The effect of TISSEEL fibrin sealant on seroma formation following complex abdominal wall hernia repair: a single institutional review and derived cost analysis.

PURPOSE: The authors evaluated the ability of a fibrin sealant (TISSEEL™: Baxter Healthcare Corp, Deerfield, IL, USA) to reduce the incidence of post-operative seroma following abdominal wall hernia repair. METHODS: We performed a 4-year retrospective review of patients undergoing abdominal wall hernia repair, with and without TISSEEL, by a single surgeon (FEE) at The Johns Hopkins Hospital. Demographics, surgical risk factors, operative data and 30-day outcomes, including wound complications and related interventions, were compared. The quantity and cost of Tisseel per case was reviewed. RESULTS: A total of 250 patients were evaluated: 127 in the TISSEEL group and 123 in the non-TISSEEL control group. The average age for both groups was 56.6 years (P = 0.97). The majority of patients were female (TISSEEL 52.8%, non-TISSEEL 56.1%, P = 0.59) and ASA Class III (TISSEEL 56.7%, non-TISSEEL 58.5%, P = 0.40). There was no difference in the average defect size for both groups (TISSEEL 217 ± 187.6 cm(2), non-TISSEEL 161.3 ± 141.5 cm(2), P = 0.36). Surgical site occurrences occurred in 18.1% of the TISSEEL and 13% of the non-TISSEEL group (P = 0.27). There was a trend towards an increased incidence of seroma in the TISSEEL group (TISSEEL 11%, non-TISSEEL 4.9%, P = 0.07). A total of $124,472.50 was spent on TISSEEL, at an average cost of $995.78 per case. CONCLUSIONS: In the largest study to date, TISSEEL™ application offered no advantage for the reduction of post-operative seroma formation following complex abdominal hernia repair. Moreover, the use of this sealant was associated with significant costs.

A polyethylenimine-mimetic biodegradable polycation gene vector and the effect of amine composition in transfection efficiency.

The low toxicity and efficient gene delivery of polymeric vectors remain the major barrier to the clinical application of non-viral gene therapy. Here, we present a poly-D, L-succinimide (PSI)-based biodegradable cationic polymer which mimicked the golden standard, branched polyethylenimine (PEI, ~25 kDa). To investigate the influence of 1°, 2°, 3° amine group ratio in the polymer, a series of PSI-based vectors (PSI-NN'x-NNy) grafted with different amine side chains of N,N-dimethyldipropylenetriamine (NN') and bis(3-aminopropyl)amine (NN) were first characterized and contrasted by biophysical measurements. The in vitro and in vivo biological assay demonstrated that PSI-NN'0.85-NN1 exhibited better transfection ability and biocompatibility than PEI. The present results suggest that such PEI-mimic biodegradable PSI-NN'0.85-NN1 possesses a good potential application for clinical gene delivery.

Cationic microRNA-delivering nanovectors with bifunctional peptides for efficient treatment of PANC-1 xenograft model.

Therapeutic strategies based on modulation of microRNA activity possess much promise in cancer therapy, but the in vivo delivery of microRNA to target sites and its penetration into tumor tissues remain great challenge. In this work, miR-34a-delivering therapeutic nanocomplexes with a tumor-targeting and -penetrating bifunctional CC9 peptide were proposed for efficient treatment of pancreatic cancers. In vitro study indicated that the nanoparticle-based miR-34a delivery systems could effectively facilitate cellular uptake and greatly up-regulate the mRNA level of miR-34a in PANC-1 cell lines. The up-regulation of miR-34a remarkably induced cell cycle arrest and apoptosis, suppressed the tumor cell migration and inhibited the target gene expressions such as E2F3, Bcl-2, c-myc and cyclin D1. More importantly, the in vivo systemic administration of the developed targeting miR-34a delivery systems in a pancreatic cancer model significantly inhibited tumor growth and induced cancer cell apoptosis. Such bifunctional peptide-conjugated miRNA-delivering nanocomplexes should have great potential applications in cancer therapy.

A gene nanocomplex conjugated with monoclonal antibodies for targeted therapy of hepatocellular carcinoma.

To enhance tumor-targeting abilities and therapeutic efficiency, a monoclonal antibody-conjugated gene nanocomplex was herein designed. The biodegradable cationic polyethylenimine-grafted-α,ß-poly(N-3-hydroxypropyl)-DL-aspartamide (PHPA-PEI) was used for complexing pDNA to form the PHPA-PEI/pDNA nanoparticle, and then 9B9 mAb, an anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibody, was conjugated to produce the PHPA-PEI/pDNA/9B9 mAb (PP9mN) complex. The PP9mN complex with the diameter of around 300 nm at its optimal weight ratio could be uptaken effectively by SMMC-7721 cells. The cytotoxicity of the PP9mN complex was much lower than that of PEI 25 kD in SMMC-7721, HepG2, Bel-7404 and COS-7 cell lines. The PP9mN complex possessed the highly efficient in vitro gene delivery ability to the hepatocellular carcinoma cells. The in vivo gene expression indicated that PP9mN could target to the tumor tissues effectively. By using the therapeutic AChE gene, it was found that the PP9mN complexes significantly enhanced the anti-tumor effect on tumor-bearing nude mice. Such monoclonal antibody-conjugated gene complex should have great potential applications in liver cancer therapy.

Detection and identification of avian, duck, and goose reoviruses by RT-PCR: goose and duck reoviruses are part of the same genogroup in the genus Orthoreovirus.

A reverse transcription-polymerase chain reaction (RT-PCR) procedure for the detection of avian, duck, and goose reovirus (ARV, DRV, and GRV) RNA from cell culture supernatant and clinical samples was established. Based on multiple sequence alignment, a pair of degenerate primers was selected and synthesized. The amplified, cloned, and sequenced 598-base-pair products from the sigmaA-encoding gene fragment from 16 isolates (ranging over 30 years) indicated that the primer regions were well conserved. The sensitivity of this method was determined to be 10(-2) PFU. The specificity of the RT-PCR method was determined by testing specimens containing avian influenza A viruses, Newcastle disease virus, and infectious bronchitis virus, all of which yielded negative results with no discernible background. The efficiency of the system for detection of ARV, DRV, and GRV directly in 71/83 clinical samples was confirmed. The nucleotide sequence analysis indicated that DRV and GRV isolated from China in different locales and years were closely related, showing 97.4-100% homology to each other, but with only 86.7-88.5% identity to DRV 89026. The nucleotide and amino acid sequence identities in the amplified sigmaA-encoding gene were 74.2-78.4% and 86.9-92.0%, respectively, between duck/goose and chicken species. Phylogenetic analysis indicated that GRV and DRV aggregated into the same specified genogroup within subgroup II of the genus Orthoreovirus and are more closely related to ARV than to Nelson Bay virus. Overall, this study developed a sensitive and specific technique for the identification ARV, DRV, and GRV, and sequencing analysis has enhanced our understanding of the evolutionary relationship between ARV, DRV, and GRV.

In vitro hematopoietic and endothelial potential of flk-1(-/-) embryonic stem cells and embryos.

Mice deficient in the Flk-1 receptor tyrosine kinase are known to die in utero because of defective vascular and hematopoietic development. Here, we show that flk-1(-/-) embryonic stem cells are nevertheless able to differentiate into hematopoietic and endothelial cells in vitro, although they give rise to a greatly reduced number of blast colonies, a measure of hemangioblast potential. Furthermore, normal numbers of hematopoietic progenitors are found in 7.5-day postcoitum flk-1(-/-) embryos, even though 8. 5-day postcoitum flk-1(-/-) embryos are known to be deficient in such cells. Our results suggest that hematopoietic/endothelial progenitors arise independently of Flk-1, but that their subsequent migration and expansion require a Flk-1-mediated signal.

Immunogenicity and relative attenuation of different vaccinia-rabies virus recombinants.

Immunogenicity and relative attenuation were examined for the following Tian Tan strain vaccinia-rabies recombinant viruses: 1) NGc-1, which coexpresses the glycoprotein (G) and nucleocapsid protein (N) of the rabies virus Challenge Virus Standard (CVS) strain; 2) Nc-1, which expresses the CVS N; 3) Gc-2, Gc-3, Gc-4, and Gc-5, which express CVS G via promoters from different vaccinia strains or from different vaccinia genome loci; 4) Ga-1, which expresses the G of rabies virus strain aG; and 5) Gas-1; which expresses the carboxyltruncated G ectodomain (Gs) of strain aG. All but Nc-1 and Gas-1 induced rabies virus neutralizing antibodies (VNAs) and protected groups of mice at very high frequencies from intramuscular (IM) or intracranial (IC) challenge with CVS or SW1 Shanghai dog street rabies virus (SRV); Nc-1 and Gas-1 were partly protective, more frequently against IM challenge. NGc-1 and Gc-5 appeared to induce high levels of VNAs sooner after immunization than the other constructs in mice. Relative attenuation assessed by IM infection of neonatal mice, IC infection of adult mice, and intradermal infection of rabbits with varying doses was best for NGc-1. All the recombinants were at least 100-fold more attenuated than the parent, Tian Tan vaccinia virus. Gc-2, Gc-3, Gc-4, Gc-5, and NGc-1 induced VNAs after immunization of dogs, and a subset of VNA-positive animals vaccinated with NGc-1 or Gc-3 were protected against an otherwise lethal IM injection of SRV at 21 days after vaccination.

Molecular characterization of a chromosome translocation breakpoint t(11;14)(p13;q11) from the cell line KOPT-K1.

Recurrent chromosome translocations involving 11p13 and 14q11 are found in 5-10% of cases of T-ALL. The gene involved in the translocation on chromosome 14 is the T cell antigen receptor alpha or delta. The putative oncogene on chromosome 11 is rhombotin 2 (RBTN2)/translocated in T cell gene 2 (ttg-2), a member of the LIM family of proteins. In this paper we characterize a cell line KOPT-K1 that has a t(11;14)(p13;q11). The breakpoint on chromosome 11 involves an Alu-rich region with the break occurring between two Alu sequences on chromosome 11. In addition, approximately 70 bases from the break on chromosome 11 is a tetranucleotide repeat. Whether either of these structures played a role in the translocation is not known. No heptamer or nonamer sequences, implicated in other rearrangements were found near the breakpoint. The breakpoint on chromosome 11 maps more centromeric than previous translocations of this region. Despite this the RBTN2 gene is highly expressed in KOPT-K1. This cell line will be useful for investigating the role of RBTN2 in leukemogenesis and the mechanism by which the translocation alters the expression of RBTN2.

Influences of Polyactin A on activities of human monocytes in vitro.

Effects of Polyactin A (PAA) on abilities of human monocytes to synthesize and secrete interleukin-1 (IL-1) and to modulate natural killer (NK) cell activity in large granular lymphocytes (LGL) were investigated in vitro. Over a wide range of concentrations (0.01-100 micrograms.ml-1), PAA directly induced IL-1 synthesis and secretion, showing the maximal effect at 10 micrograms.ml-1, and evidently synergized with lipopolysaccharides (LPS) of E coli in stimulation of IL-1 production by human monocytes. The manifestation of PAA pretreated autologous monocytes in modulation of NK cell activity was closely related to PAA concentration. A boosting effect of PAA-treated monocytes on NK activity was observed when PAA 10-100 micrograms.ml-1 were used for pretreatment of monocytes, while an inhibitory influence of monocytes was found when PAA 0.01-0.1 microgram.ml-1 were used. These results demonstrate significant effects of PAA on functions of human monocytes, enhancing IL-1 production and affecting their regulative activity on NK cell cytotoxicity.

Influences of a novel immunopotentiator polyactin A on interleukin 1 production and responsiveness in mice.

Effects of a novel immunopotentiator Polyactin A (PAA), developed in China, on production and responsiveness of murine interleukin 1(IL-1) were investigated. The results demonstrated that: (1) PAA 0.01-100 micrograms.ml-1 directly induced IL-1 synthesis and secretion from murine peritoneal macrophages (PMO) and markedly enhanced IL-1 production of the mouse PMO stimulated by lipopolysaccharides (LPS) of E coli; (2) IL-1 release from the PMO cultured in PAA 0.1 micrograms.ml-1 was detectable as early as 2 h after the incubation, peaked at 24 h, and then decreased gradually; (3) PAA stimulated and enhanced both IL-1 synthesis and release, but its effect on IL-1 release was stronger; (4) PMO from the mice given po PAA 200 mg.kg-1.d-1 for 7 d produced a higher level of IL-1 than those from control group, and the increase in extracellular IL-1 was more significant than that in intracellular one; (5) in vivo, PAA had no effect on IL-1 receptor expression and IL-1 responsiveness of murine lymphocytes, but eliminated the suppressing effects of cyclophosphamide (Cyc) on IL-1 receptor expression and IL-1 responsiveness of mouse lymphocytes. The above findings provide new explanation for action of PAA and new basis for wider clinical applications of PAA.

[Effects of polyactin A on in vitro IL-2 production and responsiveness of human lymphocytes].

The effects of a novel antitumor antibiotic polyactin A (PA) on in vitro IL-2 production and IL-2 responsiveness of human lymphocytes were investigated. The results show that PA in a concentration range from 0.01 to 100 micrograms/ml obviously augmented in vitro IL-2 production, IL-2 receptor expression and responsiveness to IL-2 of human lymphocytes in the presence of PHA, and that these enhancing effects of PA were dose-dependent. The results demonstrated the potentiating effect of PA on cellular immunity and suggested the suitable use of PA in clinical treatment of tumors. The possible application of PA to the treatment of immune disorders involving deficiency of IL-2 production and/or IL-2 responsiveness of lymphocytes is also considered.