Immobilized platelets support human colon carcinoma cell tethering, rolling, and firm adhesion under dynamic flow conditions

Accumulating evidence suggests that successful metastatic spread may depend on the ability of tumor cells to undergo extensive interactions with platelets. However, the mechanisms mediating tumor cell adhesion to platelets under conditions of flow remain largely unknown. Therefore, this study was designed to analyze the ability of 3 human colon carcinoma cell lines (LS174T, COLO205, and HCT-8) to bind to surface-anchored platelets under flow and to identify the receptors involved in these processes. Immobilized platelets support LS174T cell adhesion at wall shear stresses up to 1.4 dyn/cm(2). Our data suggest that platelets primarily recruit LS174T cells through a 2-step, sequential process of adhesive interactions that shares common features but is distinct from that elaborated for neutrophils. Platelet P-selectin mediates LS174T cell tethering and rolling in a PSGL-1- and CD24-independent manner. Moreover, platelet alpha(IIb)beta(3)-integrins appear to be capable of directly capturing LS174T cells from the fluid stream, and also convert instantaneously transient tethers initiated by P-selectin into stable adhesion. This step is at least partially mediated by von Willebrand factor, but not fibrinogen or fibronectin, that bridges platelet alpha(IIb)beta(3) with a yet unidentified receptor on the LS174T cell surface via an RGD-dependent mechanism. The sequential engagement of platelet P-selectin and alpha(IIb)beta(3) is also requisite for the optimal adhesion of COLO205. Furthermore, HCT-8 cells, which fail to interact with P-selectin, tether minimally to surface-anchored platelets under flow, despite their extensive adhesive interactions under static conditions. This cascade of events depicts an efficacious process for colon carcinoma arrest at sites of vascular injury. (Blood. 2000;96:1789-1797)     

Synthesis and antimicrobial evaluation of some new cyclooctanones and cyclooctane-based heterocycles

The versatile synthon (E)-2-((dimethyl amino)methylene)cyclooctanone (2) was used as a key intermediate for the synthesis of cyclooctanones and cyclooctane-based heterocycles with pyrazole, isoxazole, pyrimidine, pyrazolopyrimidine, triazolopyrimidine and imidazopyrimidine derivatives via its reactions with several nitrogen nucleophiles. The newly synthesized compounds were screened in vitro for their antimicrobial activity against pathogenic microorganisms (Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans). Most of the tested compounds showed moderate to high antibacterial and antifungal effects against the tested pathogenic microorganisms. Among the synthesized compounds, 2-((p-sulfonamidophenyl)methylene)cyclooctanone (5) showed excellent activity against Listeria monocytogenes.     

Current and future treatment of pulmonary hypertension

Pulmonary hypertension is a disorder characterized by an increase in mean pulmonary arterial pressure (mPAP > 25 mmHg), which is responsible for the transport of blood from the heart to the lungs. Increased pressure leads to decreased flow of blood through the lungs and decreased oxygen deliverance throughout the body. The disorder causes right ventricular hypertrophy and can quickly lead to death, especially with the severe forms of pulmonary hypertension. Symptoms include fatigue, shortness of breath, dizziness and peripheral edema in the lower extremities. Symptoms are usually delayed in appearance and progress slowly, which leads to a late diagnosis and often a poor prognosis. Despite large advances in the last 10 years, there is still about a 15% annual mortality for diagnosed patients. Despite the number of medications available, there are still no cures for this fatal disease. Current therapies include endothelin receptor antagonists, prostacyclin agonists and cGMP-specific 3',5'-cyclic phosphodiesterase (PDE5) inhibitors or combinations. Recent strategies have shown promise in animal models to prevent the onset of pulmonary hypertension when it is induced. However, few of them show a sustained benefit in clinical trials. Strategies for the cure of this debilitating disease should be the focus of future research.     

Impact of SEN virus on immunoblot INNO-LIA HCV reactivity pattern and disease outcome in Egyptian hepatocellular carcinoma patients

Recently, a novel virus designated SEN virus (SENV), which is thought to be related to posttransfusion hepatitis, was discovered. The aim of the present study was to investigate the prevalence and clinical significance of 2 SENV variants (SENV-D and SENV-H) in patients with hepatocellular carcinoma (HCC) and healthy adults. Also, to investigate the possible effect of SEN virus on the humoral immune response against different proteins of HCV through analyzing reactivity patterns of the confirmatory INNO-LIA HCV Ab III update in relation to SEN viremia. We investigated SEN virus infection in 41 patients with HCC (25 males and 16 females) and twenty healthy blood donors (12 males and 8 females). All samples were taken from the National Cancer Institute, Cairo University. We used semi nested polymerase chain reaction (PCR) amplification to detect SENV-D and SENV-H strains in serum. All patients were tested against HCV antibody by ELISA and HCV viremia by RT-PCR. Furthermore, nineteen patients positive for HCV antibody by EIA (10 positive for SEN DNA and 9 non viremic for SEN) were confirmed in the immunoblot assay. SENV DNA was detected in 68 % (28 of 41) of patients with HCC and in 64 % (21 of 33) HCV-related HCC, in comparison to 5% (1 of 20) healthy blood donor populations. The blood biochemical parameters, and performance status did not differ significantly between the SENV DNA-positive and- negative patients. However, the overall survival rate was 50 % after two years follow up in SENV DNA-positive and 14 % in SENV DNA-negative HCC patients. Reactivity to NS5 and E2 were less (22 % and 44 % of cases) in SENV negative cases, than in SENV positive cases (70 % and 80 % of cases, respectively). In conclusion, SENV DNA seems to be highly prevalent among Egyptian HCC patients. Cross reactivity between SENV proteins and HCV NS5, E2 or the increased immune response in SENV positive cases and consequently the increased reactivity to HCV NS5 and E2 proteins could not be ruled out. Although there was no apparent effect of SENV on biochemical tests, survival rates of SENV DNA-positive HCC patients were higher thannegative cases, which might be due to other factors affecting survival in our Egyptian HCC patients.     

Colonic Manometry Catheter Placement with Primary Fluoroscopic Guidance

The purpose of this paper is to describe our experience with a new technique of colonic manometry catheter placement using fluoroscopic guidance. Between 2000 and 2004, 44 colonic manometry catheters were placed with primary fluoroscopic guidance in 38 patients (25 males; median age, 7 years; range, 0.4–31 years) with severe defecation disorders. Fourteen colonoscopic placements were reviewed to compare the different procedures. Manometry catheters were inserted through the rectum (16 patients), cecostomy (9), ileostomy (2), and colostomy (17). Placements through diverted colons were successful in 24 of 28 (86%). Insertion through the rectum was successful in 10 of 16 (63%) fluoroscopic-guided placements vs. 12 of 14 (86%) colonoscopic placements (P=0.23). Significantly longer fluoroscopic exposure was required for fluoroscopic compared to colonoscopic placement (P=0.004). In conclusion, placement of colonic manometry catheters with primary fluoroscopic guidance is feasible in children. An important disadvantage of the fluoroscopic methodology is the prolonged fluoroscopic exposure time.     

Evaluating regional blood spinal cord barrier dysfunction following spinal cord injury using longitudinal dynamic contrast-enhanced MRI

Background  

In vivo preclinical imaging of spinal cord injury (SCI) in rodent models provides clinically relevant information in translational research. This paper uses multimodal magnetic resonance imaging (MRI) to investigate neurovascular pathology and changes in blood spinal cord barrier (BSCB) permeability following SCI in a mouse model of SCI.     

Fine-needle aspiration diagnosis of squamous cell carcinoma in a lymph node involved with small lymphocytic lymphoma: case report and review of the literature

Diagnosis of two distinct malignant entities existing concurrently and at the same location (synchronous malignancy) by fine- needle aspiration (FNA) is unusual but may occur. Small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) in particular is associated with an increased incidence of secondary tumor, likely due to associated immunodeficiency. Co-occurrence of some carcinomas such as squamous cell carcinoma (SCC), may show especially aggressive behavior. A 57-year-old Caucasian male presented with recurrent upper extremity lymphedema and diffuse lymphadenopathy of the axillary and cervical regions. FNA of a large cervical lymph node was diagnostic for both atypical lymphocytic proliferation and SCC. Flow cytometric analysis showed the atypical lymphocytic proliferation to be positive for CD5, CD23, CD19, CD20, HLA-DR, CD38, and the population was kappa light chain restricted. These cells were negative for CD-10 and FMC-7 antigens, suggesting a phenotype of B-cell SLL/CLL. We report a rare occurrence of metastatic SCC to a lymph node infiltrated by SLL/CLL. The diagnosis was achieved by a combination of cytomorphologic examination of FNA smears, immunohistochemical staining of cell block material, and flow cytometry on the sample obtained by FNA. To the best of our knowledge, only three cases of SCC metastasis to SLL/CLL diagnosed by FNA have been reported in the English literature. Though rare, awareness of such a possibility and careful cytological examination under the appropriate clinical conditions is warranted.     

Serum levels of β-catenin as a potential marker for genotype 4/hepatitis C-associated hepatocellular carcinoma

The global rising incidence of hepatocellular carcinoma (HCC), which parallels the increase of hepatitis C virus (HCV) prevalence, has sparked a renewed interest in discovering additional HCC serum markers. In this study, we investigated the clinical use of serum E-cadherin, ICAM, MMP-2, VEGF, OPN and β-catenin as potential diagnostic makers for HCV/genotype 4-associated HCC. Twenty cases of healthy subjects, 11 cases with asymptomatic HCV/genotype 4 carriers (ASC), 28 chronic hepatitis (CH) cases and 32 patients with HCC were enrolled in this study. Serum levels of proteins were measured by a sandwich-enzyme-linked (ELISA) assay. The diagnostic accuracy of each candidate marker was evaluated using receiver-operating characteristic (ROC) curve analysis, reporting the area under the curve (AUC) and its 95% confidence interval (CI). We demonstrated that serum β-catenin levels were significantly elevated in patients with HCC compared to those with CH, ASC and healthy controls. Among the six studied markers, β-catenin was also found to be the only marker that can significantly discriminate between patients with HCC and those with CH; therefore, β-catenin could be considered as a potential marker for early diagnosis of HCV-associated HCC in patients infected with HCV genotype 4.     

Performance Comparison of GeneXpert MTB/RIF and ProbeTec ET Tests for Rapid Molecular Diagnosis of Extrapulmonary Tuberculosis in a Low TB/MDR-TB Incidence Country

ObjectiveThis study evaluated the performance of GeneXpert MTB/RIF (Xpert) and ProbeTec ET (PTec-ET) assays in diagnosing extrapulmonary tuberculosis (EPTB) in Kuwait.Materials and MethodsWe tested nonrespiratory clinical specimens (n = 3,995) collected from 3,995 patients suspected to have EPTB. These included cavitary fluids (n = 2,054), fine-needle aspirate (FNA)/pus/tissue biopsy (n = 1,461), urine (n = 302), cerebrospinal fluid (CSF, n = 118), and others (n = 60). All specimens were processed for acid-fast bacilli (AFB), culture in mycobacteria growth indicator tube 960 system, and nucleic acid detection by Xpert and PTec-ET according to manufacturer''s instructions.ResultsOf 3,995 specimens, 95 were AFB-positive, 403 were culture-positive, and an additional 86 samples had histopathology suggestive of TB. Using culture as reference, the sensitivity and specificity values were 88.33 and 97.3% for Xpert and 72.95 and 97.80% for PTec-ET, respectively. Although performance of both tests was comparable in AFB-positive samples, Xpert detected significantly more cases in culture-positive samples. Among culture-negative samples, Xpert detected 18 more cases including 16 with histopathological evidence of TB. Lowest positivity was detected for both tests in cavitary fluids. Xpert performed better than PTec-ET in culture-positive FNA/pus/tissue biopsy and CSF samples.ConclusionsAlthough performance of both tests was suboptimal for AFB-negative/culture-positive samples, Xpert performed better than PTec-ET and also detected more cases of AFB-negative/culture-negative/histopathology-positive samples. PTec-ET was positive in 3, while Xpert was positive in all 6 culture-positive CSF specimens for rapid diagnosis of TB meningitis. Xpert was thus superior to PTec-ET or smear microscopy in rapid diagnosis of EPTB.