Photodynamic therapy provides local control of cholangiocarcinoma in patients awaiting liver transplantation.

Many transplant centers use endoscopically directed brachytherapy to provide locoregional control in patients with otherwise incurable cholangiocarcinoma (CCA) who are awaiting liver transplantation (LT). The use of endoscopic retrograde cholangiopancreatography (ERCP)-directed photodynamic therapy (PDT) as an alternative to brachytherapy for providing locoregional control in this patient population has not been studied. The aim of this study was to report on our initial experience using ERCP-directed PDT to provide local control in patients with unresectable CCA who were awaiting LT. Patients with unresectable CCA who underwent protocol-driven neoadjuvant chemoradiation and ERCP-directed PDT with the intent of undergoing LT were reviewed. Four patients with confirmed or suspected CCA met the inclusion criteria for protocol LT. All four patients (100%) successfully underwent ERCP-directed PDT. All patients had chemoradiation dose delays, and two patients had recurrent cholangitis despite PDT. None of these patients had progressive locoregional disease or distant metastasis following PDT. All four patients (100%) underwent LT. Intention-to-treat disease-free survival was 75% at mean follow-up of 28.1 months. In summary, ERCP-directed PDT is a reasonably well tolerated and safe procedure that may have benefit by maintaining locoregional tumor control in patients with CCA who are awaiting LT.

Human RhoA/RhoGDI complex expressed in yeast: GTP exchange is sufficient for translocation of RhoA to liposomes.

The human small GTPase, RhoA, expressed in Saccharomyces cerevisiae is post-translationally processed and, when co-expressed with its cytosolic inhibitory protein, RhoGDI, spontaneously forms a heterodimer in vivo. The RhoA/RhoGDI complex, purified to greater than 98% at high yield from the yeast cytosolic fraction, could be stoichiometrically ADP-ribosylated by Clostridium botulinum C3 exoenzyme, contained stoichiometric GDP, and could be nucleotide exchanged fully with [3H]GDP or partially with GTP in the presence of submicromolar Mg2+. The GTP-RhoA/RhoGDI complex hydrolyzed GTP with a rate constant of 4.5 X 10(-5) s(-1), considerably slower than free RhoA. Hydrolysis followed pseudo-first-order kinetics indicating that the RhoA hydrolyzing GTP was RhoGDI associated. The constitutively active G14V-RhoA mutant expressed as a complex with RhoGDI and purified without added nucleotide also bound stoichiometric guanine nucleotide: 95% contained GDP and 5% GTP. Microinjection of the GTP-bound G14V-RhoA/RhoGDI complex (but not the GDP form) into serum-starved Swiss 3T3 cells elicited formation of stress fibers and focal adhesions. In vitro, GTP-bound-RhoA spontaneously translocated from its complex with RhoGDI to liposomes, whereas GDP-RhoA did not. These results show that GTP-triggered translocation of RhoA from RhoGDI to a membrane, where it carries out its signaling function, is an intrinsic property of the RhoA/RhoGDI complex that does not require other protein factors or membrane receptors.

Preirradiation PSA predicts biochemical disease-free survival in patients treated with postprostatectomy external beam irradiation.

PURPOSE: To assess the clinical outcome and prostate-specific antigen (PSA) response and to determine prognostic factors for biochemical disease-free survival in patients treated with external beam radiotherapy following radical prostatectomy without hormonal therapy. METHODS AND MATERIALS: Forty-eight patients were treated after prostatectomy with radiotherapy between March, 1988 and December, 1993. Seven patients had undetectable PSA (<0.2) and the remainder had detectable PSA at the time of irradiation (overall: median 2.7, range 0-24.9). Nine patients had biopsy proven local recurrence, palpable local disease, or positive preirradiation imaging. No patients received hormonal therapy prior to irradiation. Median follow-up was 55 months. A median dose of 60 Gy (range 58-66) was given to the prostate bed. Survival was analyzed using the life-table method. Actuarial biochemical disease-free survival was the primary endpoint studied. RESULTS: In patients with detectable PSA, 51% had levels return to undetectable after irradiation. The actuarial 5-year freedom from biochemical failure for all patients was 24%. A significant difference in biochemical disease-free survival was seen for patients irradiated with preirradiation PSA that was undetectable (p < 0.001), or preirradiation PSA that was < or =2.7 (p = 0.002), vs. preirradiation PSA that was >2.7. Five-year actuarial biochemical disease-free survival values were 71, 48, and 0%, respectively, for the three groups. Biochemical disease-free survival was not affected by preoperative PSA level, clinical stage, Gleason's score, pathologic stage, surgical margins, presence of undetectable PSA after surgery, surgery to radiation interval, total dose, or presence of clinically suspicious local disease. Based on digital rectal exam, there were no local failures. CONCLUSION: Biochemical disease-free survival after postprostatectomy radiation is predicted by the PSA at the time of irradiation. Clinical local control is excellent, but distant failure remains a significant problem in this population. The addition of concomitant systemic therapy should be investigated in patients with PSA >2.7.

MR grid-tagging using hyperpolarized helium-3 for regional quantitative assessment of pulmonary biomechanics and ventilation.

A new technique is demonstrated in six healthy human subjects that combines grid-tagging and hyperpolarized helium-3 MRI to assess regional lung biomechanical function and quantitative ventilation. 2D grid-tagging, achieved by applying sinc-modulated RF-pulse trains along the frequency- and phase-encoding directions, was followed by a multislice fast low-angle shot (FLASH)-based acquisition at inspiration and expiration. The displacement vectors, first and second principal strains, and quantitative ventilation were computed, and mean values were calculated for the upper, middle, and lower lung regions. Displacements in the lower region were significantly greater than those in either the middle or upper region (P < 0.005), while there were no significant differences between the three regions for the two principal strains and quantitative ventilation (P = 0.11-0.92). Variations in principal strains and ventilation were greater between subjects than between lung zones within individual subjects. This technique has the potential to provide insight into regional biomechanical alterations of lung function in a variety of lung diseases.

Lipopolysaccharide releases a priming substance from platelets that augments the oxidative response of polymorphonuclear neutrophils to chemotactic peptide.

Human neutrophils produce small amounts of O2- when stimulated with the chemotactic peptide F-Met-Leu-Phe; preincubating neutrophils with low concentrations of lipopolysaccharide (LPS) markedly increases this response, an effect referred to as priming. Neutrophil suspensions without mononuclear cells and platelets were insusceptible to priming by 10 ng of LPS; susceptibility was restored by reintroducing platelets, approximately five platelets per neutrophil. Incubation of platelets with 10 ng of LPS/mL released a soluble factor that produced graded priming responses of at least fivefold in neutrophils. The priming factor had the properties of a labile protein and did not resemble previously described mediators derived from platelets. Anthrax toxin, which inhibits priming of neutrophils by LPS, inhibited priming by the platelet factor but not release of the factor from platelets. Thus, the platelet factor mediates a portion of the overall priming effect of LPS and thereby modulates the level of O2- generation by neutrophils.

Dental study in patients with rheumatoid arthritis.

Twenty-one patients with rheumatoid arthritis took part in a comparison of three toothbrushes, each used for one month in a randomized trial. The three toothbrushes were a conventional toothbrush with modified handle to allow ease of gripping, an electric toothbrush, and thirdly a finger-stall attached to a normal toothbrush. There was no change in the patients' rheumatoid status during the trial. The patients were scored for plaque and gingival changes but no difference was found between the three toothbrushes. We recommend a standard toothbrush with a modified grip for the rheumatoid hand; the extra expense of an electric toothbrush cannot be justified.

Coaggregation of paramagnetic d- and f-block metal ions with a podand-framework amine phenol ligand.

This report covers initial studies in the coaggregation of nickel (Ni2+) and lanthanide (Ln3+) metal ions to form complexes with interesting structural and magnetic properties. The tripodal amine phenol ligand H3tam (1,1,1-tris(((2-hydroxybenzyl)amino)methyl)ethane) is shown to be particularly accommodating with respect to the geometric constraints of both transition and lanthanide metal ions, forming isolable complexes with both of these ion types. In the solid-state structure of [Ni(H2tam)(CH3CN)]PF6.2.5CH3CN.0.5CH3OH (1), the Ni(II) center has a distorted octahedral geometry, with an N3O2 donor set from the [H2tam]- ligand and a coordinated solvent (acetonitrile) occupying the sixth site. The reaction of stoichiometric amounts of H3tam with the Ni(II) ion in the presence of lanthanide(III) ions provides [LnNi2(tam)2]+ cationic complexes which contain coaggregated metal ions. These complexes are isolable and have been characterized by a variety of analytical techniques, with mass spectrometry proving to be particularly diagnostic. The solid-state structures of [LaNi2(tam)2(CH3OH)1/2(CH3CH2OH)1/2(H2O)]ClO4.0.5CH3OH.0.5CH3CH2OH.4H2O (2), [DyNi2(tam)2(CH3OH)(H2O)]ClO4.CH3OH. H2O(6), and [YbNi2(tam)2(H2O)]ClO4.2.58H2O(9) have been determined. Each complex contains two octahedral Ni(II) ions, each of which is encapsulated by the ligand tam3- in an N3O3 coordination sphere; each [Ni(tam)]-unit caps the lanthanide(III) ion via bridging phenoxy oxygen donor atoms. In 2, La3+ is eight-coordinated, while in 6, Dy(III) is seven- (to "weakly eight-") coordinated, and Yb(III) in 9 has a six-coordination environment. The complexes are symmetrically different, 2 possessing C2 symmetry and 6 and 9 having C1 symmetry. Magnetic studies of 2, 6, and 9 indicate that antiferromagnetic exchange coupling between the Ni(II) and Ln(III) ions increases with decreasing ionic radius of Ln(III).