Expression patterns of costimulatory molecules on cells derived from human hematological malignancies

In order to elucidate the possibility of costimulatory molecules-mediated immuno or immuno-gene therapy for human hematological malignancies, we analyzed 30 hematopoietic cell lines and cells obtained from 48 patients with hematological malignancies for the expression of costimulatory molecules such as CD80 and CD86. The 30 hematopoietic cell lines were composed of 4 cell lines derived from the patients with T-cell acute lymphoblastic leukemia (T-ALL), 3 from Philadelphia chromosome positive ALL (Ph1+ALL), 8 from acute myeloblastic leukemia (AML), 3 from acute promyelocytic leukemia (APL), 8 from chronic myeloid leukemia at blast crisis (CML-BC), 3 from Burkitt's lymphoma and one from follicular cell lymphoma. The expression of CD80 or CD86 was frequent on cell lines derived from the patients with CML-BC or Burkitt's lymphoma, while it was rare on cell lines from T-ALL. Subsequently we analyzed the cells obtained from 48 patients with hematological malignancies, which consisted of 6 samples from patients with ALL, 30 from AML, 2 from CML-BC, 3 from B-cell lymphoma and one from each acute mixed leukemia (AMixL), adult T cell leukemia (ATL), T-cell large granular lymphocytic leukemia (T-LGL leukemia), chronic lymphocytic leukemia (CLL), myelodysplastic syndrome (MDS)-RAEB in T, multiple myeloma (MM) or T-cell lymphoma. Among all the 48 cases, all cases except one case with CLL and two with B cell lymphoma were demonstrated to be negative for CD80 on the neoplastic cells. CD86 and HLA-DR were shown to be expressed in 50% and 88% of total 48 cases respectively. In 30 AML samples, CD86 was positive in 15 cases (50%), which was sharply in contrast with the finding that CD80 was not detected in any AML samples. HLA-DR was expressed in 25 AML samples (83%). We also treated seven human hematopoietic cell lines with IFN-gamma, IL-12 or IL-15 and observed whether these cytokines could induce or enhance the expression of CD40, CD54, CD58 and HLA-DR as well as CD80 and CD86. The present study demonstrated that the expression of CD86 could be upregulated not only by IFN-gamma, but also by IL-12 or IL-15 in some cell lines. These findings suggested the possibility that the absence of CD80 on neoplastic cells may be associated with the lack of efficient anti-tumor immunity in most patients with hematological malignancies and that the immuno or immuno-gene therapy manipulating the expression of costimulatory molecules such as CD80 may be a useful treatment modality for hematological malignancies.

[Morphologic changes of hippocampal neurons irradiated with gamma knife]

OBJECTIVE

To study the early radiobiological response of Gamma knife to the cultured hippocampal neurons in vitro.

METHODS

The light and electron microscopy were used to see the Gamma knife irradiated neurons of rat.

RESULTS

Degenerated neurons showed swelling and refrangibility weakening or disappearance of soma, pellet-like changes of cytoplasm, thickening and breaking of processes under phase-contrast inverted microscopy. Lesions with swelling of soma and fold vanish on cell surface, enlargement of volume and rapture of membrane, the sparse of network among the cells, thickening and breaking of processes were observated under scanning electron microscopy. The ultrastructure of the insulted neurons showed irregular nuclei and concavity of nucleus membrane, a lot of swelling or condensation of mitochondria, separation of ribosome and neurofilament, and vacuolated changes of cytoplasm.

CONCLUSIONS

The effect on Gamma knife irradiated neurons is similar to that of normal brain tissues. There is a dose-response relationship at early stage. The study indicates that low-dose irradiation can cause damage to cells.

[Analysis of the properties of plasma produced by pulsed laser ablation of metal Al at different ambient pressures]

A time and space resolved diagnostic technique was used to study the properties of plasma produced by a pulsed laser on an Al target irradiated at different ambient pressures. The velocities of projected particles were measured. The projected ranges for 1-10keV AI2+ ions ejecting into ambient gas at different pressures were calculated in theory. The calculated results can explain the observed experimental phenomena successfully.

Alteration of limb and brain patterning in early mouse embryos by ultrasound-guided injection of Shh-expressing cells

A basic limitation of the study of development in the mouse is the inaccessibility of the embryos, which are encased in the maternal uterus. We demonstrate the first use of ultrasound backscatter microscopy for guiding injections of cells and other agents into early stage mouse embryos. Cells were injected into the mouse neural tube cavity as early as 9.5 days post coitus (E9.5), and into the developing limb buds as early as E10.5. Furthermore, a cell-line engineered to express the secreted factor Sonic Hedgehog (Shh) was injected into early developing mouse brains or limbs. The Shh-expressing cells were found to induce ectopic expression of the Shh target genes Patched and Hnf3beta in the dorsal brain, and to alter digit patterning in the anterior limb bud. These results show that gene misexpression studies can be performed in mouse embryos using ultrasound-guided injection of transfected cells or retroviruses. In combination with the many available mouse mutants, this method offers a new approach for analyzing genetic interactions through gain-of-function studies performed in mutant mouse backgrounds.

New paramagnetic species formed at the expense of the transient tyrosyl radical in mutant protein R2 F208Y of Escherichia coli ribonucleotide reductase

The highly conserved residue F208 in protein R2 of E. coli ribonucleotide reductase is close to the binuclear iron center, and found to be involved in stabilizing the tyrosyl radical Y122. in wild type R2. Upon the reconstitution reaction of the mutant R2 F208Y with ferrous iron and molecular oxygen, we observed a new EPR singlet signal (g = 2.003) formed concomitantly with decay of the transient tyrosyl radical Y122. (g = 2.005). This new paramagnetic species (denoted Z) was stable for weeks at 4 degrees C and visible by EPR only below 50 K. The EPR singlet could not be saturated by available microwave power, suggesting that Z may be a mainly metal centered species. The maximum amount of the compound Z in the protein purified from cells grown in rich medium was about 0.18 unpaired spin/R2. An identical EPR signal of Z was found also in the double mutant R2 F208Y/Y122F. In the presence of high concentration of sodium ascorbate, the amounts of both the transient Y122. and the new species Z increased considerably in the reconstitution reaction. The results suggest that Z is most likely an oxo-ferryl species possibly in equilibrium with a Y208 ligand radical.

Monte Carlo-assisted voxel source kernel method (MAVSK) for internal beta dosimetry

A method is described for the determination of patient-specific organ beta doses given a known cumulated internal radioactivity distribution. A voxel source kernel for 90Y analogous to the point source function was simulated. Dose to each organ of interest could then be estimated by convolving the voxel source kernel with the patient's 3-D volume with known radioactivity assigned to each voxel. The dose calculation on eight organs took less than 1 min per patient using a Sun Sparc10 workstation.

Simultaneous HLA Class I and Class II antibodies screening with flow cytometry

A flow cytometric method of simultaneously screening both HLA Class I and Class II panel reactive antibodies (PRA) was developed using a pool of 30 different Class I and 30 different Class II microbeads coated with purified HLA antigens. The antibodies in the serum that react specifically to the coated HLA antigens are detected by using a FITC-conjugated antibody against human IgG. Percent PRA can be determined by the percentage of microbeads that react positively to the serum. There is no cross-reactivity between the Class I and Class II microbeads. A mixture of Class I and Class II microbeads can be distinguished by their different fluorescent properties on the flow cytometry analysis. Thus, both Class I and Class II PRA can be detected from a single tube reaction.

[Treatment of old femoral neck fracture with implantation of a vascularized fibular graft]

OBJECTIVE

To investigate the healing of old femoral neck fracture treated with transplantation of vascularized fibula graft accompanied with lag screw, and rehabilitation of and precaution against ischemic necrosis of femoral head.

METHOD

Vascularized fibula autograft was transplanted to the anterolateral side of the femoral neck with an internal fixator of lag screw. Fibular artery and vein were anastomosed with lateral circumflex artery and vein.

RESULT

186 of 229 cases subjected to systemic X-ray films and function follow-up (3 to 15 years). The percentage of fracture healing was 93.0% the sulass rate 86.5%.

CONCLUSION

Fibula with blood supply and compressed screw have a combined fixation effect of the old femoral neck fracture. Fibula is solid enough for supporting the femoral head and preventing it from collapse. Vascularized fibular grafting provides blood supply to the affected femoral head and neck, promoting femoral head restoration and reconstruction.

Pulmonary embolus in pregnant patients: survey of ventilation-perfusion imaging policies and practices

PURPOSE

To assess the policies and practices of nuclear medicine facilities as regards ventilation-perfusion (V-P) imaging in pregnant patients suspected of having pulmonary embolus.

MATERIALS AND METHODS

Surveys were mailed to physician-directors of 1,000 randomly selected facilities at which nuclear imaging studies are performed. Information gathered included use of V-P imaging in pregnant patients, written policies, informed consent procedures, and modifications of standard protocols.

RESULTS

Of the 1,000 surveys mailed, 327 (33%) completed surveys were returned. Of these 327 respondents, 220 (67%) reported that they perform V-P imaging in pregnant patients suspected of having pulmonary embolus. Of these 220 respondents, 115 (52%) routinely obtain informed consent, and 170 (77%) modify their standard V-P imaging protocol for pregnant patients. The most common modification (135 [79%] of 170 respondents) was reduction of the perfusion agent dose. Reported practice patterns for written policies, informed consent, and modifications did not show statistically significant trends among respondents in varying practice settings or geographic locations.

CONCLUSION

Most respondents perform V-P imaging in pregnant patients suspected of having pulmonary embolus, with considerable variability in their policies and practices.

TGF-beta type II receptor in rat renal vascular development: localization to juxtaglomerular cells

To further define the role of transforming growth factor-beta (TGF-beta) receptors in renal vascular development, detailed immunohistochemical studies of TGF-beta receptor expression were performed from gestational day 15 through adulthood. On gestational day 15, TGF-beta type II receptor immunoreactivity was restricted to perirenal stromal and vascular cells. On gestational day 17 TGF-beta type II receptor immunoreactive stromal cells were observed within the kidney, with the same distribution as stromal alpha-smooth muscle actin and renin immunoreactive cells, and intense stromal TGF-beta type II receptor immunoreactivity continued through postnatal day 5. As vascular development progressed, TGF-beta type II receptor, alpha-smooth muscle actin and renin immunoreactivity became progressively restricted to small renal arteries and arterioles. Expression of TGF-beta type II receptors and renin was very intense in afferent glomerular arterioles during postnatal days 5 to 15, and then became progressively restricted only to juxtaglomerular cells in the mature kidney. TGF-beta type I receptor (ALK-5, ALK-1 and ALK-2) immunoreactivity was not detected in stromal or vascular elements during development or in the mature kidney. Intense TGF-beta type II receptor expression in renal stromal vascular smooth muscle cell precursors and developing blood vessels suggests a role for the TGF-beta type II receptors in the formation of the renal vascular smooth muscle compartment. The continued intense expression in juxtaglomerular cells argues for a role in renin synthesis and/or release. The absence of ALK-5, ALK-1, and ALK-2 in developing vascular smooth muscle and mature juxtaglomerular cells indicates that the canonical view of TGF-beta signaling may not hold in these locations.

Changes in mechanical strength of intramuscular connective tissue during postmortem aging of beef

We studied changes in mechanical strength during postmortem aging of bovine semitendinosus muscle using intramuscular connective tissue (IMCT) preparations from muscle stored at 4 degrees C. In the preparation, muscle fiber elements were removed, leaving a virtually intact structure of the endomysium and perimysium. The shear-force value of the IMCT preparation remained unchanged up to 10 d postmortem and decreased linearly thereafter. The yield of the perimysial fraction, which was measured as an indicator of mechanical properties of the perimysium, remained almost unchanged up to 14 d postmortem, and decreased gradually thereafter. These results suggest that the mechanical strength of the intramuscular connective tissue changes slowly during postmortem aging of beef; it remains almost unchanged for up to 10 d postmortem and progressively decreases thereafter. Thus, intramuscular connective tissue seems to affect beef tenderization in extended aging.

Quantitative structure-activity relationships on 5-substituted terbenzimidazoles as topoisomerase I poisons and antitumor agents

Several 5-substituted terbenzimidazoles were synthesized and evaluated as mammalian topoisomerase I poisons and for cytotoxicity against a human lymphoblastoma cell line, RPMI-8402. No correlation was observed between topoisomerase I poisoning activity and the Hansch pi value or the sigma meta and sigma para values associated with each substituent. These data suggest that electronic effects and relative lipophilicity of substituents at the 5-position of these terbenzimidazoles do not have a significant effect upon intrinsic topoisomerase I poisoning activity. There was, however, a good correlation between the relative pi values for the various substituents evaluated and cytotoxic activity. Experimentally determined log P values did not correlate well with either cytotoxicity or pi values. Capacity factors (log k') as determined by high pressure liquid chromatography did correlate well with the pi values of varied substituents and cytotoxicity. These data indicate that the relative lipophilic activity of substituents at the 5-position of these terbenzimidazoles can strongly influence relative cytotoxic activity.

Induction of allograft nonresponsiveness after intrathymic inoculation with donor class I allopeptides. II. Evidence for persistent chronic rejection despite high levels of donor microchimerism

We have recently demonstrated that three synthetic peptides corresponding to the donor class I RT1.Aa molecule induce long-term survival of cardiac allografts in the PVG.R8-to-PVG.1U rat strain combination (disparate for one isolated class I, RT1.A, molecule) when presented to the recipient immune system in the thymus. Long-term graft survivors had measurable levels of donor-reactive alloantibodies in their serum. In this study, we examined long-term allografts for the presence of chronic rejection and donor microchimerism to assess whether this regimen of immune modulation establishes true tolerance and whether this tolerance is dependent upon the presence of donor-recipient microchimerism. Histological examination of long-term heart grafts (>100 days) demonstrated chronic rejection, including a mild degree of myocardial infiltration by mononuclear cells, mild to moderate myocardial fibrosis, and various vascular changes ranging from focal intimal thickening to total vascular lumen blockade due to smooth muscle cell proliferation. In contrast, long-term syngeneic hearts transplanted under similar experimental conditions lacked these pathological manifestations. Donor microchimerism was analyzed using the polymerase chain reaction with a pair of oligonucleotides specific for the donor class I RT1.Aa gene and genomic DNA harvested from various tissues from graft recipients. We detected high levels of donor microchimerism in the heart, kidney, liver, skin, bone marrow, thymus, and lymph nodes of long-term graft recipients. Donor microchimerism was also detected in unmanipulated control graft recipients at rejection (7 days) and in intrathymically manipulated recipients that rejected allografts in a delayed fashion (12-82 days). These data clearly demonstrate that intrathymic inoculation of donor class I allopeptides induces long-term graft survival but does not prevent chronic rejection. Allograft rejection occurred despite high levels of donor microchimerism, providing direct evidence that donor-recipient microchimerism is not sufficient for the prevention of acute or chronic rejection in this model.

Estimating residence times and their associated errors in patient absorbed-dose calculation

OBJECTIVE

An approach for estimating organ residence times (tau) and their errors in patient internal emitter radiation dosage calculations has been determined.

METHODS

Using a modeling algorithm and its associated parameters, chimeric anti-CEA monoclonal antibody (cT84.66) patient organ uptake data and residence times of source organ activity were calculated. Through the covariance matrix of the model's parameters and subsequent Monte Carlo simulations, errors in organ residence time (gamma tau) also were estimated

RESULTS

These relative tau errors were found to be model-dependent; increasing as the number of organs being simultaneously modeled in a set of two patients being considered for 90Y-cT84.66 radioimmunotherapy.

CONCLUSION

Use of modeling and Monte Carlo methods provide a general, direct procedure for calculating the degree of accuracy of activity integrals and other mathematical functions of kinetic variables.

Pharmacokinetic modeling and absorbed dose estimation for chimeric anti-CEA antibody in humans

The objective of this article was to model pharmacokinetic data from clinical diagnostic studies involving the 111In-labeled monoclonal antibody (MAb) chimeric T84.66, against carcinoembryonic antigen. Model-derived results based on the 111In-MAb blood, urine and digital imaging data were used to predict 90Y-MAb absorbed radiation doses and to guide treatment planning for future therapy trials. Fifteen patients with at least one carcinoembryonic antigen-positive lesion were evaluated. We report the kinetic parameter estimates and absorbed 111In-MAb dose and projected 90Y-MAb doses for each patient as well as describe our approach and rationale for modeling an extensive set of pharmacokinetic data.

METHODS

The ADAPT II software package was used to create three- and five-compartment models of uptake against time in the patient population. The "best-fit" model was identified using ordinary least squares. Areas under the curve were calculated using the modeled curves and input into MIRDOSE3 to estimate absorbed radiation doses for each patient.

RESULTS

A five-compartment model best described the liver, whole body, blood and urine data for a subcohort of nine patients with digital imaging data. A three-compartment model best described the blood and urine data for all 15 clinical patients accrued in the clinical trial. For the subcohort, the largest projected 90Y-MAb doses were delivered to the liver (mean, 24.78 rad/mCi; range, 15.02-37.07 rad/mCi), with red marrow estimates on the order of 3.32 rad/mCi (range, 1.24-5.55) of 90Y. Corresponding estimates for the 111In-MAb were 3.18 (range, 2.09-4.43) and 0.55 (range, 0.34-0.74), respectively.

CONCLUSION

The three- and five-compartment models presented here were successfully used to represent the blood, urine and imaging data. This was evidenced by the small standard errors for the kinetic parameter estimates and R2 values close to 1. As planned future therapeutic trials will involve stem cell support to alleviate hematological toxicities, the development of an approach for estimating doses to other major organs is crucial.

Clinical evaluation of indium-111-labeled chimeric anti-CEA monoclonal antibody

Chimeric T84.66 (cT84.66) is a high-affinity (1.16 x 10[11] M[-1]) IgG1 monoclonal antibody (MAb) against carcinoembryonic antigen (CEA). This pilot trial evaluated the tumor-targeting properties, biodistribution, pharmacokinetics and immunogenicity of 111In-labeled cT84.66.

METHODS

Patients with CEA-producing metastatic malignancies were administered a single intravenous dose of 5 mCi 111In-diethylenetriaminepentaacetic acid-cT84.66. Serial blood samples, 24-hr urine collections and nuclear images were collected up to 7 days postinfusion. Human antichimeric antibody response was assessed up to 6 mo postinfusion.

RESULTS

Imaging of at least one known tumor site was observed in 14 of 15 (93%) patients. Seventy-four lesions were analyzed with an imaging sensitivity rate of 45.1% and a positive predictive value of 94.1%. In one patient, two additional bone metastases developed within 6 mo of antibody administration at sites initially felt to be falsely positive on scan. One patient developed a human antichimeric antibody response predominantly to the murine portion of the antibody. The antibody cleared serum with a median T(1/2alpha) of 6.53 hr and a T(1/2beta) of 90.87 hr. Interpatient variations in serum clearance rates were observed and were secondary to differences in clearance and metabolic rates of antibody-antigen complexes by the liver. One patient demonstrated very rapid clearance of antibody by the liver, which compromised antibody localization to the primary tumor. Antibody uptake in primary and metastatic tumors ranged from 0.5% to 10.5% injected dose/kg, resulting in estimated radiation doses ranging from 0.97 to 21.3 cGy/mCi 90Y. Antibody uptake in regional lymph nodes ranged from 1.3% to 377% injected dose/kg, resulting in estimated radiation doses ranging from 2.0 to 617 cGy/mCi 90Y.

CONCLUSION

Chimeric T84.66 demonstrated tumor targeting that was comparable to that of other radiolabeled intact anti-CEA Mabs. Its immunogenicity after single administration was lower than murine Mabs. These properties make cT84.66 or a lower molecular weight derivative attractive for further evaluation as an imaging agent. These same properties also make it appropriate for future evaluation in Phase I therapy trials. Finally, a wide variation in the rate of antibody clearance was observed, with one patient demonstrating very slow clearance, resulting in the highest estimated marrow dose of the group, and one patient demonstrating unusually rapid clearance, resulting in poor antibody localization to tumor. Data from this study suggest that serum CEA levels, antibody-antigen complex clearance and, therefore, antibody clearance are influenced by both the production and clearance rates of CEA. This underscores the need to further identify, characterize and understand those factors that influence the biodistribution and clearance of radiolabeled anti-CEA antibodies to allow for better selection of patients for therapy and rational planning of radioimmunotherapy.

Three-dimensional reconstruction of curves from pairs of projection views in the presence of error. I. Algorithms

We have previously described an approach to 3D intracerebral vascular reconstruction that uses an MRA as a reconstruction base. Additional vessels seen only by angiography are added by segmenting 2D curves from projection angiograms and reconstructing these curves into 3D, building upon the MRA. Intracerebral vascular reconstruction is difficult for at least two reasons. First, 2D curves must be associated on projection images even when the human eye cannot do so. Second, 3D curves must be reconstructed in the presence of errors such as misregistration, image distortion, and misdefinition of 2D curves. This paper is the first of two that address the specific issue of reconstruction of a 3D curve from a given pair of 2D curves in the presence of error. The method explicitly separates what can and cannot be determined from a pair of projection views. It is also capable of recognizing interruptions produced by viewplane errors, of continuing reconstruction beyond such interruptions, and of localizing and estimating the magnitude of the interruptions. These measurements can also be used to estimate the lengths of regional disparities between a pair of 2D curves, leading to a quantitative estimate of the capacity of a pair of 2D curves to combine to create a 3D object (match value). Match values can be used, in turn, as part of the strategy for automatically associating pairs of 2D curves. This paper provides methods for reconstructing a given pair of 2D curves into 3D in the presence of error and for calculating match values. Error analysis is given in the companion report.

Three-dimensional reconstruction of curves from pairs of projection views in the presence of error. II. Analysis of error

We have previously described an approach to 3D intracerebral vascular reconstruction that uses an MRA as a reconstruction base. Additional vessels seen only by angiography are added by segmenting 2D curves from projection angiograms and reconstructing these curves into 3D, building upon the MRA. This paper is the second of two that discuss the specific problem of reconstructing a 3D curve from a given pair of 2D curves in the presence of error. The method presented is capable of detecting and handling many errors produced by misregistration, image distortion, or misdefinition of 2D curves. The first paper gives an algorithm. The current paper discusses factors affecting the accuracy of a reconstructed curve, with emphasis upon registration error. We analyze the spatial accuracy of a reconstructed point in terms of the relationships between pixel size, relative viewing angle, 3D point location, and registration error. We provide a theoretical framework that, given the known error properties of a registration algorithm, allows optimization of the viewing geometry so as to produce the highest precision of point reconstruction. A major focus is the effect of registration error upon the reconstruction of a curve. We subdivide registration error into two types, one of which produces smoothly continuous point placement errors and the other of which produces pixel pairing errors. We test our ability to reconstruct a 3D curve in the presence of both. Finally, we summarize approaches to other sources of error. We conclude with a list of recommendations to optimize reconstruction accuracy. When projection points are associated by the rules of epipolar geometry, viewplane point displacements should not exceed 1.5-2 mm along the axis perpendicular to epipolar planes.

Control of the thermal lensing effect with different pump light distributions

We built a 32-laser-diode-formed virtual point source pumping system and achieved different pump light distributions from central intense to central uniform and central depressed. Continuous wave TEM(00) operations of a Nd:YAG laser were performed under these pump light distributions and their thermal lensing effects were estimated. Results show that the operation under central depressed pump light distribution has the lowest thermal lensing effect and can provide the highest output power, which agrees with the results derived from the theoretical calculation with the heat conduction equation.

Comparison of cerclage techniques using a hose clamp versus monofilament cerclage wire or cable

To assess the compressive force generated by different techniques of cerclage wiring, the compression produced by 6 different cerclage techniques, including monofilament wires, Dall-Miles cables (Howmedica, Rutherford, NJ), and hose clamps, was measured. Tests were performed on both a polysulfone cylinder model and a cadaver bone model. The hose clamp generated significantly higher compression force than any other cerclage device tested. Doubled wires produced similar compressive force as the cables. As the hose clamp is the least expensive and produces the maximum compression, it may be advantageous in instances in which maximum compression is desirable as a temporary device, but because it is not implantable, it must be replaced by other techniques prior to wound closure. The Dall-Miles cable is expensive and its compressive force can be equaled at lower cost by a doubled wire. The use of a single strand of monofilament wire was the least effective.

Differential expression of transforming growth factor-beta receptors in rat kidney development

Transforming growth factor-beta 1 (TGF-beta 1) is strongly expressed during embryogenesis and in sites undergoing intense development and morphogenesis. Two receptor serine/threonine kinases (types I and II) have been identified as signal-transducing TGF-beta receptors. This study was undertaken to further explore the role of the distinct TGF-beta receptors during kidney development. The species-specific sequence information for the two T beta R-I, namely, activin receptor-like kinase-5 (ALK-5) and Tsk7L, in the rat was sought. Two full-length T beta R-I cDNAs were cloned from a neonatal rat kidney and lung libraries, and sequencing revealed that they were the rat homologs of human ALK-5 and murine Tsk7L. Both types I and II TGF-beta receptors are expressed in the kidney as determined by Northern blot analysis. T beta R-II mRNA abundance was significantly greater in the neonatal rat kidney compared with the adult rat kidney. Similarly, ALK-5 mRNA was more highly expressed in the fetal and neonatal rat kidney than the adult rat kidney. In contrast, there was no significant difference in Tsk7L mRNA abundance among the fetal, neonatal, and adult rat kidney. Thus, based on these findings, both T beta R-II and ALK-5 are developmentally regulated in the kidney. Increased expression of T beta R-II and ALK-5 proteins in the developing kidney was confirmed by immunohistochemistry. Interestingly, the two TGF-beta receptors did not entirely colocalize, raising the intriguing possibility that other TGF-beta signaling receptors may be involved.

Terbenzimidazoles: influence of 2"-, 4-, and 5-substituents on cytotoxicity and relative potency as topoisomerase I poisons

Terbenzimidazoles poison the nuclear enzyme topoisomerase I and possess significant cytotoxic activity against several human tumor cell lines. The relative pharmacological activity of 4,5- and 5,6-benzoterbenzimidazoles was compared to that of 5-phenylterbenzimidazole (3). 5,6-Benzoterbenzimidazole is inactive as a topoisomerase I poison and did not exhibit significant cytotoxic activity. In contrast, 4,5-benzoterbenzimidazole retained activity as a topoisomerase I poison but exhibited weak cytotoxic activity relative to 3. While 5-(1-naphthyl)terbenzimidazole is less potent than 3 as a topoisomerase I poison and cytotoxic agent, 5-(2-naphthyl)-terbenzimidazole has comparable activity to 3. The presence of a p-methoxy or p-chloro substituent on the phenyl moiety did not dramatically alter the pharmacological activity of 3. Several analogs of 3 were synthesized wherein the 2"-substituent varied from methyl, ethyl, propyl, isopropyl, phenyl to p-methoxyphenyl. Evaluation of the intrinsic activity of these analogs as topoisomerase I poisons indicates that topoisomerase I poisoning was not diminished by the presence of a methyl, ethyl, propyl, and isopropyl substituent at the 2"-position. Among the various 2"-substituted analogs evaluated, only in the case of 2"-(p-methoxyphenyl)-5-phenylterbenzimidazole was a significant decrease in cytotoxicity observed.

[A comparative study of lanthanum, cerium and fluoride on the prevention of root surface caries by various procedure]

In order to evaluate the anticaries effects of several trace elements by combined and respective treating procedure, studies on inhibiting demineralization and improving remineralization were carried out with lanthanum, cerium and fluoride in a pH-cycling condition. The analysis of polarized microscope and electron microprobe demonstrated that the lanthanum and fluoride to an acetate buffer solutions had less severe demineralization of root surface than individual lanthanum or fluoride to the solution. The former, furthermore, precipitated a compound membrane which may be F-La(Ce)-Ca containing crystal on the root surface, and showed a better resistibility to acid. A further discussion was made from the viewpoint of crystal physiochemistry.