Comparison of cryobiopsy and forceps biopsy for the diagnosis of mediastinal lesions: A randomised clinical trial.

INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the standard approach for lung cancer staging. However, its diagnostic utility for other mediastinal diseases might be hampered by the limited tissue retrieved. Recent evidence suggests the novel sampling strategies of forceps biopsy and cryobiopsy as auxiliary techniques to EBUS-TBNA, considering their capacity for larger diagnostic samples. METHODS: This study determined the added value of forceps biopsy and cryobiopsy for the diagnosis of mediastinal diseases. Consecutive patients with mediastinal lesions of 1 cm or more in the short axis were enrolled. Following completion of needle aspiration, three forceps biopsies and one cryobiopsy were performed in a randomised pattern. Primary endpoints included diagnostic yield defined as the percentage of patients for whom mediastinal biopsy led to a definite diagnosis, and procedure-related complications. RESULTS: In total, 155 patients were recruited and randomly assigned. Supplementing EBUS-TBNA with either forceps biopsy or cryobiopsy increased diagnostic yield, with no significant difference between EBUS-TBNA plus forceps biopsy and EBUS-TBNA plus cryobiopsy (85.7 % versus 91.6 %, P = 0.106). Yet, samples obtained by additional cryobiopsies were more qualified for lung cancer molecular testing than those from forceps biopsies (100.0 % versus 89.5 %, P = 0.036). When compared directly, the overall diagnostic yield of cryobiopsy was superior to forceps biopsy (85.7 % versus 70.8 %, P = 0.001). Cryobiopsies produced greater samples in shorter procedural time than forceps biopsies. Two (1.3 %) cases of postprocedural pneumothorax were detected. CONCLUSIONS: Transbronchial mediastinal cryobiopsy might be a promising complementary tool to supplement traditional needle biopsy for increased diagnostic yield and tissue harvesting. TRIAL REGISTRATION: ChiCTR2000030373.

Investigating Effects of Mentoring for Youth with Assault Injuries: Results of a Randomized-Controlled Trial.

Mentoring is considered an evidence-based practice for violence prevention. This study presents a partial replication of the Take Charge! program implemented in partnership with Big Brothers Big Sisters of America (BBBS). One hundred and eighty-eight early adolescents (M age = 12.87; 61.17% male) who were treated for peer-related assault injury in two urban mid-Atlantic emergency departments were randomly assigned to receive a mentor from two BBBS affiliates. Mentors and organization staff were trained in the Take Charge! violence prevention curriculum, which had previously shown evidence of efficacy. Intent-to-treat analyses showed statistically significant improvements in conflict avoidance self-efficacy for the intervention group at 9 months and reductions in fighting at 21 months, but an increase in parental report of aggression at 9 months. Complier average causal effect models revealed evidence of an additional effect for reduced problem behavior at 21 months for intervention adolescents who received a mentor. No effects were found for youth-reported aggression, retaliatory attitudes, deviance acceptance, or commitment to learning. Sensitivity analyses suggested increased aggressive behavior for adolescents in the intervention group who did not receive a mentor (i.e., non-compliers). These findings extend the evidence-base for Take Charge! as a violence prevention curriculum for youth already engaged in violence to "real-world" implementation settings. However, they also suggest that challenges associated with providing youth with mentors can be consequential and that additional supports may be needed for these youth/parents. Clinical trials number: clinicaltrials.gov NCT01770873.

Induction of periosteal bone formation by intraosseous BMP-2 injection in a mouse model of osteogenesis imperfecta.

PURPOSE: Surgical interventions are routinely performed on children with osteogenesis imperfecta (OI) to stabilize long bones, often post fracture. We speculated that a combination of intramedullary reaming and intraosseous injection of recombinant bone morphogenetic protein-2 (BMP-2) could enhance periosteal ossification and ultimately cortical thickness and strength. This approach was conceptually tested in a preclinical model of genetic bone fragility. METHODS: Six experimental groups were tested including no treatment, intramedullary reaming, and reaming with 5 µg BMP-2 injection performed in the tibiae of both wild type (WT) and Col1a2 G610C/+ (OI, Amish mutation) mice. Bone formation was examined at a two-week time point in ex vivo specimens by micro-computed tomography (microCT) analysis and histomorphometry with a dynamic bone label. RESULTS: MicroCT data illustrated increases in tibial cortical thickness with intramedullary reaming alone (Saline) and reaming plus BMP-2 injection (BMP-2) compared to no intervention controls. In the OI mice, the periosteal bone increase was not statistically significant with Saline but there was an increase of +192% (p = 0.053) with BMP-2 injection. Dynamic histomorphometry on calcein label was used to quantify new woven bone formation; while BMP-2 induced greater bone formation than Saline, the anabolic response was blunted overall in the OI groups. CONCLUSIONS: These data indicate that targeting the intramedullary compartment via reaming and intraosseous BMP-2 delivery can lead to gains in cortical bone parameters. It is suggested that the next step is to validate safety and functional improvements in a clinical OI setting.

Establishment of feline in-house reference intervals for hematologic and biochemical parameters and potential age-related differences.

Reference intervals (RIs) are one of the essential elements in the procedure of disease diagnosis. This is especially true for feline species in which RI is less available than in canine species. RIs are affected by biological, geographical and instrumental factors, yet published RIs with incomplete background are popularly used. Inappropriate interpretations of RIs may affect classification of disease and subsequent treatment. In this study, we demonstrated the step-by-step establishment of feline RIs following the American Society for Veterinary Clinical Pathology (ASVCP) reference interval guideline. A total of 51 parameters were examined, including 20 hematology and 31 biochemistry parameters, and the results were compared to one local RI and two foreign RIs. Overall, about 29% (10/35) of tested parameters were different form local RIs and 60% (30/50) were different from the two foreign RIs, highlighting geographical variations. A higher upper reference limit (URL) in red blood cell count (RBC), hematocrit (Hct), Hemoglobin (Hgb), albumin, creatinine and lower URL in potassium and white blood cell count (WBC) were identified, which may impact the interpretation. In addition, statistical analysis of age and gender were factored separately and indicated that 10 parameters were significantly higher in the adult group. For the impact of gender, percentage of basophil and total iron-binding capacity (TIBC) were lower in female and male cats, respectively. In conclusion, we have demonstrated that it is desirable to establish in-house RIs or RIs of local sources. An age specific RI for the geriatric feline population is advisable for better diagnosis and monitoring the disease.

Continuous compression behaviors of selective laser melting Ti-6Al-4V alloy with cuboctahedron cellular structures.

Cellular structures often show fluctuating stresses in compression stress-strain curves. Such fluctuating stresses correspond to strut fractures. In this study, the cellular Ti-6Al-4V alloy with cuboctahedron structure was prepared by selective laser melting. The cuboctahedron cellular structures showed reduced fluctuations in their compressive stress-strain curves after the initial yielding peak. Their moduli were modulated via the porosity of the structure by changing the strut diameter. A compressive modulus of between 1.3 and 4.868 GPa can be achieved by varying the porosity in the cellular structures between 33% and 84%. Both heat treatment and hot isostatic press (HIP) treatment reduced the fracture strength of the struts during compression due to the conversion of the α' martensite phase into the more ductile α +â€¯ß phase. The cellular structure with HIP treatment produced a continuous stress-strain curve during compression, indicating uniform strain distribution behavior. The continuous compressive stress-strain curve can lead to reduced debris formation during compression processes. The deformation showed either bending or stretching mechanisms depending on whether the supports were included along the building direction. The design concepts of cellular structures demonstrated in this study will be valuable in future biomedical applications.

Cannulated screw versus Kirschner-wire fixation for Milch II lateral condyle fractures in a paediatric sawbone model: a biomechanical comparison.

PURPOSE: Lateral condyle fractures of the humerus are common in the paediatric population, accounting for up to 20% of elbow fractures. Traditional management involves internal fixation with Kirschner (K)-wires, however, this has been associated with complications and insufficiently rigid fixation. Recently, cannulated screws have been proposed as a more stable method of fixation. While cannulated screws have been thought to allow earlier range of movement and shorten time to union, data regarding the biomechanical performance and optimal screw placement is scarce. We hypothesize that cannulated screw fixation is superior to K-wire fixation and screw placement can enhance the stability of the construct. METHODS: Paediatric humerus sawbones with Milch II fractures were fixed with one of three methods. Fractures were reduced with either a single cannulated screw either through the centre of the capitellum (oblique), or placed up the lateral column across the growth plate (lateral), or fixed with two K-wires. Fixed sawbone fractures were then mechanically tested in two directions simulating in vivo forces. RESULTS: The lateral screw construct had a higher maximum force to failure, higher stiffness and absorbed higher energy as compared with the K-wire fixation and oblique screw under an anterior force. When loaded from the posterior direction, only the lateral column screw was better than K-wire fixation. CONCLUSIONS: Screw fixation is a biomechanically effective alternative to K-wire fixation, especially when placed up the lateral column of the distal humerus. Further clinical studies are required before transcapitellar screw fixation can be adopted.

[Role of miR-155 in invasion and metastasis of lung adenocarcinoma A549 cells].

OBJECTIVE: To investigate the role and mechanism of miR-155 in invasion and metastasis of lung adenocarcinoma A549 cells. METHODS: Real-time PCR and fluorescence in situ hybridization were used to detect the miR-155 expression in patients' lung adenocarcinoma and adjacent tissue and lymph nodes. Scratch test and Transwell migration assay were used to assess the effect of miR-155 on the A549 cell migration and invasion capability. Bioinformatics software was used to predict the target genes of miR-155, and using luciferase to assay the target gene. Western blot and real-time PCR were performed to confirm the role of miR-155 expression in the regulation of target gene PTEN. RESULTS: The real-time quantitative PCR showed that the miR-155 expression levels in adjacent normal tissue, lung adenocarcinoma and metastatic lymph nodes were 4.1±0.5, 9.6±3.1 and 7.8±2.2, respectively. The in situ hybridization showed that the expression rates of miR-155 in the adjacent normal tissue, lung adenocarcinoma and metastatic lymph nodes were (23.2±15.3)%, (75.4±20.2)% and (60.4±25.1)%, respectively. The Scratch assay showed that the wound healing rates in the miR-155 mimics group, miR-155 mimics NC group, miR-155 inhibitor group and miR-155 inhibitor NC group at 24 h were (43.2±2.2)%, (21.3±4.2)%, (24.3±5.3)%, and (35.2±5.1)%, and that at 48 h were (75.2±4.5)%, (52.6±5.2)%, (39.4±4.2)%, and (51.5±4.3)%, respectively. Dual luciferase reporter gene assay showed that the value of the luciferase in the miR-155 mimics group co-transfected with PTEN 3'UTR-containing wild-type and mutant plasmids were 4.7±0.5 and 7.3±0.7, and the miR-155 mimics luciferase values of the control group co-transfected with PTEN 3'UTR-containing wild-type and mutant plasmids were 7.8±0.9 and 7.5±0.8, respectively. The real-time quantitative fluorescence PCR showed that the relative expression of PTEN protein in the miR-155 mimics group, miR-155 mimics control group, miR-155 mimics inhibitor group, and miR-155 inhibitor control group were 0.5±0.3, 1.0±0.1, 2.2±0.2 and 1.2±0.1, respectively. The Western blot assay detected that the relative expression of PTEN protein levels in the miR-155 mimics group, miR-155 mimics control group, miR-155 inhibitor group and miR-155 inhibitor control group were 0.4±0.1, 1.0±0.3, 2.8±0.2 and 1.4±0.1, respectively. The differences in PTEN mRNA and protein expressions of the four groups were statistically significant (P<0.05 for all). CONCLUSIONS: miR-155 may promote the invasion and metastasis of lung adenocarcinoma through reducing the target PTEN gene expression.

The combination of the prodrugs perforin-CEBPD and perforin-granzyme B efficiently enhances the activation of caspase signaling and kills prostate cancer.

The survival of prostate cancer (PrCa) patients is associated with the transition to hormone-independent tumor growth and metastasis. Clinically, the dysregulation of androgen action has been associated with the formation of PrCa and the outcome of androgen deprivation therapy in PrCa. CCAAT/enhancer binding protein delta (CEBPD) is a transcription factor that has been reported to act as an oncogene or tumor suppressor, depending on the extra- and intracellular environments following tumorigenesis. We found that androgen can activate CEBPD transcription by direct binding of the androgen receptor (AR) to the CEBPD promoter region. Increases of suppressor of zeste 12 (SUZ12) and enhancer of zeste homolog 2 (EZH2) attenuated the androgen-induced transcription of CEBPD. Importantly, the increases in E2F1, SUZ12 and EZH2 as well as the inactivation of CEBPD were associated with the clinicopathological variables and survival of PrCa patients. We revealed that caspase 8 (CASP8), an apoptotic initiator, is responsive to CEBPD induction. Reporter and in vivo DNA-binding assays revealed that CEBPD directly binds to and activates CASP8 reporter activity. A prodrug system was developed for therapeutic application in AR-independent or androgen-insensitive PrCa to avoid the epigenetic effects on the suppression of CEBPD expression. Our results showed that the combination of a perforin (PF)-CEBPD prodrug (which increases the level of procaspase-8) and a PF-granzyme B prodrug (which activates CASP8 and caspase 3 (CASP3)) showed an additive effect in triggering the apoptotic pathway and enhancing apoptosis in PrCa cells.

A sugar-based phase-transitioning delivery system for bone tissue engineering.

Bone tissue engineering approaches commonly involve the delivery of recombinant human bone morphogenetic proteins (rhBMPs). However, there are limitations associated with the currently used carriers, including the need for surgical implantation and the associated increase in infection risk. As an alternative to traditional porous collagen sponge, we have adopted a solution of the injectable sucrose acetate isobutyrate (SAIB) as a carrier for rhBMP-2. The ability to deliver rhBMP-2 and other agents by injection reduces the infection risk and lesion size whilst in surgery, with the potential to avoid open surgery altogether in some indications. The primary methodology used for this in vivo study was a C57BL6/J mouse ectopic bone formation model. Specimens were examined by x-ray, microCT, and histology at 3 weeks. SAIB was delivered non-invasively and produced up to 3-fold greater bone volume compared to collagen. To further refine and improve upon the formulation, SAIB containing rhBMP-2 was admixed with candidate compounds including ceramic microparticles, anti-resorptives, and cell signalling inhibitors and further tested in vivo. The formulation combining SAIB/rhBMP-2, the bisphosphonate zoledronic acid (ZA), and hydroxyapatite (HA) microparticles yielded a 10-fold greater bone volume than SAIB/rhBMP-2 alone. To investigate the mechanism underlying the synergy between ZA and HA, we used in vitro binding assays and in vivo fluorescent biodistribution studies to demonstrate that ceramic particles could bind and sequester the bisphosphonate. These data show the utility of SAIB as a non-invasive rhBMP delivery system as well as describing an optimised formulation for bone tissue engineering.

Expression of ß-glucuronidase on the surface of bacteria enhances activation of glucuronide prodrugs.

Extracellular activation of hydrophilic glucuronide prodrugs by ß-glucuronidase (ßG) was examined to increase the therapeutic efficacy of bacteria-directed enzyme prodrug therapy (BDEPT). ßG was expressed on the surface of Escherichia coli by fusion to either the bacterial autotransporter protein Adhesin (membrane ßG (mßG)/AIDA) or the lipoprotein (lpp) outermembrane protein A (mßG/lpp). Both mßG/AIDA and mßG/lpp were expressed on the bacterial surface, but only mßG/AIDA displayed enzymatic activity. The rate of substrate hydrolysis by mßG/AIDA-BL21cells was 2.6-fold greater than by pßG-BL21 cells, which express periplasmic ßG. Human colon cancer HCT116 cells that were incubated with mßG/AIDA-BL21 bacteria were sensitive to a glucuronide prodrug (p-hydroxy aniline mustard ß-D-glucuronide, HAMG) with an half maximal inhibitory concentration (IC50) value of 226.53±45.4 µM, similar to the IC50 value of the active drug (p-hydroxy aniline mustard, pHAM; 70.6±6.75 µM), indicating that mßG/AIDA on BL21 bacteria could rapidly and efficiently convert HAMG to an active anticancer agent. These results suggest that surface display of functional ßG on bacteria can enhance the hydrolysis of glucuronide prodrugs and may increase the effectiveness of BDEPT.

Circulating tumor cells as a surrogate marker for determining clinical outcome to mFOLFOX chemotherapy in patients with stage III colon cancer.

BACKGROUND: This study was aimed to detect post-chemotherapeutic circulating tumour cells (CTCs) in stage III colon cancer patients and identify those who were at high risk of relapse. METHODS: We used human telomerase reverse transcriptase, cytokeratin-19, cytokeratin-20, and carcinoembryonic antigen (CEA) as the biomarkers to detect CTCs in 90 stage III colon cancer patients undergoing curative resection followed by mFOLFOX chemotherapy. RESULTS: Post-chemotherapeutic relapse occurred in 30 (33.3%) patients. By univariate analysis and multivariate proportional hazards regression analysis, perineural invasion (hazard ratio (HR): 2.752; 95% confidence interval (CI): 1.026-7.381), high post-chemotherapeutic serum CEA levels (HR: 2.895; 95% CI: 1.143-7.333) and persistent presence of post-chemotherapeutic CTCs (HR: 6.273; 95% CI: 2.442-16.117) were independent predictors of post-chemotherapeutic relapse. In addition, the persistent presence of post-chemotherapeutic CTCs strongly correlated with reduced disease-free survival and overall survival. Accuracy of detecting relapse in post-chemotherapeutic stage III colon cancer patients by analysing the persistent presence of post-chemotherapeutic CTCs was higher than that by post-chemotherapeutic CEA levels (odds ratio: 50.091 vs 5.211). CONCLUSION: The persistent presence of post-chemotherapeutic CTCs is a potential powerful surrogate marker for determining clinical outcome in stage III colon cancer patients receiving adjuvant mFOLFOX chemotherapy.

Enhancement of CPT-11 antitumor activity by adenovirus-mediated expression of ß-glucuronidase in tumors.

CPT-11 is a clinically important prodrug that requires conversion into the active metabolite SN-38, a potent topoisomerase I poison, for antitumor activity. However, SN-38 is rapidly metabolized to the inactive SN-38 glucuronide (SN-38G) in the liver, which reduces the amount of SN-38 available for killing cancer cells. Here, we investigated if local expression of ß-glucuronidase (ßG) on cancer cells to catalytically convert SN38G to SN38 could enhance the antitumor activity of CPT-11. ßG was tethered on the plasma membrane of three different human cancer cell lines: human colon carcinoma (LS174T), lung adenocarcinoma (CL1-5) and bladder carcinoma (EJ). Surface ß-glucuronidase-expressing cells were 20 to 80-fold more sensitive to SN-38G than the parental cells. Intravenous CPT-11 produced significantly greater suppression of CL1-5 and LS174 T tumors that expressed ßG as compared with unmodified tumors. Furthermore, an adenoviral vector expressing membrane-tethered ßG (Ad.ßG) increased the sensitivity of cancer cells to SN-38G even at multiplicity of infections as low as 0.16, indicating bystander killing of non-transduced cancer cells. Importantly, intratumoral injection of Ad.ßG significantly enhanced the in vivo antitumor activity of CPT-11 as compared with treatment with CPT-11 or Ad vectors alone. This study shows that Ad.ßG has potential to boost the therapeutic index of CPT-11.

Multitarget therapy of malignant cancers by the head-to-tail tandem array multiple shRNAs expression system.

Coexpression of multiple shRNAs can simultaneously inhibit multiple genes or target multiple sites on a single gene. These approaches can be used for dissecting complex signaling pathways and even be applied to targeting multiple genes in cancer therapy. Here we established a simple and efficient multiple shRNAs expression system based on pSUPER, the most popular expression vector in mammalian cells. A series of head-to-tail tandem array multiple shRNAs expression vectors were constructed containing different combinations of six shRNA expression cassettes targeting genes involved in cell proliferation and survival pathways: Bcl-2, Survivin, Akt1, Erk2, CyclinE and NFkappaB. In HeLa and HEK293 cells, the multiple shRNAs expression constructs could efficiently and simultaneously induce inhibition of all six genes. We further evaluated the inhibition effects of the multiple shRNAs expression vectors on the human prostate cancer cell line PC3, which contains different cell variants with distinct oncogenic signaling alterations. The results revealed that the multiple shRNAs expression system could inhibit all six genes and was much more efficient in inducing apoptosis in the PC3 cells. Our results suggest that the multitarget shRNAs expression system could be an effective strategy in cancer therapy and be applied to any other DNA vector-based shRNA expression system.

Hapten-derivatized nanoparticle targeting and imaging of gene expression by multimodality imaging systems.

Non-invasive gene monitoring is important for most gene therapy applications to ensure selective gene transfer to specific cells or tissues. We developed a non-invasive imaging system to assess the location and persistence of gene expression by anchoring an anti-dansyl (DNS) single-chain antibody (DNS receptor) on the cell surface to trap DNS-derivatized imaging probes. DNS hapten was covalently attached to cross-linked iron oxide (CLIO) to form a 39+/-0.5 nm DNS-CLIO nanoparticle imaging probe. DNS-CLIO specifically bound to DNS receptors but not to a control single-chain antibody receptor. DNS-CLIO (100 microM Fe) was non-toxic to both B16/DNS (DNS receptor positive) and B16/phOx (control receptor positive) cells. Magnetic resonance (MR) imaging could detect as few as 10% B16/DNS cells in a mixture in vitro. Importantly, DNS-CLIO specifically bound to a B16/DNS tumor, which markedly reduced signal intensity. Similar results were also shown with DNS quantum dots, which specifically targeted CT26/DNS cells but not control CT26/phOx cells both in vitro and in vivo. These results demonstrate that DNS nanoparticles can systemically monitor the expression of DNS receptor in vivo by feasible imaging systems. This targeting strategy may provide a valuable tool to estimate the efficacy and specificity of different gene delivery systems and optimize gene therapy protocols in the clinic.

Tumor-targeting prodrug-activating bacteria for cancer therapy.

Increasing the specificity of chemotherapy may improve the efficacy of cancer treatment. Toward this aim, we developed a strain of bacteria to express enzymes for selective prodrug activation and non-invasive imaging in tumors. beta-glucuronidase and the luxCDABE gene cluster were expressed in the DH5alpha strain of Escherichia coli to generate DH5alpha-lux/betaG. These bacteria emitted light for imaging and hydrolyzed the glucuronide prodrug 9ACG to the topoisomerase I inhibitor 9-aminocamptothecin (9AC). By optical imaging, colony-forming units (CFUs) and staining for betaG activity, we found that DH5alpha-lux/betaG preferentially localized and replicated within CL1-5 human lung tumors in mice. The intensity of luminescence, CFU and betaG activity increased with time, indicating bacterial replication occurred in tumors. In comparison with DH5alpha-lux/betaG, 9AC or 9ACG treatment, combined systemic administration of DH5alpha-lux/betaG followed by 9ACG prodrug treatment significantly (P<0.005) delayed the growth of CL1-5 tumors. Our results demonstrate that prodrug-activating bacteria may be useful for selective cancer chemotherapy.

Adolescents as victims of familial violence: a hospital based surveillance.

Adolescent abuse is an important and understudied issue in society. The objective of this study was to examine the epidemiology of physical injuries due to maltreatment among adolescents aged 10-19 years. Subjects came from seven hospitals/trauma centres in Washington DC that were involved in the Washington DC Initiative to Reduce Infant Mortality and Prevention of Childhood Injuries Study. From 1996-1998, information was gathered about all injuries to adolescents aged 10-19 years that resulted in a visit to a participating emergency department. This paper focuses on the subset 178 adolescents aged 10-19 years who presented with physical injuries due to maltreatment. It was found that 55% of victims of abuse were female. Abuse victims were more likely to be female than those with unintentional injury. The most common injuries were contusions to the extremities (29%). Mothers were the most common perpetrators (48%). A total of 64% of victims were assaulted with an object/weapon and the most common object used was a belt. There are some similarities and some important differences between patterns of maltreatment in adolescents vs. younger children. Increased awareness of maltreatment among older children is a critical step in increasing and improving screening and prevention practices among health-care professionals.

Gene expression imaging by enzymatic catalysis of a fluorescent probe via membrane-anchored beta-glucuronidase.

Development of nonimmunogenic and specific reporter genes to monitor gene expression in vivo is important for the optimization of gene therapy protocols. We developed a membrane-anchored form of mouse beta-glucuronidase (mbetaG) as a reporter gene to hydrolyze a nonfluorescent glucuronide probe (fluorescein di-beta-D-glucuronide, (FDGlcU) to a highly fluorescent reporter to assess the location and persistence of gene expression. A functional beta-glucuronidase (betaG) was stably expressed on the surface of murine CT26 colon adenocarcinoma cells where it selectively hydrolyzed the cell-impermeable FDGlcU probe. FDGlcU was also preferentially converted to fluorescent probe by (betaG) on CT26 tumors. The fluorescent intensity in betaG-expressing CT26 tumors was 240 times greater than the intensity in control tumors. Selective imaging of gene expression was also observed after intratumoral injection of adenoviral betaG vector into carcinoma xenografts. Importantly, mbetaG did not induce an antibody response after hydrodynamic plasmid immunization of Balb/c mice, indicating that the reporter gene product displayed low immunogenicity. A membrane-anchored form of human betaG also allowed in vivo imaging, demonstrating that human betaG can be employed for imaging. This imaging system therefore, displays good selectivity with low immunogenicity and may help assess the location, magnitude and duration of gene expression in living animals and humans.

Membrane-localized activation of glucuronide prodrugs by beta-glucuronidase enzymes.

Gene-mediated enzyme prodrug therapy (GDEPT) seeks to increase the therapeutic index of anti-neoplastic agents by promoting selective activation of relatively nontoxic drug derivatives at sites of specific enzyme expression. Glucuronide prodrugs are attractive for GDEPT due to their low toxicity, bystander effect in the interstitial tumor space and the large range of possible glucuronide drug targets. In this study, we expressed human, murine and Esherichia coli beta-glucuronidase on tumor cells and examined their in vitro and in vivo efficacy for the activation of glucuronide prodrugs of 9-aminocamptothecin and p-hydroxy aniline mustard. We show that (1) fusion of beta-glucuronidase to the Ig-like C(2)-type and Ig-hinge-like domains of the B7-1 antigen followed by the B7-1 transmembrane domain anchored high levels of active murine and human beta-glucuronidase on cells, (2) strong bystander killing of tumor cells was achieved in vitro by murine beta-glucuronidase activation of prodrug, (3) potent in vivo anti-tumor activity was achieved by prodrug treatment of tumors that expressed murine beta-glucuronidase and (4) the p-hydroxy aniline prodrug was more effective in vivo than the 9-aminocamptothecin prodrug. Our results demonstrate that surface expression of murine beta-glucuronidase for activation of a glucuronide prodrug of p-hydroxy aniline mustard may be useful for more selective therapy of cancer.

Molecular detection of disseminated tumor cells in the peripheral blood of patients with gastric cancer: evaluation of their prognostic significance.

Early detection of disseminated tumor cells in the peripheral blood of patients with early stage gastric cancer could help to improve the outcome after tumor resection. The aim of this study is to evaluate the prognostic significance of tumor-related mRNA for the detection of circulating tumor cells in gastric cancer patients by a reverse-transcriptase polymerase chain reaction (RT-PCR) method. We simultaneously analyzed human telomerase reverse transcriptase (hTERT), cytokeratin-19 (CK-19), cytokeratin-20 (CK-20) and carcinoembryonic antigen (CEA) mRNA (messenger RNA) expression in the peripheral blood of 42 gastric cancer patients and 30 healthy individuals. Additionally, analyses were carried out for the correlation of these four molecular markers with patients' clinicopathologic features, as well as the occurrence of postoperative recurrence/metastasis. Among 42 gastric cancer patients, the prevalence of mRNA for hTERT, CK-19, CK-20, and CEA was 61.9% (26/42), 69% (29/42), 61.9% (26/42), and 78.6% (33/42), respectively. All 30 healthy individuals were negative for hTERT and CEA mRNA, while two were positive for either CK-19 mRNA or CK-20 mRNA. Positive CEA mRNA was significantly correlated with tumor size p=0.008), vessel invasion (p=0.001), depth of tumor invasion (p=0.007), lymph node metastasis (p< 0.001), and TNM stage (p<0.001). In addition, the multivariate logistic regression demonstrated that CEA mRNA expression was an independent and significant predictor for postoperative recurrence/metastasis (p=0.032). Our findings suggest that CEA mRNA may be a more reliable marker than hTERT, CK-19 and CK-20 for the detection of circulating cancer cells in gastric cancer patients' peripheral blood. Patients with positive CEA mRNA expression in peripheral blood have a significantly higher risk of postoperative recurrence/metastasis.

The spectrum of intoxication and poisonings among adolescents: surveillance in an urban population.

AIM: Among adolescents, poisoning is a leading cause of injury mortality in the United States. This study describes the epidemiology of poisonings, intoxication, and maladaptive effects of drugs among adolescents age 10-19 years in a large city. METHODS: An injury surveillance system used records at seven hospitals, medical examiner records, and vital records over a two year period. RESULTS: Of 633 cases (618 injuries/100 000/year), 6% were unintentional, 36% self-inflicted, 41% alcohol intoxication, and 15% maladaptive effects of drugs. Alcohol was involved in 45% of cases, 23% illegal drugs, 23% non-prescription drugs, 19% prescription drugs; 19% involved more than one substance. Hospitalization was required in 20%; 8% transferred to another hospital; one died from intoxication. The authors found high rates of self-inflicted poisoning, intoxication, and maladaptive effects of drugs among this urban population. CONCLUSION: The study highlights the need to broadly define poisonings among adolescents and the challenge of assessing intent in some cases.