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Background: Over the last decade, many advances have been made in laparoscopic techniques in various surgical specialties. The technique of laparoscopic-assisted colectomy (LAC) has been reported since 1992 and has been slowly gaining popularity in the surgical community. Several studies have compared laparoscopic versus open colectomy, assessing its applicability to patients with colon cancer, Crohn's disease, and diverticular disease. Studies to date have assessed length of stay, operative time, and clinical outcome. This study focuses on return of bowel function and length of hospital stay in patients undergoing LAC compared with those undergoing open colectomy., Methods: We performed a retrospective review of patients undergoing either open colon resection or LAC between January 2000 and December 2005. All disease processes and both emergent and elective cases were included. Return of bowel function was determined by passage of flatus or first passage of stool and compared between the 2 groups. The data were statistically analyzed using the Student t test for interval data, and nominal data were analyzed using the chi-square analysis (95% confidence interval; CI)., Results: The study included 247 patients; 179 (72.5%) underwent open colectomy and 68 (27.5%) underwent LAC. Passage of flatus took 3.6 days (95% CI .18 or 3.4 to 3.8) for open colectomy, and 2.9 days (95% CI .19 or 2.7 to 3.1) for LAC. First bowel movement took 4.4 days (95% CI .19 or 4.2 to 4.6) for open colectomy and 3.7 days (95% CI .22 or 3.5 to 3.9) for LAC. When compared between the groups, mean length of hospital stay was 8.01 days (95% CI .93 or 7.1 to 8.9) for open colectomy and 4.38 days (95% CI .38 or 4.0 to 4.8) for LAC., Conclusion: Both return of bowel function and length of stay were statistically significantly shorter in LAC compared with those in open colectomy, which may indicate faster recovery after bowel surgery in patients undergoing the laparoscopic approach.

Wnt signaling regulates a variety of developmental processes in animals. Although the beta-catenin-dependent (canonical) pathway is known to control cell fate, a similar role for noncanonical Wnt signaling has not been established in mammals. Moreover, the intracellular cascades for noncanonical Wnt signaling remain to be elucidated. Here, we delineate a pathway in which Wnt3a signals through the Galpha(q/11) subunits of G proteins to activate phosphatidylinositol signaling and PKCdelta in the murine ST2 cells. Galpha(q/11)-PKCdelta signaling is required for Wnt3a-induced osteoblastogenesis in these cells, and PKCdelta homozygous mutant mice exhibit a deficit in embryonic bone formation. Furthermore, Wnt7b, expressed by osteogenic cells in vivo, induces osteoblast differentiation in vitro via the PKCdelta-mediated pathway; ablation of Wnt7b in skeletal progenitors results in less bone in the mouse embryo. Together, these results reveal a Wnt-dependent osteogenic mechanism, and they provide a potential target pathway for designing therapeutics to promote bone formation.

Plants are susceptible to infection by a broad range of fungal pathogens. Many horticulturally important crop species lack adequate genetic resistance to disease. Studies on potential mechanisms of disease resistance in plants have revealed the importance of a range of pathogenesis-related (PR) proteins with antifungal activity in reducing colonization of plant tissues by pathogens. We are evaluating a range of PR-proteins, through heterologous expression in transgenic carrot tissues, for their effects on fungal disease development. The protocols for carrot transformation with a thaumatin-like protein are described. In addition, the use of herbicide resistance as a selectable marker in carrot transformation is illustrated. In this protocol, petiole segments from carrot seedlings are exposed to Agrobacterium for 10-30 min and co-cultivated for 3 d, after which herbicide selection is imposed until embryogenic calli are produced after 8-12 wk. The transfer of the embryogenic calli to hormone-free medium yields transgenic plantlets. This genetic transformation protocol has supported the generation of transgenic carrot plants with defined T-DNA inserts at the rate of between 1 and 3 Southern positive independent events out of 100.

Synthesis and studies of poly(alkyl aryl ether) dendrimers, possessing carboxylic acid functionalities at their peripheries, are reported. 5-Bromopentyloxy methylisophthalate was utilized as the monomer to O-alkylate the phenolic hydroxyl groups of poly(alkyl aryl ether) dendrimers. Dendrimers of first, second, and third generations, possessing 6, 12, and 24 carboxylic acids, respectively, were thus prepared. These dendrimers were soluble in alkaline aqueous solutions, and the ensuing microenvironmental properties of the aqueous solutions were assessed by pyrene solubilization studies. Upon establishing the presence of nonpolar microenvironments within the dendritic structures, solubilizations of few organic substrates were conducted and their photochemical behaviors were assessed. Specifically, the photolysis of 1-phenyl-3-p-tolyl-propan-2-one and benzoin ethyl ether and photodimerization of acenaphthylene were conducted. These studies revealed that the product distribution and the "cage effect" were more distinct and efficient for the third generation dendrimer, than for the first and second generation dendrimers. The photochemical studies of carboxylic acid functionalized dendrimers were compared to that of hydroxyl group terminated poly(alkyl aryl ether) dendrimers.

Several recent reports claim the generation of insulin-producing cells from embryonic stem cells via the differentiation of progenitors that express nestin. Here, we investigate further the properties of these insulin-containing cells. We find that although differentiated cells contain immunoreactive insulin, they do not contain proinsulin-derived C-peptide. Furthermore, we find variable insulin release from these cells upon glucose addition, but C-peptide release is never detected. In addition, many of the insulin-immunoreactive cells are undergoing apoptosis or necrosis. We further show that cells cultured in the presence of a phosphoinositide 3-kinase inhibitor, which previously was reported to facilitate the differentiation of insulin(+) cells, are not C-peptide immunoreactive but take up fluorescein isothiocyanate-labeled insulin from the culture medium. Together, these data suggest that nestin(+) progenitor cells give rise to a population of cells that contain insulin, not as a result of biosynthesis but from the uptake of exogenous insulin. We conclude that C-peptide biosynthesis and secretion should be demonstrated to claim insulin production from embryonic stem cell progeny.

Water-soluble poly(alkyl aryl ether) dendrimers have been explored for their use as hosts of organic substrates in aqueous media. Prototypical photoreactions, namely, photo-Fries reaction of (a) 1-naphthyl benzoate and (b) 1-naphthyl phenyl ester and alpha-cleavage reaction of (a) dibenzyl ketones and (b) benzoin alkyl ethers, have been examined. We find that a dendritic microenvironment not only restricts the mobility of radical intermediates but also rigidly encapsulates the substrate, intermediates, and products from "leaking" to the bulk environment. Comparative studies of the same photoreactions in micellar media demonstrate that dendritic media offer much better constrainment than the micelles.

Azospirillum is used extensively in rice and other cereal crops as a biofertilizer. There is a substantial opportunity to improve the efficiency of this bacterium through the transfer of genes of agricultural importance from other organisms. Chitinases are antifungal proteins, and expression of chitinase genes in Azospirillum would help to develop strains with potential antifungal activities. So far there are no reports about transfer of plant genes into Azospirillum and their expression. The present study was aimed at expressing an antifungal gene (a rice chitinase) of plant origin in Azospirillum brasilense. A rice chitinase cDNA (RC 7) that codes for a 35 kDa protein was subcloned into a broad host range plasmid pDSK519 under the control of LacZ promoter. The plasmid was mobilized into the nitrogen-fixing bacterium, Azospirillum brasilense strain SP51eFL1, through biparental mating. The conjugation frequency was in the range of 35-40 x 10(-6). The transconjugants grew in nitrogen-free media and fixed gaseous nitrogen in vitro. However, their growth and nitrogen-fixing ability were slightly less than those of the wild-type. Expression of the protein was demonstrated through western blotting of the total cell protein, which detected a 35 kDa band that was immuno-reactive to a barley chitinase antibody. The cell lysates also hydrolyzed various chitin substrates, which resulted in release of free sugars demonstrating the chitinase activity of transconjugants. The expressed protein also had antifungal activity as demonstrated by inhibition of growth of the plant pathogenic fungus, Rhizoctonia solani.

A series of azobenzene-functionalized poly(alkyl aryl ether) dendrimers have been synthesized and their photochemical and photophysical properties in solution and as thin films have been investigated. Although the photochemical behavior of the azodendrimers in solution indicated that the azobenzene units behave independently, very similar to the constituent monomer azobenzene unit, the properties of thin solid films of the dendrimers were distinctly different. The azodendrimers, AzoG1, AzoG2, and AzoG3 were observed to form stable supercooled glasses, which showed long-wavelength absorption and red emission characteristics of J-aggregates of the azobenzene chromophores. Reversible photoinduced isomerization of the azodendrimers in the glassy state is described.

Chloroethenes like tetrachloroethene (PCE) are the most prevalent groundwater contaminants in the USA. Their presence as nonaqueous phase liquids (NAPLs) makes remediation difficult. Among options for NAPL cleanup, co-solvent injection has demonstrated success. However, the process has the potential to leave considerable residue of the co-solvent as well as residual chloroethene. Our rationale in this study was to examine whether this residual solvent could be a potential electron donor for the remediation of the residual chloroethene. We hypothesized that ethyl lactate, a "green" solvent, could serve both as a NAPL extraction solvent and an electron donor for reductive dechlorination of residual chloroethene. We examined whether a mixed culture known to degrade PCE with lactate could also grow on ethyl lactate and whether it could stimulate PCE dechlorination. Biomass growth and PCE dechlorination were observed by protein and chloride production, respectively, in the culture; with a specific dechlorination rate of 50 150 microg (mg cell d)(-1). Ethyl lactate abiotically breaks down to ethanol and lactate, the latter being a rich source of hydrogen fo reductive dechlorination. The results demonstrate that ethyl lactate may be promising for in situ bioremediation following NAPL extraction.

Poly(alkyl aryl ether) dendrimers of up to four generations composed of a phloroglucinol core, branching components, and pentamethylene spacers are synthesized by a divergent growth methodology. A repetitive synthetic sequence of phenolic O-alkylation and O-benzyl deprotection reactions are adopted for the synthesis of these dendrimers. The peripheries of the dendrimers contain 6, 12, 24, and 48 phenolic hydroxyl groups, either in the protected or unprotected form, for the first, second, third, and fourth generations, respectively. Because of the presence of hydrophilic exterior and relatively hydrophobic interior regions, alkaline aqueous solutions of these dendrimers are able to solubilize an otherwise insoluble pyrene molecule and these supramolecular complexes precipitate upon neutralization of the aqueous solutions.

Research on antifungal proteins and other mechanisms that provide the biochemical basis for host-plant resistance to stalk rot and grain molds is reviewed in this paper. Stalk rot caused by Fusarium species leads to substantial yield loss due to poor grain filling and/or lodging. A transgenic sorghum expressing high levels of chitinase exhibited less stalk rot development when exposed to conidia of F. thapsinum. Grain mold of sorghum is associated with warm humid environments and results from colonization by several fungi (F. thapsinum, Curvularia lunata, and Alternaria alternata) of the developing caryopsis. The roles of several biochemical mechanisms (tannins, phenolic compounds, red pericarp, proteins, hard endosperm, and antifungal proteins) on grain mold resistance are discussed. Resistance mechanisms related to these compounds appear to be additive, and pyramiding of genes is a feasible approach to limit grain deterioration. Several experimental approaches are proposed to extend current findings.

Infantile digital fibromatosis (IDF) is a form of fibromatosis usually restricted to childhood. Typically occuring on fingers and toes of children and rarely in the oral cavity [Canioni et al. Pathol. Res. Pract. 187 (1991) 886] and in adults [Viale et al. Histopathology 12 (1998) 415]. It was first described by Reye [Arch. Pathol. Lab. Med. 80 (1965) 228]. IDF (Reyes tumour) is a rarely encountered, non malignant tumour of children. The lesions may be multiple and are either present at birth or appear during the first 2 years of life and are prone for recurrence after removal. Recognition is important as they often regress spontaneously if left alone [Ishi et al. Br. J. Dermatol. 121 (1989) 129]. We report here a care of IDF on right second toe, which was congenital in origin and was clinically similar to keloid.