosis. These preliminary data suggest that though most survivors of childhood cancer who are infected with HCV are clinically well, some are at risk for clinically significant liver disease. Identification of other HCV-infected patients and prospective monitoring of this cohort are ongoing to determine the risk for, and to identify factors associated with the progression of, liver disease.


Subject(s)
Anemia, Aplastic/complications , Hepacivirus/isolation & purification , Hepatitis C/etiology , Hepatitis C/physiopathology , Neoplasms/complications , Adult , Anemia, Aplastic/physiopathology , Child , Child, Preschool , Chronic Disease , Humans , Neoplasms/physiopathology , Time Factors
13.
J Clin Forensic Med ; 4(1): 17-9, 1997 Mar.
Article in English | MEDLINE | ID: mdl-15335592
14.
Hum Pathol ; 28(2): 174-8, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9023398

ABSTRACT

Several studies have documented the frequent occurrence of human papillomavirus (HPV) DNA in esophageal squamous cell carcinomas (ESCC) in patients from geographic regions where the incidence of this type of cancer is high, such as parts of China. However, the prevalence of HPV infection in ESCC in patients from low incidence geographic regions, such as North America, remains controversial. Therefore, this study evaluates the prevalence of HPV in ESCC in patients from North America, a region where the population is considered at low risk for the development of this neoplasm. ESCCs in 51 patients from three North American cities were analyzed for the presence of HPV DNA by a highly sensitive and specific polymerase chain reaction (PCR) method. Tumor DNA was extracted from formalin-fixed, paraffin-embedded tissue specimens and assayed by PCR using an L1 HPV consensus sequence primer, as well as HPV 16 and HPV 18 E7 region primers. The use of consensus primers to the L1 region allows for detection of most known HPV types and many novel HPV types. Appropriately sized reaction products were analyzed by restriction fragment length polymorphism (RFLP) to confirm the presence and type of HPV, and to exclude products produced by amplification of human DNA sequences. After complete analysis, only one case (2%) of ESCC was HPV DNA positive. This case was independently confirmed using L1 and E7 consensus primers as HPV type 16 and was the only case that tested positive with either assay. These results show that, in contrast to geographic regions where ESCC is prevalent, HPV infection occurs infrequently in association with ESCC in patients from North America.


Subject(s)
Carcinoma, Squamous Cell/etiology , Esophageal Neoplasms/etiology , Papillomaviridae/isolation & purification , Papillomavirus Infections/epidemiology , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/complications , Carcinoma, Squamous Cell/virology , DNA, Neoplasm/chemistry , DNA, Viral/analysis , Esophageal Neoplasms/complications , Esophageal Neoplasms/virology , Female , Humans , Male , Middle Aged , North America/epidemiology , Papillomavirus Infections/complications , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
16.
Death Stud ; 20(4): 415-24, 1996.
Article in English | MEDLINE | ID: mdl-10160573

ABSTRACT

A preliminary model of the escape theory of suicide was tested in 168 college students (52 males, 116 females), who completed self-report measures of self-oriented, other-oriented, and socially prescribed perfectionism, negative life stress, depression, hopelessness, anxiety, reasons for living, and suicidal behaviors. A path analysis provided only partial validation for the model and accounted for 26% of the variance in suicidal behaviors. None of the three dimensions of perfectionism significantly accounted for any additional variance in suicidal behaviors above and beyond the other variables used in the study. Socially prescribed perfectionism was the only dimension of perfectionism that showed a statistically significant bivariate correlation with suicidal behaviors. The path analysis indicated that this correlation was an indirect effect through reasons for living. Depression was a better predictor of suicidal behaviors than hopelessness. Perhaps one reason for these equivocal results was the limited amount of variability in suicidal behaviors in this nonclinical sample.


Subject(s)
Escape Reaction , Models, Psychological , Self-Assessment , Students/psychology , Suicide/psychology , Adolescent , Adult , Female , Forecasting , Humans , Male , Universities
17.
Am J Surg Pathol ; 20(1): 94-102, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8540614

ABSTRACT

A clinical syndrome of chronic colitis unique to the sigmoid colon harboring diverticular was recently reported; its histopathological appearance has not been fully elucidated. In this study, the authors analyzed the clinical and pathological features of 23 patients (age range, 38-87 years; median age, 72 years) with diverticular disease-associated chronic colitis. Nineteen presented with hematochezia; four had abdominal pain. Colonoscopic visualization of the mucosa showed patchy or confluent granularity and friability affecting the sigmoid colon encompassing diverticular ostia. Colonic mucosae proximal and distal to the sigmoid were endoscopically normal. Mucosal biopsy specimens showed features of idiopathic inflammatory bowel disease that included plasmacellular and eosinophilic expansion of the lamina propria (100%), neutrophilic cryptitis (100%) with crypt abscesses (61%), basal lymphoid aggregates (100%), distorted crypt architecture (87%), basal plasmacytosis (61%), surface epithelial sloughing (61%), focal Paneth cell metaplasia (48%), and granulomatous cryptitis (26%). Concomitant rectal biopsies obtained in five patients demonstrated histologically normal mucosa. Fourteen patients treated with high-fiber diet or antibiotics or both improved clinically, as did nine patients administered sulfasalazine or 5-aminosalicylic acid. Five patients underwent sigmoid colonic resection, three for stricture with obstruction and two for chronic blood loss anemia. Among a control population of 23 age- and gender-matched patients with diverticular disease without luminal surface mucosal abnormality, none required resection during the same follow-up period. By Fisher's exact test, a statistically significant difference in outcome for patients with and without colitis was detected (p = 0.049). In addition, three patients developed ulcerative proctosigmoiditis 6, 9, and 17 months after the onset of diverticular disease-associted colitis. The data indicate that diverticular disease-associated chronic sigmoid colitis expresses morphological features traditionally reserved for idiopathic inflammatory bowel disease. Its clinical and endoscopic profiles permit distinction from Crohn's disease and ulcerative colitis. Patients with chronic colitis in conjunction with diverticula are at increased risk for sigmoid colonic resection. Diverticular disease-associated chronic colitis may also precede the onset of conventional ulcerative proctosigmoiditis in some cases.


Subject(s)
Colitis/etiology , Diverticulum, Colon/complications , Adult , Aged , Aged, 80 and over , Chronic Disease , Colitis/pathology , Colitis/therapy , Colonoscopy , Diagnosis, Differential , Diverticulum, Colon/therapy , Female , Follow-Up Studies , Humans , Inflammatory Bowel Diseases/pathology , Intestinal Mucosa/pathology , Male , Middle Aged
18.
Suicide Life Threat Behav ; 26(2): 181-6, 1996.
Article in English | MEDLINE | ID: mdl-8840422

ABSTRACT

A model of the escape theory of suicide was tested, using the following measures: the Life Experiences Survey, the Socially Prescribed Perfectionism subscale, the Self-Rating Depression Scale, the Hopelessness Scale, the Reasons for Living Inventory, and the Scale for Suicide Ideation. College students (N = 114) completed all of these measures, and results were correlated. LISREL path analysis failed to validate the proposed model. All proposed paths were significant, except for the reciprocal path proposed between negative life events and socially prescribed perfectionism. Two residual paths were also significant: from socially prescribed perfectionism to suicide ideation, and from hopelessness to suicide ideation. A revised model constructed from these significant paths had a good overall fit, which suggests that an interactional model is more appropriate than a linear one.


Subject(s)
Defense Mechanisms , Escape Reaction , Students/psychology , Suicide/psychology , Adolescent , Adult , Depressive Disorder/diagnosis , Depressive Disorder/psychology , Female , Humans , Life Change Events , Male , Personality Inventory , Risk Factors , Social Conformity , Suicide Prevention
19.
Am J Surg Pathol ; 19(4): 454-62, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7694947

ABSTRACT

Ischemic colitis, a condition of middle-aged to elderly patients, occurs uncommonly in younger persons. In this study, we describe the clinical and pathological features of 18 young adults (mean age, 29 years; age range, 17-39 years) with spontaneous ischemic colitis, 17 of whom were women. All presented with abrupt onset of severe, cramping abdominal pain followed by hematochezia. Colonoscopic visualization of the mucosa showed segmental hyperemia, friability, and erosion affecting the distal transverse colon (three cases), splenic flexure (three cases), descending colon (five cases), and sigmoid (seven cases). Mucosal biopsy documented superficial ischemic necrosis in seven patients; 11 patients had full-thickness mucosal necrosis with regeneration. Colonic mucosa proximal and distal to the ischemic segment was endoscopically normal in all patients and histologically normal in the eight patients in whom biopsies were obtained. All patients recovered with supportive care. Median duration of illness was 2.1 days (range, 1-4 days). Ten women (59%) were using low-dose estrogenic oral contraceptive agents, compared with the 1988 national average of 18.5% oral contraceptive users among females aged 15 to 44 years. The calculated odds ratio yielded a greater than sixfold relative risk for the occurrence of ischemic colitis among oral contraceptive users. In addition, four women not currently on hormonal contraceptive therapy had a past history of oral contraceptive use; the three remaining women were taking estrogen as replacement therapy after oophorectomy. In one patient, documented reversible ischemic colitis recurred on resumption of oral contraceptive use; four women reported symptoms and signs of recurrent ischemia but did not seek further medical evaluation. Our data indicate that transient colonic ischemia represents a form of acute segmental colitis in young adults; before the 5th decade of life, spontaneous ischemic colitis is a disorder found almost exclusively in women and is associated with the clinical use of exogenous estrogenic agents.


Subject(s)
Colitis, Ischemic/chemically induced , Contraceptives, Oral/adverse effects , Adolescent , Adult , Biopsy , Colitis, Ischemic/pathology , Colitis, Ischemic/therapy , Female , Follow-Up Studies , Humans , Male , Risk Factors
20.
Hum Pathol ; 26(1): 31-8, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7821914

ABSTRACT

The presence of lymphoid aggregates within the muscularis propria or pericolic fibroadipose tissue apposing invasive colorectal carcinoma, termed the Crohn's-like lymphoid reaction, has been related to improved patient length of survival according to univariate statistical analysis. We tested the Crohn's-like lymphoid reaction as an indicator of prognosis in a multivariate statistical analysis of 344 resected right-sided colonic cancers. Improved 5-year survival in univariate analysis was associated with low tumor grade, regular tubule configuration, expanding tumor growth pattern, prominent peritumoral lymphocytic infiltration, absence of tumoral invasion of extramural veins, all levels of intramural and extramural invasion short of widespread local tumor permeation, conspicuous Crohn's-like lymphoid reaction, and absence of both nodal metastasis and nodal-independent tumor nodules in pericolic fat. By the Cox proportional hazard model using the stepwise method, depth of tumor invasion, lymph node metastasis, Crohn's-like lymphoid reaction, and metastatic tumor nodules in pericolic fat retained independent prognostic significance. Combining the four variables to formulate pathological prognostic categories yielded a highly favorable prognostic group-92% 5-year survival and 95% confidence limits (88% to 96%)--encompassing 53% of the study population. It included all Dukes' stage A carcinomas, 66% of Dukes' stage B adenocarcinomas, and 11% of Dukes' stage C cancers. Lymph node metastases coupled with intramural and extramural extent of tumor invasion are the cornerstones of colorectal cancer staging. Addition of other variables improves prognostication for the cecum and ascending colon. From this study the Crohn's-like lymphoid reaction and metastatic tumor nodules in pericolic fat emerge as significant independent indicators of prognosis for right-sided colon cancer. Complex correlations of both indicators with nonselected variables were observed.


Subject(s)
Adenocarcinoma/pathology , Colon/pathology , Colonic Neoplasms/pathology , Crohn Disease/pathology , Lymphoid Tissue/pathology , Adenocarcinoma/immunology , Adenocarcinoma/secondary , Adipose Tissue/pathology , Cell Aggregation , Colon/immunology , Colonic Neoplasms/immunology , Colonic Neoplasms/mortality , Humans , Multivariate Analysis , Muscle, Smooth/pathology , Neoplasm Staging , Prognosis , Proportional Hazards Models , Survival Analysis
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