Phase II study of fludarabine and alpha-interferon in patients with low-grade non-Hodgkin's lymphoma

BACKGROUND AND OBJECTIVES

Low-grade non-Hodgkin's lymphoma (NHL) remains incurable with standard dose chemotherapy. Nucleoside analogs such as fludarabine are effective, but even when used as initial therapy, the median duration of remission ranges from only 16 to 24 months. Interferon (IFN) is also active and has been investigated both by incorporating it into the chemotherapy regimen and/or as maintenance therapy, where it may prolong remission. We designed a phase II trial of alternating fludarabine and IFNalpha2a to determine response rate, time to progression and toxicity of this regimen in patients with advanced stage low-grade NHL or mantle cell lymphoma.

DESIGN AND METHODS

Patients had received 0-2 prior regimens that did not include nucleoside analogs or IFN and had adequate organ function. Fludarabine was administered intravenously at 25 mg/m2/day for 5 days once every 6 weeks with IFN in weeks 4 and 5 at 3x10(6) U/m2 subcutaneously three times weekly for 6 doses. Treatment continued in responders for 2 cycles past maximal response (minimum 6 cycles). No maintenance was given.

RESULTS

Between 1994 and 1999, 31 patients were accrued and were evaluable for toxicity, with 29 eligible for evaluation of response. Toxicity was primarily myelosuppression, with grade 3 neutropenia in 12 patients and grade 4 thrombocytopenia in one patient. The overall response rate was 51.7% (15/29), including 6 complete and 9 partial responses. With a median follow-up of 35.6 months, the median overall survival was 60.8 months, and the median time to disease progression (TTP) was 12.6 months. Of the 15 responding patients, treatment-naive patients had a median response duration of 39.6 months with a median TTP of 42.1 months, while the median response duration was 5.2 months with a median TTP of 14.5 months in patients who had received prior treatment (p=0.0065 and 0.0374, respectively).

INTERPRETATION AND CONCLUSIONS

This schedule of alternating fludarabine with IFN does not seem to increase response rate appreciably, but there are some prolonged responses, particularly in previously untreated patients. Given the non-overlapping toxicities of IFN with those of chemotherapy and antibody-based therapeutics, there may be a role for combination therapies, especially if the biological basis of response to IFN can be elucidated.

Enhanced efficacy of therapy with antisense BCL-2 oligonucleotides plus anti-CD20 monoclonal antibody in scid mouse/human lymphoma xenografts

Monoclonal anti-CD20 antibody (rituximab) is active, but not curative, therapy for B-cell non-Hodgkin's lymphoma. BCL-2 is an antiapoptotic protein whose expression is dysregulated in most indolent B-cell malignancies. Antisense oligonucleotides (AS-ODNs) that down-regulate BCL-2 expression induce apoptosis and chemosensitize B-cell lymphoma cells. We hypothesized that BCL-2 down-regulation by AS-ODNs would sensitize cells to rituximab and improve therapeutic results. There is enhanced apoptosis and reduction in cell numbers when DoHH2 cells are treated in vitro with rituximab plus BCL-2 AS-ODNs, compared with either agent alone. There is little in vitro effect on WSU-FSCCL cells by rituximab, AS-ODNs that down-regulate BCL-2 by targeting the immunoglobulin portions of the BCL-2-immunoglobulin fusion molecule, or a combination of the two. The combination is more effective than either agent alone in clearing DoHH2 cells from ascites in scid mice. Combination therapy with AS-BCL-2-ODNs and rituximab significantly prolongs survival in both the DoHH2 and WSU-FSCCL models. With higher and repeated doses, this combination could be curative. We conclude that the combination of rituximab and antisense-mediated down-regulation of BCL-2 has enhanced activity against human lymphoma, prolongs survival, and could cure mice bearing human lymphoma. This merits investigation in clinical trials.

Enhanced efficacy of therapy with antisense BCL-2 oligonucleotides plus anti-CD20 monoclonal antibody in scid mouse/human lymphoma xenografts

Monoclonal anti-CD20 antibody (rituximab) is active, but not curative, therapy for B-cell non-Hodgkin's lymphoma. BCL-2 is an antiapoptotic protein whose expression is dysregulated in most indolent B-cell malignancies. Antisense oligonucleotides (AS-ODNs) that down-regulate BCL-2 expression induce apoptosis and chemosensitize B-cell lymphoma cells. We hypothesized that BCL-2 down-regulation by AS-ODNs would sensitize cells to rituximab and improve therapeutic results. There is enhanced apoptosis and reduction in cell numbers when DoHH2 cells are treated in vitro with rituximab plus BCL-2 AS-ODNs, compared with either agent alone. There is little in vitro effect on WSU-FSCCL cells by rituximab, AS-ODNs that down-regulate BCL-2 by targeting the immunoglobulin portions of the BCL-2-immunoglobulin fusion molecule, or a combination of the two. The combination is more effective than either agent alone in clearing DoHH2 cells from ascites in scid mice. Combination therapy with AS-BCL-2-ODNs and rituximab significantly prolongs survival in both the DoHH2 and WSU-FSCCL models. With higher and repeated doses, this combination could be curative. We conclude that the combination of rituximab and antisense-mediated down-regulation of BCL-2 has enhanced activity against human lymphoma, prolongs survival, and could cure mice bearing human lymphoma. This merits investigation in clinical trials.

The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)

The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline.

Phase II study of paclitaxel and estramustine in patients with recurrent and refractory non-Hodgkin lymphoma

BACKGROUND

The current study was conducted to evaluate the efficacy of paclitaxel, administered weekly or once every 3 weeks, in combination with oral estramustine phosphate (EMP) in patients with recurrent or refractory aggressive non-Hodgkin lymphoma (NHL).

METHODS

Between February 1996 and February 2001, 23 patients with recurrent NHL were enrolled onto this Phase II trial. The median age for all patients was 65 years (range, 27-80 years). The initial 12 patients (who received a mean number of 2.4 prior treatments, including 1 patient who received a prior peripheral blood stem cell transplant) received paclitaxel at a dose of 175 mg/m2 given as a 3-hour intravenous infusion every 21 days. The next 11 patients (who received a mean number of 2.8 prior treatments, including 1 patient who received prior peripheral blood stem cell transplant) were registered (1 patient refused treatment) to receive paclitaxel at a dose of 80 mg/m2 as a 1-hour intravenous infusion weekly for 6 weeks of an 8-week cycle. All patients received EMP at a dose of 600 mg/m2 orally per day beginning the day prior to each dose of paclitaxel for a total of 3 days.

RESULTS

When paclitaxel was administered every 21 days, 4 partial responses were observed in 12 evaluable patients (33.3%). The median survival was 147 days. The median duration of response was 102 days (range, 42-127 days) and the median time to disease progression was 66 days. Grade 3 and Grade 4 neutropenia (according to the revised version of the Common Toxicity Criteria of the National Cancer Institute) were observed in 5 patients (42%) in this group. In an attempt to reduce the incidence of myelosuppression, paclitaxel dosing was changed to weekly dosing. In the cohort of patients receiving weekly paclitaxel, an objective response was reported to occur in 3 (1 complete response and 2 partial responses) of 11 evaluable patients (27%). The median survival was 132 days (range, 33-462 days). The median duration of response was 64 days and the median time to disease progression was 57 days. There was no significant difference noted between the cohort receiving paclitaxel three times weekly and those receiving paclitaxel weekly with regard to overall survival and time to disease progression (P = 0.7 and P = 0.8, respectively by the log-rank test). Grade 3 or 4 neutropenia was observed in only 2 of 11 patients (18%) in the weekly paclitaxel group. There were no significant differences noted in terms of thrombocytopenia, anemia, nausea, anorexia, or fatigue between the treatment groups.

CONCLUSIONS

Paclitaxel given once weekly or three times weekly, in combination with oral EMP, was found to have comparable efficacy in patients with recurrent NHL, with an overall response rate of 30%. The response rate was found to be higher than that reported in prior studies of paclitaxel as a single agent in the treatment of NHL, suggesting that EMP may enhance paclitaxel efficacy in patients with NHL. Hematologic toxicity was diminished when paclitaxel was administered on a weekly schedule. The minimal myelotoxicity of weekly paclitaxel makes this a potentially attractive agent for combination regimens for patients with recurrent/refractory NHL.

Finasteride and bicalutamide as primary hormonal therapy in patients with advanced adenocarcinoma of the prostate

BACKGROUND

Medical or surgical castration is effective in advanced prostate cancer but with profound side-effects, particularly on sexual function. Effective, less toxic therapies are needed. This study examined whether the addition of finasteride to high-dose bicalutamide enhanced disease control, as measured by additional decreases in serum prostate-specific antigen (PSA).

PATIENTS AND METHODS

Forty-one patients with advanced prostate cancer received bicalutamide (150 mg/day). Finasteride (5 mg/day) was added at first PSA nadir. Serum PSA was measured every 2 weeks until disease progression. Questionnaires were administered to assess sexual function.

RESULTS

Median follow-up is 3.9 years. At the first PSA nadir, median decrease in PSA from baseline was 96.5%. Thirty of 41 patients (73%) achieved a second PSA nadir and median decrease of 98.5% from baseline. Median time to each nadir was 3.7 and 5.8 weeks, respectively. Median time to treatment failure was 21.3 months. Toxicities were minor, including gynecomastia. Seventeen of 29 (59%) and 12 of 24 (50%) men had normal sex drive at baseline and at second PSA nadir, respectively. One-third of men had spontaneous erection at both time points.

CONCLUSION

Finasteride provides additional intracellular androgen blockade when added to bicalutamide. Duration of control is comparable to castration, with preserved sexual function in some patients.

Predicting treatment response in non-Hodgkin’s lymphoma from the pretreatment tumor content of phosphoethanolamine plus phosphocholine1

RATIONALE AND OBJECTIVES

Phosphoethanolamine and phosphocholine, shown to be elevated in tumors and possibly related to apoptotic signaling, have the potential to be prognostic variables of cancer treatment.

MATERIALS AND METHODS

The sum of phosphoethanolamine and phosphocholine normalized by nucleotide-triphosphates was determined in tumors of non-Hodgkin's lymphoma (NHL) patients via in vivo 31P MR spectroscopy.

RESULTS

The normalized sum of phosphoethanolamine and phosphocholine showed significant differences in tumors of patients who had a complete response to treatment against those who did not (t-test: 1.45 +/- 0.15, mean +/- standard error, n = 10 vs. 2.28 +/- 0.15, n = 17, P < .001; Fisher test: P < .04; sensitivity and specificity approximately equal to 70%). This parameter also showed significant differences among treatment responses in the previously untreated and aggressive subgroups and in the low and low-intermediate-risk subgroups determined by the international prognostic index (IPI). Further, distinctly different treatment response cutoffs for the parameter were found in different risk groups. When these risk-dependent cutoffs were used, the Fisher test of the whole group improved (P < .0002, sensitivity 80%, specificity 94%). The normalized sum of phosphoethanolamine and phosphocholine and the IPI were better predictor covariates for time to treatment failure when fitted interactively in a Cox regression (P < .0003) than when fitted independently. When time to treatment failure was used as a surrogate of survival in Kaplan-Meier analysis, the interaction of both covariates segregated the cases significantly (P < .008). There was no significance with each covariate independently.

CONCLUSION

The normalized sum of phosphoethanolamine and phosphocholine measured before treatment successfully predicts long-term response to treatment and time to treatment failure in non-Hodgkin's lymphoma, particularly when combined with the IPI.

Removing the effect of SVD algorithmic artifacts present in quantitative MR perfusion studies

Quantitative cerebral blood flow (CBF) values can be obtained from dynamic susceptibility contrast (DSC) MR perfusion studies using the standard singular value decomposition (sSVD) deconvolution algorithm. Reports in the literature from simulation and in vivo studies suggest that CBF estimates obtained using sSVD deconvolution depend on the arterial-tissue delay (ATD). By contrast, Fourier transform (FT) deconvolution produces CBF estimates that are independent of ATD. The diagnostic reliability of quantitative CBF measurements to define areas of normal tissue flow and tissue at risk is brought into doubt by such gross sensitivity to the specifics of the deconvolution approach. This variation of CBF values with ATD is shown to be an artifact associated with the current implementation of the sSVD deconvolution algorithm. A reformulated version of the SVD deconvolution algorithm (rSVD) is presented and compared to the standard SVD algorithm through simulation and patient case studies.

Rituximab (monoclonal anti-CD20 antibody): mechanisms of action and resistance

Rituximab, a chimeric monoclonal antibody targeted against the pan-B-cell marker CD20, was the first monoclonal antibody to be approved for therapeutic use. Treatment with rituximab at standard weekly dosing is effective in more than 50% of patients with relapsed or refractory CD20-positive follicular non-Hodgkin's lymphoma, but is not curative. It is less effective in other subtypes of CD20-positive lymphoma and for retreatment, even with CD20 still expressed. Thus, binding of rituximab to CD20 is not sufficient to kill many lymphoma cells, indicating that there are mechanisms of resistance. Mechanisms of cell destruction that have been demonstrated to be activated by rituximab binding to CD20 include direct signaling of apoptosis, complement activation and cell-mediated cytotoxicity. The relative importance of each of these mechanisms in determining clinical response to rituximab treatment remains a matter of conjecture. Thus, the role of various resistance pathways, some documented in experimental systems and others still hypothetical, remains uncertain. Resistance could potentially be mediated by alterations in CD20 expression or signaling, elevated apoptotic threshold, modulation of complement activity or diminished cellular cytotoxicity. As the first of an expanding class of anticancer agents, lessons learned regarding the mechanism of rituximab action and resistance will be of increasing importance.

Barking up the wrong tree? A survey of dog bite wound management

OBJECTIVES

Several trials have been published examining the role of antibiotics in dog bite wound management. A meta-analysis of these suggests that there is very little benefit to routine antibiotic prescription in these patients. All papers however incorporated rigorous wound care regimens involving large volume irrigation.

METHODS

The authors undertook a telephone survey to investigate wound care and prescribing practice in bite wound management in accident and emergency and minor injury units in the Yorkshire region.

RESULTS

Twenty one departments were contacted. Only 10% of departments routinely irrigate these wounds. Antibiotics are prescribed routinely in 71%.

CONCLUSIONS

Management of dog bite wounds would not seem to be evidence based in most departments in this sample.

Phosphomonoester concentrations differ between chronic lymphocytic leukemia cells and normal human lymphocytes

Levels of phospholipid-related metabolites of chronic lymphocytic leukemia lymphocytes (CLL) and normal human lymphocytes were quantified using phosphorus magnetic resonance spectroscopy. The CLL cells versus normal lymphocytes showed significant increases of phosphoethanolamine(Etn-P) (8.11+/-2.10 mean+/-S.E., micromol/g wet weight, n=12 versus 3.63+/-1.10, n=3, P<or=0.002), phosphocholine (2.10+/-0.37, n=12 versus 0.36+/-0.09, n=3, P<or=0.01), glycerophosphoethanolamine (0.26+/-0.03, n=10 versus 0.11+/-0.05, n=3, P<or=0.004), and glycerophosphocholine (0.33+/-0.03, n=10 versus 0.17+/-0.05, n=3, P<or=0.003). Further, the phospholipid precursor ethanolamine (Eth) was studied in blood and was found significantly lowered in CLL patients (4.6+/-1.6 microM, n=25) compared to normal volunteers (7.7+/-2.5, n=12, P<or=0.001). Increased intermediates with depletion of precursors suggest the presence of sustained phospholipid metabolism activation in CLL.

Hazard identification by methods of animal-based toxicology

This paper is one of several prepared under the project "Food Safety In Europe: Risk Assessment of Chemicals in Food and Diet" (FOSIE), a European Commission Concerted Action Programme, organised by the International Life Sciences Institute, Europe (ILSI). The aim of the FOSIE project is to review the current state of the science of risk assessment of chemicals in food and diet, by consideration of the four stages of risk assessment, that is, hazard identification, hazard characterisation, exposure assessment and risk characterisation. The contribution of animal-based methods in toxicology to hazard identification of chemicals in food and diet is discussed. The importance of first applying existing technical and chemical knowledge to the design of safety testing programs for food chemicals is emphasised. There is consideration of the presently available and commonly used toxicity testing approaches and methodologies, including acute and repeated dose toxicity, reproductive and developmental toxicity, neurotoxicity, genotoxicity, carcinogenicity, immunotoxicity and food allergy. They are considered from the perspective of whether they are appropriate for assessing food chemicals and whether they are adequate to detect currently known or anticipated hazards from food. Gaps in knowledge and future research needs are identified; research on these could lead to improvements in the methods of hazard identification for food chemicals. The potential impact of some emerging techniques and toxicological issues on hazard identification for food chemicals, such as new measurement techniques, the use of transgenic animals, assessment of hormone balance and the possibilities for conducting studies in which common human diseases have been modelled, is also considered.

Application of transmission near-infrared spectroscopy to uniformity of content testing of intact steroid tablets

Transmission near-infrared (NIR) spectroscopy was used for the rapid and non-destructive determination of the content of a hormone steroid in single intact tablets. Tablets produced for clinical trial purposes containing 5, 10, 15, 20 and 30 mg (2.94, 5.88, 8.82, 11.76 and 17.64% m/m, respectively) were used to develop calibration models without the need to specially prepare any out of specification tablets. Reference values for the individual tablets used in the NIR calibration models and test set were measured by reversed-phase high performance liquid chromatography (HPLC). Partial least squares regression using standard normal variate transformed second-derivative spectra over the range 800 to 1040 nm gave the optimum calibration model with a standard error of calibration of 0.52 mg per tablet. Measurements of an independent test set gave comparable results (standard error of prediction 0.31 mg per tablet). Measurement errors for a single tablet (RSD < 2.5% for a given active level) were sufficiently small to allow the procedure to be applied to pharmacopoeial uniformity of content testing of batches of these tablets and permitted the non-destructive testing of 30 tablets in under 20 min as compared to 6 h by HPLC.

Lead poisoning of waterfowl by contaminated sediment in the Coeur d'Alene River

The Coeur d'Alene River basin in Idaho has been contaminated by mine tailings that have impaired the health of wildlife since the early 1900s. In other parts of the world, virtually all lead poisoning of waterfowl is caused by the ingestion of manmade lead artifacts, primarily spent lead shotshell pellets or, occasionally, fishing sinkers. However, in the Coeur d'Alene River basin in Idaho, nonartifactual lead poisoning was the ultimate cause of death of most of 219 (77%) of 285 waterfowl carcasses that had been found sick or dead from 1992 through 1997. The majority of these 219 waterfowl (172 tundra swans [Cygnus columbianus], 33 Canada geese [Branta canadensis], and 14 other species) were poisoned by ingesting river sediment that was contaminated with lead. The next most common cause of death (20 instances, 7%) was lead poisoning accompanied by ingested shotshell pellets. The remaining 46 waterfowl succumbed to trauma, infectious diseases (aspergillosis, avian cholera, tuberculosis), or miscellaneous problems, or the cause of death was not determined.

Pamidronate to prevent bone loss during androgen-deprivation therapy for prostate cancer

BACKGROUND

Treatment with a gonadotropin-releasing hormone agonist decreases bone mineral density and increases the risk of fracture in men with prostate cancer. We conducted a controlled study of the prevention of osteoporosis in men undergoing treatment with a gonadotropin-releasing hormone agonist.

METHODS

In a 48-week, open-label study, we randomly assigned 47 men with advanced or recurrent prostate cancer and no bone metastases to receive either leuprolide alone or leuprolide and pamidronate (60 mg intravenously every 12 weeks). Bone mineral density of the lumbar spine and the proximal femur was measured by dual-energy x-ray absorptiometry. Trabecular bone mineral density of the lumbar spine was measured by quantitative computed tomography. Forty-one men completed the study.

RESULTS

In men treated with leuprolide alone, the mean (+/-SE) bone mineral density decreased by 3.3+/-0.7 percent in the lumbar spine, 2.1+/-0.6 percent in the trochanter, and 1.8+/-0.4 percent in the total hip, and the mean trabecular bone mineral density of the lumbar spine decreased by 8.5+/-1.8 percent (P<0.001 for each comparison with the base-line value). In contrast, the mean bone mineral density did not change significantly at any skeletal site in men treated with both leuprolide and pamidronate. There were significant differences between the two groups in the mean changes in bone mineral density at 48 weeks in the lumbar spine (P<0.001), trochanter (P = 0.003), total hip (P=0.005), and trabecular bone of the lumbar spine (P=0.02).

CONCLUSIONS

Pamidronate prevents bone loss in the hip and lumbar spine in men receiving treatment for prostate cancer with a gonadotropin-releasing hormone agonist.

Regioselective aromatic borylation in an inert solvent

[reaction: see text]. A protocol for performing Rh catalyzed aromatic borylations in cyclohexane has been devised. Borylation at the 5-position of several 1,3-substituted aromatic species ranging from electron-rich (1,3-(NMe(2))(2)C(6)H(4)) to electron-deficient (1,3-(CF(3))(2)C(6)H(4)) yields the corresponding aryl boronate esters. Veratrole was selectively borylated at the 4-position, thus extending regioselectivity to 1,2-substituted benzenes. Selective borylation at the 3-position of an N-protected pyrrole has also been demonstrated, providing a valuable reagent for cross-coupling reactions in a single step.

Monocular optical constraints on collision control

A simulated ball-hitting task was used to explore the optical basis for collision control. Ball speed and size were manipulated in Experiments 1 and 2. Results showed a tendency for participants to respond earlier to slower and larger balls. Early in practice, participants would consistently miss the slowest and largest balls. Experiments 3 and 4 examined performance as a function of the range of speeds. Performance for identical speeds differed depending on whether the speeds were fastest or slowest within a range. Asymmetric transfer between the 2 ranges of speeds showed that those trained with slow speeds were very successful when tested with a faster range of speeds. Those trained with fast speeds did not do as well when tested on slower speeds. The pattern of results across 4 experiments suggests that participants were using optical angle and expansion rate as separate degrees of freedom for solving the collision task.

Neoadjuvant docetaxel followed by radical prostatectomy in patients with high-risk localized prostate cancer: a preliminary report

Effective treatment options for high-risk localized prostate cancer are limited. Patients at high risk for recurrence include those with biopsy Gleason scores of 8 to 10, prostate specific antigen (PSA) levels > 20 ng/mL, and clinical stage T3 disease. Docetaxel chemotherapy is active in hormone-refractory prostate cancer, either combined with estramustine or used as a single agent. To determine if systemic therapy can improve the outcome of radical prostatectomy in men with high-risk localized prostate cancer, we are undertaking a pilot phase II clinical trial of weekly docetaxel at 36 mg/m(2) for up to 6 months, followed by surgery. Patients are monitored with weekly visits, monthly digital rectal examinations, PSA measurement, and testosterone tests, and endorectal magnetic resonance imaging done at baseline, after two cycles, and again after six cycles. To date, 15 patients have been enrolled, and 70 cycles of chemotherapy have been administered. Toxicity has been mostly grade 1 in intensity, and fatigue has been the most common grade 2 toxicity reported. The primary endpoint of the trial is measurement of pathologic complete response rate, for which data are not yet available. Recruitment to the trial is ongoing.

The structure of dentine in the apical region of human teeth

AIM

To study the structure of the apical region of human teeth with emphasis on dentinal tubules and their branches.

METHODOLOGY

This descriptive histological study employed demineralized stained sections for light microscopy, demineralized unstained sections for scanning electron microscopy, and undemineralized, acid-etched specimens for confocal tandem scanning microscopy.

RESULTS

The apical portion of human teeth showed marked variations in structure, including accessory root canals, areas of resorption and repaired resorptions, occasional attached, embedded and free pulp stones, varied amounts of irregular secondary dentine, and even cementum-like tissue lining the apical root canal wall. The apex often deviated from the long axis of the root canal. Primary dentinal tubules were irregular in direction and density. Some areas were devoid of tubules.

CONCLUSIONS

The irregular and variable structure of the apical region of human teeth represent special challenges during endodontic therapy. Obturation techniques based on the penetration of adhesives into dentinal tubules are unlikely to be successful and adhesive techniques must depend on impregnation of a hybrid layer.

Low bone mineral density in hormone-naïve men with prostate carcinoma

BACKGROUND

The objective of this study was to determine the prevalence of low bone mineral density in men with prostate carcinoma and no history of androgen-deprivation therapy.

METHODS

The authors conducted a cross-sectional study in 41 hormone-naïve men with locally advanced, lymph node positive, or recurrent prostate carcinoma and no radiographic evidence of bone metastases. Bone mineral density of the total hip, posterior-anterior (PA) lumbar spine, and lateral lumbar spine was determined by dual-energy X-ray absorptiometry (DXA) using a densitometer. Trabecular bone mineral density of the lumbar spine was determined by quantitative computed tomography (QCT). Bone mineral density results were expressed in standard deviation units relative to young adult men (T score) and relative to age-matched men (Z score).

RESULTS

Fourteen of 41 men (34%; 95% confidence interval [95% CI], 20-51%) had T scores < -1.0 at one or more skeletal sites by DXA, 12 of 41 men (29%; 95% CI, 16-42%) had T scores between -1.0 and -2.5, and 2 of 41 men (5%; 95% CI, 1-17%) had T scores < -2.5. Thirty-nine of 41 men (95%; 95% CI, 83-99%) had T scores < -1.0 by QCT, 13 of 41 men (31%; 95% CI 18-48%) had T scores between -1.0 and -2.5, and 26 of 41 men (63%; 95% CI, 47-78%) had T scores < -2.5. T scores for trabecular bone mineral density of the lumbar spine were significantly lower than T scores for either the total hip (P < 0.001) or the PA lumbar spine (P < 0.001). The mean Z score for trabecular bone mineral density of the lumbar spine was -0.7 +/- 0.9. Hypogonadism, hypovitaminosis D, and dietary calcium intakes below the Recommended Daily Allowance were observed in 20%, and 17%, and 59% of study participants, respectively.

CONCLUSIONS

Many hormone-naïve men with prostate carcinoma have low bone mineral density. QCT is a more sensitive method than DXA for diagnosing low bone mineral density in this patient population. Trabecular bone mineral density is lower than expected for age and risk factors for osteoporosis are common.

Rectal prolapse in women with other defects of pelvic floor support

OBJECTIVES

We describe a series of patients with rectal prolapse who had other pelvic floor defects.

STUDY DESIGN

Patients with rectal prolapse that we examined between 1990 and 2000 were reviewed.

RESULTS

During this time frame 55 patients with rectal prolapse were seen by one of us. Fifty-two of these patients had other defects of pelvic floor support and are the subject of this report. The diagnosis was established in all patients with video defecography. Thirty-nine of the patients had internal (occult) prolapse that simulated either a rectocele or an enterocele. The mean number of surgical procedures for pelvic floor support before the diagnosis of rectal prolapse was 1.5. Thirty-one patients underwent a sigmoid resection with rectopexy, 12 underwent a rectopexy alone, 3 underwent a Ripstein procedure, 2 elderly patients had physical therapy alone, and the other 4 patients had surgical correction of the rectal prolapse before being referred for repair of vaginal vault prolapse. Other procedures performed simultaneously included sacral colpopexy, sacrospinous suspension, rectopubic urethropexy, and abdominal fixation of the vagina to the uterosacral ligaments.

CONCLUSIONS

Rectal prolapse frequently coexists with other pelvic floor defects. Internal rectal prolapse may simulate a rectocele or enterocele and requires defecography to establish the diagnosis. Rectopexy (with or without sigmoid resection) is a satisfactory technique for correction and may be combined with other reconstructive procedures on the pelvic floor.

Complementary and alternative therapies for advanced prostate cancer

This article reviews complementary and alternative therapies for advanced prostate cancer. This is not a comprehensive survey of nontraditional therapies for prostate cancer. Rather, this review focuses on alternative and complementary therapies with published studies to evaluate efficacy and safety. Three areas are addressed: alternative forms of hormonal therapy, management of side effects of hormonal therapy, and management of skeletal complications.

A gain-of-function mutation in the sodium channel gene Scn2a results in seizures and behavioral abnormalities

The GAL879-881QQQ mutation in the cytoplasmic S4-S5 linker of domain 2 of the rat brain IIA sodium channel (Na(v)1.2) results in slowed inactivation and increased persistent current when expressed in Xenopus oocytes. The neuron-specific enolase promoter was used to direct in vivo expression of the mutated channel in transgenic mice. Three transgenic lines exhibited seizures, and line Q54 was characterized in detail. The seizures in these mice began at two months of age and were accompanied by behavioral arrest and stereotyped repetitive behaviors. Continuous electroencephalogram monitoring detected focal seizure activity in the hippocampus, which in some instances generalized to involve the cortex. Hippocampal CA1 neurons isolated from presymptomatic Q54 mice exhibited increased persistent sodium current which may underlie hyperexcitability in the hippocampus. During the progression of the disorder there was extensive cell loss and gliosis within the hippocampus in areas CA1, CA2, CA3 and the hilus. The lifespan of Q54 mice was shortened and only 25% of the mice survived beyond six months of age. Four independent transgenic lines expressing the wild-type sodium channel were examined and did not exhibit any abnormalities. The transgenic Q54 mice provide a genetic model that will be useful for testing the effect of pharmacological intervention on progression of seizures caused by sodium channel dysfunction. The human ortholog, SCN2A, is a candidate gene for seizure disorders mapped to chromosome 2q22-24.

Non-destructive quantitation of spermine in human prostate tissue samples using HRMAS 1H NMR spectroscopy at 9.4 T

We present the results of a study of human prostate specimens evaluated by high resolution magic angle spinning (1)H nuclear magnetic resonance (NMR) spectroscopy at 400 MHz (9.4 T) and by quantitative histopathology. We demonstrate that NMR and pathology data can be obtained from the same intact specimens, and report for the first time a linear correlation between the NMR measured concentration of spermine, a proposed endogenous inhibitor to prostate cancer growth, and the volume percentage of normal prostatic epithelial cells as quantified by histopathology. Our results show that NMR may serve as a critical tool for the investigation of the inhibitory mechanism of spermine in human subjects.

Monocular optical constraints on collision control

A simulated ball-hitting task was used to explore the optical basis for collision control. Ball speed and size were manipulated in Experiments 1 and 2. Results showed a tendency for participants to respond earlier to slower and larger balls. Early in practice, participants would consistently miss the slowest and largest balls. Experiments 3 and 4 examined performance as a function of the range of speeds. Performance for identical speeds differed depending on whether the speeds were fastest or slowest within a range. Asymmetric transfer between the 2 ranges of speeds showed that those trained with slow speeds were very successful when tested with a faster range of speeds. Those trained with fast speeds did not do as well when tested on slower speeds. The pattern of results across 4 experiments suggests that participants were using optical angle and expansion rate as separate degrees of freedom for solving the collision task.

Effects of gonadal steroid suppression on skeletal sensitivity to parathyroid hormone in men

Hypogonadism is associated with osteoporosis in men. GnRH- agonist-induced hypogonadism increases bone turnover and bone loss in men, but the mechanism underlying these changes is unknown. To determine whether gonadal steroid deprivation increases the skeletal sensitivity to PTH or blunts the ability of PTH to promote 1,25-dihydroxyvitamin D formation, we infused human PTH-(1-34) at a dose of 0.55 U/kg.h for 24 h, in 11 men (ages, 50-82 yr) with locally advanced, node-positive, or biochemically recurrent prostate cancer but no evidence of bone metastases. PTH infusions were performed before initiation of GnRH agonist therapy (leuprolide acetate, 22.5 mg im, every 3 months) and again after 6 months of confirmed GnRH agonist-induced hypogonadism. Serum osteocalcin (OC), bone- specific alkaline phosphatase (BSAP), N-telopeptide (NTX), whole-blood ionized calcium, and 1,25-dihydroxyvitamin D were measured at baseline and every 6 h during each PTH infusion. Urinary NTX and free deoxypyridinoline (DPD) were assessed on spot morning samples before PTH infusion and on 24-h samples collected during the PTH infusions. Sex steroid levels were lowered to the castrate range in all subjects. Baseline serum NTX levels (drawn before PTH infusion) increased from 9.1 +/- 3.7 before leuprolide therapy to 13.9 +/- 5.0 nmol bone collagen equivalents (BCE)/L after leuprolide therapy (P = 0.003). Spot urine NTX collected before PTH infusion increased from 28 +/- 8 before leuprolide therapy to 49 +/- 17 nmol BCE/mmol creatinine after leuprolide therapy (P < 0.001), and urinary DPD increased from 4.7 +/- 1.1 to 7.4 +/- 1.8 nmol BCE/mmol creatinine (P < 0.001). Baseline serum OC and BSAP levels drawn before each PTH infusion did not change before vs. after leuprolide therapy. Serum NTX levels increased significantly during PTH infusion pre-GnRH agonist therapy (P < 0.001), and the rate of increase was greater after 6 months of GnRH agonist-induced hypogonadism (P < 0.01 for the difference in rates of change before and after GnRH agonist administration). Serum OC and BSAP levels decreased during PTH infusion (P < 0.001 for OC and P = 0.002 for BSAP), but the rates of decrease did not differ before or after leuprolide therapy (P = 0.45 for OC and P: = 0.19 for BSAP). Whole-blood ionized calcium levels increased during PTH infusion (P < 0.001), and the rate of increase was greater after GnRH agonist-induced hypogonadism (P = 0.068). Serum 1,25-dihydroxyvitamin D levels increased in response to PTH infusion before leuprolide therapy (P = 0.022), but there was no difference in the rate of increase before or after leuprolide therapy (P = 0.66). The incremental increase in urinary NTX excretion, but not DPD, during PTH infusion was greater after 6 months of leuprolide therapy (P = 0.029 for NTX, P = 0.578 for DPD). We conclude that suppression of sex steroids in elderly men increases the skeletal responsiveness to the bone resorbing effects of PTH infusion but does not affect the response of bone formation markers or 1,25-dihydroxyvitamin D to PTH. Changes in skeletal sensitivity to PTH may play an important role in the pathogenesis of hypogonadal bone loss in men.

Structure-function analysis of the Shigella virulence factor IpaB

Infection by the gram-negative bacterium Shigella flexneri results in dysentery, an acute inflammatory disease of the colon. Essential events in the pathogenesis of Shigella infections include bacterial invasion of epithelial cells, escape from the phagosome, and induction of apoptosis in macrophages. The Shigella virulence factor invasion plasmid antigen B (IpaB) is required for all of these processes. Induction of apoptosis is dependent on IpaB binding to the cysteine protease caspase-1 (Casp-1). The activation of this enzyme triggers both apoptosis and release of the proinflammatory cytokine interleukin-1beta. Several IpaB mutants were generated to correlate function with protein subdomains. We determined that the N-terminal portion of IpaB is necessary for stable expression of IpaB. A putative amphipathic alpha-helical domain preserves the structure of IpaB. We found 10 consecutive residues within the amino terminus of the hydrophobic region that play a critical role in invasion, phagosomal escape, and cytotoxicity. An IpaB mutant carrying a mutation in this region binds to Casp-1 yet is not cytotoxic, even following direct delivery to the macrophage cytoplasm. These results indicate that the association between IpaB and Casp-1 is only a step in the activation of macrophage apoptosis.

Efficacy of treatment with antisense oligonucleotides complementary to immunoglobulin sequences of bcl-2/immunoglobulin fusion transcript in a t(14;18) human lymphoma-scid mouse model

In t(14;18)-positive lymphoma cells, bcl-2 is expressed from a fusion mRNA transcript containing the full coding sequence of bcl-2 and 3' immunoglobulin sequences. We reported previously that antisense oligodeoxyribonucleotides directed at the bcl-2 translational start site, as well as those targeted to immunoglobulin sequences 3' of the translocation breakpoint, down-regulate bcl-2 and inhibit growth of the t(14;18)-positive lymphoma line WSU-FSCCL in vitro. We have developed a scid mouse model with this human cell line and demonstrate that antisense oligodeoxyribonucleotides targeted to immunoglobulin c(mu) sequences down-regulate bcl-2 protein expression and induce apoptosis of WSU-FSCCL cells in vivo. This leads to prolonged survival of the mice. Targeting non-oncogenic sequences outside of the breakpoints of fusion transcripts may be a clinically useful therapeutic strategy.

A phase I trial of a 3-day topotecan Q 21 days for recurrent epithelial cancers of the ovary, fallopian tube, and peritoneum

OBJECTIVE

This trial was undertaken to determine the dose limiting toxicity (DLT) and maximum tolerated dose (MTD) of topotecan that can be administered for 3 days q 21 days. A 3-day schedule is more convenient and less expensive than standard 5-day dosing.

METHODS

Patients with recurrent epithelial ovary, tubal, or peritoneal carcinoma were treated with escalating doses of topotecan beginning at 2.50 mg/m(2) as an outpatient days 1-3 q 21 days. Colony stimulating factors were not employed prophylactically, but could be added for grade 4 marrow toxicity.

RESULTS

Twenty patients with a median age of 61 (range 46-80) and performance status of 0 or 1 were entered. All patients had received at least one prior paclitaxel/platinum regimen; 6 had received two. Ninety-one cycles were delivered (median = 6) and 98.9% were on schedule. Grade 4 neutropenia was seen in 17 of 20 patients (85%) in cycle 1 and in 38 of 91 (41.8%) total cycles. Sixteen of 20 patients (80%) started G-CSF on cycle 2. Two of 91 (2.2%) cycles had grade 4 thrombocytopenia. Four cycles (4.4%) were associated with febrile neutropenia. Two patients experienced grade 4 neurotoxicity (DLT) at 4.25 mg/m(2). Other nonhematologic toxicity was mild.

CONCLUSIONS

Topotecan can be safely administered on schedule as an outpatient days 1-3 q 21 days. Neurotoxicity was the DLT when G-CSF was added; the MTD was 3.75 mg/m(2). There was minimal other nonhematologic toxicity. Neutropenia was predictable and easily managed with G-CSF. Febrile neutropenia was uncommon and thrombocytopenia was rare at the doses evaluated.

Antisense oligonucleotides complementary to immunoglobulin sequences of BCL-2/immunoglobulin fusion transcript induce apoptosis of t(14;18) lymphoma cells

Antisense oligodeoxyribonucleotides directed at the bcl-2 translational start site downregulate bcl-2 and inhibit growth of the t(14;18)-positive lymphoma line WSU-FSCCL. Non-specific downregulation of bcl-2 expression is expected to be toxic to normal cells as well. The t(14;18) translocation results in a fusion transcript containing the entire bcl-2 coding sequence with a 3' breakpoint fused to the immunoglobulin J(H) region and the c mu heavy chain. We postulated that these immunoglobulin sequences would be a specific target for downregulation of the fusion gene. Here, we have demonstrated that antisense oligodeoxyribonucleotides targeted to immunoglobulin c(mu) sequences downregulate bcl-2 protein expression and induce apoptosis of WSU-FSCCL cells. Inhibiting growth of malignant cells by targeting non-oncogenic sequences other than breakpoints of fusion transcripts expands the potential for tumour-specific genetic manipulation.

Vinorelbine and estramustine in androgen-independent metastatic prostate cancer: a phase II study

BACKGROUND

The aim of this study was to determine the safety and activity of vinorelbine in combination with estramustine in men with androgen-independent metastatic prostate cancer.

METHODS

Twenty-five men with androgen-independent metastatic prostate cancer were treated with the combination of vinorelbine and estramustine. Vinorelbine 25 mg/m(2) was administered by intravenous bolus on Days 1 and 8. Estramustine 140 mg was administered three times a day by mouth on Days 1 through 14. Treatment was repeated every 21 days.

RESULTS

A total of 132 cycles of treatment were administered. The median number of cycles per patient was 5 (range: 1-16). Mild Grade 1 or 2 gastrointestinal toxicity and fatigue were the most common adverse effects. Hematologic toxicity was minimal. Treatment resulted in a sustained > 50% decrease in serum prostate-specific antigen (PSA) in 6 of 25 patients (24% of patients; 95% confidence interval (CI) 9-45%). The median duration of PSA response was 10 weeks (range: 3-39 weeks). Of the five men with bidimensionally measurable disease, none achieved a complete or partial response. There were no documented improvements in post-treatment bone scans. Median overall survival time was 14.1 months.

CONCLUSIONS

The combination of vinorelbine and estramustine is a well-tolerated and modestly active regimen in men with androgen-independent metastatic prostate cancer.

Differentiating large cell lymphoma from indolent small B-cell lymphoma in fine needle aspirates using p53, PCNA and transformed lymphocyte count

OBJECTIVE

To determine the usefulness of proliferating cell nuclear antigen (PCNA), p53 protein expression and transformed lymphocyte count (TLC) as adjunctive tests to differentiate indolent small B-cell lymphoma from large cell lymphoma in fine needle aspiration biopsies.

STUDY DESIGN

Aspirates of lymphoproliferative disorders from April 1993 to January 1997 were reviewed. The percentage of TLCs was determined on the Papanicolaou smear. The percentage and intensity of p53 and PCNA immunocytochemical staining was evaluated on cell block sections. These results were compared and correlated with the final diagnoses based on available morphology, flow cytometry and clinical history.

RESULTS

There were 40 cases of non-Hodgkin's lymphoma and 12 reactive lymph nodes. Adequate cell blocks were available on 16 large cell lymphomas, 7 grade 1-2 follicular center cell lymphomas, 6 mucosal associated lymphoid tissue lymphomas, 2 small lymphocytic lymphomas and 2 mantle cell lymphomas. Average TLC and p53 nuclear staining was highest in large cell lymphomas (57% TLC and 24% p53), followed by grades 1 and 2 follicular lymphomas (14% TLC and 15% p53) and lowest in other indolent lymphomas (< 10% TLC and < 1% p53). Average PCNA staining was highest in large cell lymphomas (46%) and lowest in small lymphocytic lymphomas (7%); however, TLC was the best parameter for differentiating large cell lymphoma from indolent small B-cell lymphoma.

CONCLUSION

TLC differentiated large cell lymphoma from indolent small B-cell lymphoma better than either p53 or PCNA alone or in combination. Significant overlap between categories limits usefulness of these immunocytochemical stains for differentiating these entities.

Using an MRI distortion transfer function to characterize the ghosts in motion-corrupted images

Motion artefact suppression remains an active topic in MRI. In this paper, we suggest that certain nonrigid, or spatially variant, characteristics of motion of an object can be represented by extending the work of Mitsa et al. This empirical extension uses a ghost distortion transfer function (GTDF) applied to the k-space (frequency domain) data. We demonstrate the variety of ghost characteristics that can be generated from various two-dimensional (2-D) GTDF's. The distortion transfer function for periodic motion along the Z-axis can be determined from the nonoverlapped portions of the ghost and central image. It required a GDTF with the shape of a belt bandpass filter to produce an image corresponding to the ghosts of a volunteer's abdomen image corrupted by unknown respiratory motion artefacts. The preliminary results of a composite method of motion artefact suppression are presented. The artefact suppression was successful for ghost images described by a GDTF have a low-pass nature, but less successful with ghosts have a GDTF of a bandpass nature.

A novel 50-kilodalton fragment of host cell factor 1 (C1) in G(0) cells

Host cell factor 1 (HCF-1; also called C1) is a 230-kDa protein which is cleaved posttranslationally into separate but associated N- and C-terminal polypeptides. These polypeptides are components of the C1 complex, along with Oct-1 and the viral protein VP16. The C1 complex is formed when herpes simplex virus (HSV) infects a cell and is responsible for transcription of the HSV immediate-early genes. A temperature-sensitive mutation in the N-terminal kelch domain of HCF-1 reversibly arrests cells in a G(0)-like state when grown at the nonpermissive temperature, and the same domain interacts with VP16 in the formation of the C1 complex. The form of HCF-1 in primary G(0) cells was investigated by using peripheral blood mononucleocytes and serum-arrested human primary fibroblasts. A novel 50-kDa N-terminal fragment of HCF-1 encompassing the kelch domain was identified in the cytoplasm of these cells. This fragment arises by proteolysis of the full-length HCF-1 protein and is able to associate with VP16.

Cellular association of glucosyltransferases in Leuconostoc mesenteroides and effects of detergent on cell association

Most glucosyltransferase (GTF) activity in sucrose-grown cultures of some strains of Leuconostoc mesenteroides is found with the cell pellet after centrifugation. GTFs are known to bind to dextrans, and it was traditionally assumed that cell-associated GTFs were bound to those dextrans that cosedimented with the cells. We used a mutant strain (LC-17), derived from strain NRRL B-1355, which produced dextransucrase in the absence of dextrans, to investigate the extent to which GTFs were bound to cells or dextrans. Much of the GTF activity in glucose-grown cultures of strain LC-17, which do not produce dextran, was located in the cell pellets. Soluble enzyme activity increased when cell suspensions from glucose- or sucrose-grown cultures were incubated with mild nonionic detergents or zwitterionic reagents. Alternansucrase produced by the parent strain B-1355 was almost entirely associated with cells under conditions in which dextrans were or were not produced. Alternansucrase, but not dextransucrase, tended to be enriched in the particulate fraction of B-1355 cells that had been broken in a French press. The distribution of alternansucrase and the effects of detergents on the distribution of GTFs suggest that soluble GTFs sequestered in the cytoplasm, and GTFs bound or adsorbed to the cell membrane are probably the major contributors to the cell-associated GTF activity.

Influence of ions on growth and production of exopolysaccharides by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772

Several lactic acid bacteria produce exopolysaccharides (EPS), either attached to the cell wall or excreted into the environment as slime material. EPS produced by Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus) and Streptococcus thermophilus play an important role in improving the texture and stability of yogurt and preventing syneresis (Cerning, 1990; Nakajima et al. 1990). The amount and composition of the EPS produced by lactic acid bacteria are dependent on a number of factors, such as temperature, initial pH, carbon source and the availability of minerals, vitamins and other medium components.

In previous work it was shown that the production and sugar composition of the EPS from Lb. bulgaricus NCFB2772 are affected by the carbohydrate source (Grobben et al. 1995, 1996). In a simplified defined medium, from which several vitamins and trace elements were omitted, EPS production by Lb. bulgaricus significantly increased, although growth of the strain was reduced (Grobben et al. 1998).

Glass needle-mediated microinjection of macromolecules and transgenes into primary human blood stem/progenitor cells

A novel glass needle-mediated microinjection method for delivery of macromolecules, including proteins and larger transgene DNAs, into the nuclei of blood stem/progenitor cells was developed. Temporary immobilization of cells to extracellular matrix-coated dishes has enabled rapid and consistent injection of macromolecules into nuclei of CD34(+), CD34(+)/CD38(-), and CD34(+)/CD38(-)/Thy-1(lo) human cord blood cells. Immobilization and detachment protocols were identified, which had no adverse effect on cell survival, progenitor cell function (colony forming ability), or stem cell function (NOD/SCID reconstituting ability). Delivery of fluorescent dextrans to stem/progenitor cells was achieved with 52% +/- 8.4% of CD34(+) cells and 42% +/- 14% of CD34(+)/CD38(-)cells still fluorescent 48 hours after injection. Single-cell transfer and culture of injected cells has demonstrated long-term survival and proliferation of CD34(+) and CD34(+)/CD38(-) cells, and retention of the ability of CD34(+)/CD38(-) cells to generate progenitor cells. Delivery of DNA constructs (currently </= 19.6 kb) and fluorescently labeled proteins into CD34(+) and CD34(+)/CD38(-) cells was achieved with transient expression of green fluorescent protein observed in up to 75% of injected cells. These data indicate that glass needle-mediated delivery of macromolecules into primitive hematopoietic cells is a valuable method for studies of stem cell biology and a promising method for human blood stem cell gene therapy. (Blood. 2000;95:437-444)