Leflunomide Confers Rapid Recovery from COVID-19 and is Coupled with Temporal Immunologic Changes

Background: Vaccines for SARS-CoV-2 have been considerably effective in reducing rates of infection and severe COVID-19. However, many patients, especially those who are immunocompromised due to cancer or other factors, as well as individuals who are unable to receive vaccines or are in resource-poor countries, will continue to be at risk for COVID-19. We describe clinical, therapeutic, and immunologic correlatives in two patients with cancer and severe COVID-19 who were treated with leflunomide after failing to respond to standard-of-care comprising remdesivir and dexamethasone. Both patients had breast cancer and were on therapy for the malignancy. Methods: The protocol is designed with the primary objective to assess the safety and tolerability of leflunomide in treating severe COVID-19 in patients with cancer. Leflunomide dosing consisted of a loading dose of 100 mg daily for the first three days, followed by daily dosing, at the assigned dose level (Dose Level 1: 40 mg, Dose Level -1, 20 mg; Dose Level 2, 60 mg), for an additional 11 days. At defined intervals, serial monitoring of blood samples for toxicity, pharmacokinetics, and immunologic correlative studies were performed, as well as nasopharyngeal swabs for PCR analysis of SARS-CoV-2. Results: Preclinically, leflunomide impaired viral RNA replication, and clinically, it led to a rapid improvement in the two patients discussed herein. Both patients completely recovered, with minimal toxicities; all adverse events experienced were considered unrelated to leflunomide. Single-cell mass-cytometry analysis showed that leflunomide increased levels of CD8+ cytotoxic and terminal effector T cells and decreased naïve and memory B cells. Conclusions: With ongoing COVID-19 transmission and occurrence of breakthrough infections in vaccinated individuals, including patients with cancer, therapeutic agents that target both the virus and host inflammatory response would be helpful despite the availability of currently approved anti-viral agents. Furthermore, from an access to care perspective, especially in resource-limited areas, an inexpensive, readily available, effective drug with existing safety data in humans is relevant in the real-world setting.

Investigating possible impact, and interaction, of phytase supplementation during pre-experimental and experimental phases on assay of true phosphorus pre-caecal digestibility and total tract retention

1. Two experiments were conducted to investigate whether the use of phytase in the pre-experimental or experimental phases of true pre-caecal phosphorus digestibility (TPD) assay influenced the assayed TPD values. In experiments 1 and 2, broiler chickens were randomly allocated to 12 treatments in a 2 × 2 × 3 factorial arrangement. The factors were pre-experimental phytase supplementation (+ or -), experimental phase phytase supplementation (+ or -) with varying soybean meal inclusion levels (450, 560, or 670 g/kg).2. The diets in the pre-experimental phase were based on maize-soybean meal, whereas the diet used during the experimental phase was semi-purified, with soybean meal as the only source of P. Both TPD and true phosphorus retention (TPR) were determined using regression for the P output (g/kg, dry matter basis), pre-caecal or total tract, against P intake (g/kg). Data for TPD and TPR were analysed as a 2 × 2 factorial (with or without pre-experimental or experimental phase phytase).3. In both experiments 1 and 2, there were no significant effects for pre-experimental phytase supplementation nor interaction of pre- and experimental phytase supplementation on any of the pre-caecal digestibility responses. Phytase supplementation during the experimental phase increased (P < 0.01) pre-caecal P digestibility and retention, as well as digestible and retained P intake, and decreased (P < 0.01) P output.4. In experiment 1, pre- and experimental phytase supplementation increased (P < 0.01) the coefficient of TPR. In experiment 2, there was no significant effect of pre-experimental phytase supplementation on coefficient of pre-caecal TPD. However, phytase supplementation in the experimental phase increased (P < 0.01) the coefficient of pre-caecal TPD.5. In conclusion, whether or not phytase was supplemented to a P-adequate diet in the pre-experimental phase of the TPD assay, it had no influence on assayed TPD or TPR value.

Total Marrow and Lymphoid Irradiation with Post-Transplantation Cyclophosphamide for Patients with AML in Remission

Graft-versus-host disease (GVHD) has remained the main cause of post-transplantation mortality and morbidity after allogeneic hematopoietic cell transplantation (alloHCT), adding significant economic burden and affecting quality of life. It would be desirable to reduce the rate of GVHD among patients in complete remission (CR) without increasing the risk of relapse. In this study, we have tested a novel conditioning regimen of total marrow and lymphoid irradiation (TMLI) at 2000 cGy, together with post-transplantation cyclophosphamide (PTCy) for patients with acute myeloid leukemia in first or second CR, to attenuate the risk of chronic GVHD by using PTCy, while using escalated targeted radiation conditioning before allografting to offset the possible increased risk of relapse. The primary objective was to evaluate the safety/feasibility of combining a TMLI transplantation conditioning regimen with a PTCy-based GVHD prophylaxis strategy, through the assessment of adverse events in terms of type, frequency, severity, attribution, time course, duration, and complications, including acute GVHD, infection, and delayed neutrophil/platelet engraftment. Secondary objectives included estimation of non-relapse mortality (NRM), overall survival (OS), relapse-free survival, acute and chronic GVHD, and GVHD-relapse-free survival (GRFS). A patient safety lead-in was first conducted to ensure there were no unexpected toxicities and was expanded on the basis of lack of dose-limiting toxicities. The patient safety lead-in segment followed 3 + 3 dose expansion/(de-)escalation rules based on observed toxicity through day 30; the starting dose of TMLI was 2000 cGy, and a de-escalation to 1800 cGy was considered. After the safety lead-in segment, an expansion cohort of up to 12 additional patients was to be studied. TMLI was administered on days -4 to 0, delivered in 200 cGy fractions twice daily. The radiation dose delivered to the liver and brain was kept at 1200 cGy. Cyclophosphamide was given on days 3 and 4 after alloHCT, 50 mg/kg each day for GVHD prevention; tacrolimus was given until day 90 and then tapered. Among 18 patients with a median age of 40 years (range 19-56), the highest grade toxicities were grade 2 Bearman bladder toxicity and stomatitis. No grade 3 or 4 Bearman toxicities or toxicity-related deaths were observed. The cumulative incidence of acute GVHD grade 2 to 4 and moderate-to-severe chronic GVHD were 11.1% and 11.9%, respectively. At a median follow up of 24.5 months, two-year estimates of OS and relapse-free survival were 86.7% and 83.3%, respectively. Disease relapse at 2 years was 16.7%. The estimates of NRM at 2 years was 0%. The GVHD/GRFS rate at 2 years was 59.3% (95% confidence interval, 28.8-80.3). This chemotherapy-free conditioning regimen, together with PTCy and tacrolimus, is safe, with no NRM. Preliminary results suggest an improved GRFS rate.

Germline ATM variants predispose to melanoma: a joint analysis across the GenoMEL and MelaNostrum consortia

PURPOSE

Ataxia-Telangiectasia Mutated (ATM) has been implicated in the risk of several cancers, but establishing a causal relationship is often challenging. Although ATM single-nucleotide polymorphisms have been linked to melanoma, few functional alleles have been identified. Therefore, ATM impact on melanoma predisposition is unclear.

METHODS

From 22 American, Australian, and European sites, we collected 2,104 familial, multiple primary (MPM), and sporadic melanoma cases who underwent ATM genotyping via panel, exome, or genome sequencing, and compared the allele frequency (AF) of selected ATM variants classified as loss-of-function (LOF) and variants of uncertain significance (VUS) between this cohort and the gnomAD non-Finnish European (NFE) data set.

RESULTS

LOF variants were more represented in our study cohort than in gnomAD NFE, both in all (AF = 0.005 and 0.002, OR = 2.6, 95% CI = 1.56-4.11, p < 0.01), and familial + MPM cases (AF = 0.0054 and 0.002, OR = 2.97, p < 0.01). Similarly, VUS were enriched in all (AF = 0.046 and 0.033, OR = 1.41, 95% CI = 1.6-5.09, p < 0.01) and familial + MPM cases (AF = 0.053 and 0.033, OR = 1.63, p < 0.01). In a case-control comparison of two centers that provided 1,446 controls, LOF and VUS were enriched in familial + MPM cases (p = 0.027, p = 0.018).

CONCLUSION

This study, describing the largest multicenter melanoma cohort investigated for ATM germline variants, supports the role of ATM as a melanoma predisposition gene, with LOF variants suggesting a moderate-risk.

Reactivation of human herpesvirus 6 in pediatric allogeneic hematopoietic stem cell transplant recipients

BACKGROUND

Reactivation of human herpesvirus 6 (HHV-6) occurs in 30%-50% of patients (pts) who receive allogeneic (allo) hematopoietic stem cell transplant (HCT). However, the recommendation for post-transplant HHV-6 monitoring and treatment in pediatric pts is not well established.

METHODS

HHV-6 incidence rates and the clinical outcomes were reported for 139 pediatric pts (≤18 years) undergoing first allo-HCT at City of Hope from July 2011 to July 2017, for whom HHV-6 was monitored weekly throughout HCT hospitalization. For 57 pediatric pts, who underwent first HCT from January 2009 to July 2011, HHV-6 was tested as clinically indicated and only rates of HHV-6 viremia were collected.

RESULTS

From July 2011 to July 2017, HHV-6 was detected in 88/139 pts (63%). The frequency of HHV-6 viremia was associated with malignant diagnoses, myeloablative conditioning, and cord blood HCT. Treatment with antiviral agents was offered to symptomatic pts with a higher viral load (VL), for whom the time to VL clearance was longer and the frequency of subsequent recurrences was higher. Pts with a lower VL cleared HHV-6 without treatment. HHV-6 viremia was associated with a higher frequency of grade II-IV acute graft-versus-host disease (GVHD) (P = .022), but did not affect overall survival (OS), disease-free survival (DFS), non-relapsed mortality (NRM), myeloid, or platelet (Plt) engraftment.

CONCLUSIONS

HHV-6 weekly screening is not necessary for all HCT pts but may be considered for high-risk pts with malignant diagnoses undergoing cord blood HCT; otherwise, HHV-6 should be tested as clinically indicated. Only symptomatic pts (especially with a high VL > 25 000) could benefit from treatment. HHV-6 viremia at the time of initiation and administration of the conditioning regimen cleared promptly without the need to augment the transplant process.

Multi-center phase II trial of bortezomib and rituximab maintenance combination therapy in patients with mantle cell lymphoma after consolidative autologous stem cell transplantation

Background

Mantle cell lymphoma (MCL) is an aggressive and incurable lymphoma. Standard of care for younger patients with MCL is induction chemotherapy followed by autologous stem cell transplantation (auto-HCT). Rituximab maintenance after auto-HCT has been shown to improve progression-free survival (PFS) and overall survival (OS) in MCL. Bortezomib maintenance therapy has also been shown to be tolerable and feasible in this setting. However, the combination of bortezomib and rituximab as maintenance therapy post-auto-HCT has not been studied.

Methods

We conducted a multicenter, phase II trial of bortezomib given in combination with rituximab as maintenance in MCL patients after consolidative auto-HCT. Enrolled patients (n = 23) received bortezomib 1.3 mg/m² subcutaneously weekly for 4 weeks every 3 months (up to 24 months) and rituximab 375 mg/m² intravenously weekly for 4 weeks every 6 months (up to 24 months) for a total duration of 2 years. The primary study endpoint was disease-free survival (DFS).

Results

With a median follow-up of 35.9 months, the 2-year DFS probability was 90.2% (95% CI 66–97), and 2-year OS was 94.7% (95% CI 68–99). The most frequent grade 3/4 toxic events were neutropenia (in 74% of patients) and lymphopenia (in 35%). The incidence of peripheral neuropathy was 48% for grade 1, 9% for grade 2, and 0% for grade 3/4. We also examined the role of quantitative cyclin D1 (CCND1) mRNA in monitoring minimal residual disease.

Conclusion

Combined bortezomib and rituximab as maintenance therapy in MCL patients following auto-HCT is an active and well-tolerated regimen.

Trial registration

ClinicalTrials.govNCT01267812, registered Dec 29, 2010.

Phase I/II trial of the oral regimen ixazomib, pomalidomide, and dexamethasone in relapsed/refractory multiple myeloma

In this phase I/II trial, a triplet regimen of ixazomib (Ixa: 3 or 4 mg), pomalidomide (Pom: 4 mg), and dexamethasone (Dex: 40 mg) was administered to 32 lenalidomide-refractory multiple myeloma (MM) patients; 31 were evaluable for response and toxicity. At dose level 1 (DL1, 3 mg Ixa), 1/3 patients experienced grade 3 fatigue, grade 3 lung infection, grade 4 neutropenia, and grade 4 thrombocytopenia; all were considered dose-limiting. Per 3 + 3 phase I design, an additional three patients were enrolled to DL1, with no further dose-limiting toxicity (DLT). At dose level 2 (DL2, 4 mg Ixa), 1/3 patients had dose-limiting febrile neutropenia, neutropenia, and thrombocytopenia (grade 4 each). DL2 was expanded to enroll three additional patients with no further DLT, establishing the recommended phase II dose (RP2D). In phase II, 19 additional patients were treated at RP2D. With a median follow-up of 11.9 months, 48% achieved  ≥ partial response (PR), with 5 patients (20%) achieving very good partial response (VGPR) and 76% experiencing ≥ stable disease. The most common adverse events (≥grade 2) were anemia, neutropenia, thrombocytopenia, and infections. Peripheral neuropathy was infrequent. In summary, Ixa/Pom/Dex is a well-tolerated and effective oral combination therapy for patients with relapsed/refractory MM.

Relapsed or Refractory Double-Expressor and Double-Hit Lymphomas Have Inferior Progression-Free Survival After Autologous Stem-Cell Transplantation

Purpose Double-hit lymphomas (DHLs) and double-expressor lymphomas (DELs) are subtypes of diffuse large B-cell lymphoma (DLBCL) associated with poor outcomes after standard chemoimmunotherapy. Data are limited regarding outcomes of patients with relapsed or refractory (rel/ref) DEL or DHL who undergo autologous stem-cell transplantation (ASCT). We retrospectively studied the prognostic impact of DEL and DHL status on ASCT outcomes in patients with rel/ref DLBCL. Methods Patients with chemotherapy-sensitive rel/ref DLBCL who underwent ASCT at two institutions and in whom archival tumor material was available were enrolled. Immunohistochemistry for MYC, BCL2, and BCL6 and fluorescence in situ hybridization (FISH) for MYC were performed. In cases with MYC rearrangement or copy gain, FISH for BCL2 and BCL6 was also performed. Results A total of 117 patients were included; 44% had DEL and 10% had DHL. DEL and DHL were associated with inferior progression-free survival (PFS), and DHL was associated with poorer overall survival (OS). The 4-year PFS in patients with DEL compared with those with non-DEL was 48% versus 59% ( P = .049), and the 4-year OS was 56% versus 67% ( P = .10); 4-year PFS in patients with DHL compared with those with non-DHL was 28% versus 57% ( P = .013), and 4-year OS was 25% versus 61% ( P = .002). The few patients with concurrent DEL and DHL had a poor outcome (4-year PFS, 0%). In multivariable models, DEL and DHL were independently associated with inferior PFS, whereas DHL and partial response ( v complete response) at transplant were associated with inferior OS. Conclusion DEL and DHL are both associated with inferior outcomes after ASCT in patients with rel/ref DLBCL. Although ASCT remains a potentially curative approach, these patients, particularly those with DHL, are a high-risk subset who should be targeted for investigational strategies other than standard ASCT.

Influence of Absorption, Distribution, Metabolism, and Excretion Genomic Variants on Tacrolimus/Sirolimus Blood Levels and Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation

Allelic variants of genes implicated in drug absorption, distribution, metabolism, and excretion (ADME) determine the pharmacokinetic variability of many medications and are increasingly recognized as important factors determining the success or failure of medical treatments. Both tacrolimus and sirolimus have narrow therapeutic ranges maintained by therapeutic drug monitoring (TDM). Using an ADME panel that covers >99% of the PharmaADME working group core list (188 single nucleotide polymorphism [SNP] and 12 copy number variant [CNV] assays in 36 pharmacogenetically relevant genes), we studied 177 patients who underwent allogeneic hematopoietic cell transplantation (HCT) using tacrolimus/sirolimus-based graft-versus-host disease (GVHD) prophylaxis. We tested for possible associations between ADME variants and tacrolimus/sirolimus drug levels, concentration/dose (C/D) ratio, and clinical endpoints, including acute GVHD. A total of 62 SNP and 6 CNV assays were evaluable after removing the variants, which were homozygous in (nearly) all samples. For sirolimus, rs2032582 (ABCB1) T-carriers versus non-T-carriers were associated with higher blood levels (P = .01), with similar results for C/D ratio. Generalized estimating equation analysis supported these findings. For tacrolimus, rs776746 CYP3A5*3/*3 and CYP3A5*3/*1 were associated with higher blood levels than CYP3A5*1/*1 (P = .002). By multivariable analysis, rs776746 CYP3A5*3/*3 and CYP3A5*3/*1 were independently associated with decreased acute GVHD compared with CYP3A5*1/*1, after adjustment for conditioning, donor type, race/ethnicity, and age. We demonstrated association of specific ADME genetic polymorphisms with blood levels of tacrolimus/sirolimus, and incidence of acute GVHD after HCT, in spite of TDM and dose adjustment. A larger ongoing study will determine whether these associations have clinical utility beyond TDM.

Results of a Multicenter Phase II Trial of Brentuximab Vedotin as Second-Line Therapy before Autologous Transplantation in Relapsed/Refractory Hodgkin Lymphoma

This multicenter prospective phase II study examines the activity and tolerability of brentuximab vedotin as second-line therapy in patients with Hodgkin lymphoma that was relapsed or refractory after induction therapy. Brentuximab vedotin (1.8 mg/kg) was administered i.v. on day 1 of a 21-day cycle for a total of 4 cycles. Patients then proceeded to autologous hematopoietic cell transplantation (AHCT), if eligible, with or without additional salvage therapy, based on remission status after brentuximab vedotin. The primary endpoint was overall response rate (ORR). Secondary endpoints were safety, stem cell mobilization/collection, AHCT outcomes, and association of CD68(+) with outcomes. Of 37 patients, the ORR was 68% (13 complete remission, 12 partial remission). The regimen was well tolerated with few grade 3/4 adverse events, including lymphopenia (1), neutropenia (3), rash (2), and hyperuricemia (1). Thirty-two patients (86%) were able to proceed to AHCT, with 24 patients (65%) in complete remission at time of AHCT. Thirteen patients in complete remission, 4 in partial remission, and 1 with stable disease (49%) received AHCT without salvage combination chemotherapy. CD68 expression did not correlate with response to brentuximab vedotin. The median number of stem cells mobilized was 6.0 × 10(6) (range, 2.6 to 34), and median number of days to obtain minimum collection (2 × 10(6)) was 2 (range, 1 to 6). Brentuximab vedotin as second-line therapy is active, well tolerated, and allows adequate stem cell collection and engraftment. For Hodgkin lymphoma patients with relapsed/refractory disease after induction therapy, second-line brentuximab vedotin, followed by combination chemotherapy for residual disease, can effectively bridge patients to AHCT.

Survival outcomes in patients with multiple primary melanomas

BACKGROUND

A substantial number of melanoma patients will develop multiple primary melanomas (MPM). Currently, little is known about the impact of MPM on survival.

OBJECTIVE

We aimed to determine whether melanoma survival is worse for patients with MPM compared to those with a single invasive primary melanoma (SPM).

MATERIALS AND METHODS

A cohort study was conducted. Patients were sourced from an Australian population, with follow-up information collected retrospectively from registry data. Melanoma-specific survival analysis was performed to find associated variables after adjustment for known prognostic factors, using four different models, each selecting a different index melanoma lesion.

RESULTS

1068 stage I and II melanoma patients were followed up for a median of 24.4 years. MPM was found in 17.8% of the cohort (190 patients), more likely among males and older age groups. Other clinicopathological parameters were similar between the MPM and SPM (878 patients) cohorts. After adjustment for age, sex and Breslow thickness, MPM was a hazard for death from melanoma, across all models, reaching significance when considering the last invasive lesion as the index melanoma (HR = 2.76, P = 0.017).

CONCLUSION

Patients with multiple invasive lesions seem more at risk of death from melanoma, independent of known prognostic factors.

Impact of Additional Cytogenetic Abnormalities in Adults with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia Undergoing Allogeneic Hematopoietic Cell Transplantation

The occurrence of additional cytogenetic abnormalities (ACAs) is common in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) but is of unknown significance in the tyrosine kinase inhibitor (TKI) era. We retrospectively analyzed data from a consecutive case series of adults with Ph+ ALL who had undergone allogeneic hematopoietic cell transplantation (alloHCT) at City of Hope between 2003 and 2014. Among 130 adults with Ph+ ALL who had TKI therapy before alloHCT, 78 patients had available data on conventional cytogenetics at diagnosis and were eligible for outcomes analysis. ACAs were observed in 41 patients (53%). There were no statistically significant differences in median age, median initial WBC count, post-HCT TKI maintenance, or disease status at the time of transplant between the Ph-only and ACA cohorts; however, the Ph-only cohort had a higher rate of minimal residual disease positivity at the time of HCT. Three-year leukemia-free survival (79.8% versus 39.5%, P = .01) and 3-year overall survival (83% versus 45.6%, P = .02) were superior in the Ph-only cohort compared with the ACA cohort, respectively. Monosomy 7 was the most common additional aberration observed in our ACA cohort (n = 12). Thus, when TKI therapy and alloHCT are used as part of adult Ph+ ALL therapy, the presence of ACAs appears to have a significant deleterious effect on outcomes post-HCT.

Brentuximab vedotin is associated with improved progression-free survival after allogeneic transplantation for Hodgkin lymphoma

We previously reported that brentuximab vedotin (BV) enabled successful reduced-intensity allogeneic hematopoietic cell transplantation (RIC-alloHCT) in patients with relapsed Hodgkin lymphoma, after a median follow-up of 14.4 months. We now provide an updated report on 21 patients who were treated from 2009 to 2012 with BV before RIC-alloHCT with a uniform fludarabine/melphalan conditioning regimen and donor source after a median follow-up of 29.9 months. We have also retrospectively compared the patient characteristics and outcomes of these BV-pretreated patients to 23 patients who received fludarabine/melphalan RIC-alloHCT without prior BV, in the time period before the drug was available (2003 to 2009). Patients who were treated with BV before RIC-alloHCT had a lower median hematopoietic cell transplantation-specific comorbidity index and a reduced number of peri-transplantation toxicities. There were also improvements in 2-year progression-free survival (59.3% versus 26.1%) and cumulative incidence of relapse/progression (23.8% versus 56.5%).

Chemical communication in the dacetine antDaceton armigerum (Hymenoptera: Formicidae)

Contrary to previous assumptions,Daceton armigerum, the largest ant in the myrmicine tribe Dacetini, employs trail communication. We identified two anatomical sources of trail pheromones: Trails drawn with poison gland contents can last for more than seven days. Trails drawn with the newly discovered sternal glands (in the VIth and VIIth abdominal sternites) are effective but relatively short-lived. In addition, our bioassays revealed that the contents of the mandibular glands elicit alarm behavior, and secretions from the pygidial gland release attraction. When tested with artificial poison gland trails from seven other myrmicine species,Daceton did not exhibit trail following behavior. We confirmed, however, previous findings thatAtta respond toDaceton poison gland trails andSolenopsis followDaceton Dufour's gland trails.

Quality of bevacizumab compounded for intravitreal administration

AIM

To compare the quality and stability of unlicensed, repackaged bevacizumab intended for intravitreal injection, as provided by five licensed compounding pharmacies in the United Kingdom, with bevacizumab in its original glass vial.

METHODS

Repackaged bevacizumab was obtained from five UK suppliers. Samples were analyzed at two time points (day 1 and day 14). Microflow imaging was performed to evaluate subvisible particle size, particle density, and particle size distribution. Protein concentration, immunoglobulin G (IgG) content, and molecular weight were also determined.

RESULTS

A significant difference in subvisible particle density was observed between bevacizumab batches from the five suppliers on day 1 (P<0.001). An increase in subvisible particle density was observed between day 1 and 14 for repackaged bevacizumab from all suppliers (all P<0.05), but not the reference compound. Protein concentration, IgG content, and molecular weight were comparable between batches from each supplier and the reference bevacizumab.

DISCUSSION

The study results indicate that the quality of bevacizumab repackaged into prefilled plastic syringes is variable among the different compounding pharmacies in the United Kingdom. Furthermore, particle density may increase with storage in repackaged syringes. It is noteworthy that particle size distribution in both the repackaged and reference bevacizumab fell outside of the range specified by the United States Pharmacopeia for injectable ophthalmic solutions. These data highlight the need for further research into the use of unlicensed, repackaged bevacizumab intended for intravitreal injection.

Modulation of gastrointestinal function by MuDelta, a mixed µ opioid receptor agonist/ µ opioid receptor antagonist

BACKGROUND & PURPOSE

Loperamide is a selective µ opioid receptor agonist acting locally in the gastrointestinal (GI) tract as an effective anti-diarrhoeal but can cause constipation. We tested whether modulating µ opioid receptor agonism with δ opioid receptor antagonism, by combining reference compounds or using a novel compound ('MuDelta'), could normalize GI motility without constipation.

EXPERIMENTAL APPROACH

MuDelta was characterized in vitro as a potent µ opioid receptor agonist and high-affinity δ opioid receptor antagonist. Reference compounds, MuDelta and loperamide were assessed in the following ex vivo and in vivo experiments: guinea pig intestinal smooth muscle contractility, mouse intestinal epithelial ion transport and upper GI tract transit, entire GI transit or faecal output in novel environment stressed mice, or four weeks after intracolonic mustard oil (post-inflammatory). Colonic δ opioid receptor immunoreactivity was quantified.

KEY RESULTS

δ Opioid receptor antagonism opposed µ opioid receptor agonist inhibition of intestinal contractility and motility. MuDelta reduced intestinal contractility and inhibited neurogenically-mediated secretion. Very low plasma levels of MuDelta were detected after oral administration. Stress up-regulated δ opioid receptor expression in colonic epithelial cells. In stressed mice, MuDelta normalized GI transit and faecal output to control levels over a wide dose range, whereas loperamide had a narrow dose range. MuDelta and loperamide reduced upper GI transit in the post-inflammatory model.

CONCLUSIONS AND IMPLICATIONS

MuDelta normalizes, but does not prevent, perturbed GI transit over a wide dose-range in mice. These data support the subsequent assessment of MuDelta in a clinical phase II trial in patients with diarrhoea-predominant irritable bowel syndrome.

Reduced intensity allogeneic hematopoietic stem cell transplantation for MDS using tacrolimus/sirolimus-based GVHD prophylaxis

We report a consecutive series of 59 patients with MDS who underwent reduced-intensity hematopoietic stem cell transplantation (RI-HSCT) with fludarabine/melphalan conditioning and tacrolimus/sirolimus-based GVHD prophylaxis. Two-year OS, EFS, and relapse incidences were 75.1%, 65.2%, and 20.9%, respectively. The cumulative incidence of non-relapse mortality at 100 days, 1 year, and 2 years was 3.4%, 8.5%, and 10.5%, respectively. The incidence of grade II-IV acute GVHD was 35.4%; grade III-IV was 18.6%. Forty of 55 evaluable patients developed chronic GVHD; of these 35 were extensive grade. This RI-HSCT protocol produces encouraging outcomes in MDS patients, and tacrolimus/sirolimus-based GVHD prophylaxis may contribute to that promising result.

Matched-cohort analysis of autologous hematopoietic cell transplantation with radioimmunotherapy versus total body irradiation-based conditioning for poor-risk diffuse large cell lymphoma

We conducted a matched-cohort analysis of autologous transplant conditioning regimens for diffuse large cell lymphoma in 92 patients treated with either radioimmunotherapy (RIT) or total body irradiation (TBI)-based conditioning regimens. The RIT regimen consisted of 0.4 mCi/kg of (90)Y-ibritumomab tiuxetan plus BEAM (BCNU, etoposide, cytarabine, melphalan). The TBI-based regimen combined fractionated TBI at 1200 cGy, with etoposide and cyclophosphamide. Five factors were matched between 46 patient pairs: age at transplant ±5 years, disease status at salvage, number of prior regimens, year of diagnosis ±5 years, and year of transplantation ±5 years. Patients in the TBI group had higher rates of cardiac toxicity and mucositis, whereas Z-BEAM patients had a higher incidence of pulmonary toxicity. Overall survival at 4 years was 81.0% for the Z-BEAM and 52.7% for the TBI group (P = .01). The 4-year cumulative incidence of relapse/progression was 40.4% and 42.1% for Z-BEAM and TBI, respectively (P = .63). Nonrelapse mortality was superior in the Z-BEAM group: 0% compared with 15.8% for TBI at 4 years (P < .01). Our data demonstrate that RIT-based conditioning had a similar relapse incidence to TBI, with lower toxicity, resulting in improved overall survival, particularly in patients with ≥2 prior regimens.

Allogeneic hematopoietic cell transplant for peripheral T-cell non-Hodgkin lymphoma results in long-term disease control

The study analyzed outcomes of a consecutive case series of 37 patients with peripheral T-cell non-Hodgkin lymphoma, from related and unrelated donors, using allogeneic hematopoietic cell transplant (allo-HCT), between the years 2000 and 2007. All patients were pretreated; the majority had either relapsed or progressive disease (n = 25, 68%), 13 had cutaneous histologies (CTCL), and all were ineligible for autologous transplant. Fully ablative conditioning regimens were used in 13 patients while 24 patients underwent reduced intensity conditioning (RIC). At 5 years the overall survival (OS) and progression-free survival (PFS) probabilities were 52.2% and 46.5%, respectively. At the time of analysis, nine (24.3%) patients had either relapsed (n = 6) or progressed (n = 3) post allo-HCT. The cumulative incidences of relapse/progression and non-relapse mortality at 5 years were 24.3% and 28.9%. No statistically significant variables for survival or relapse were discovered by univariate Cox regression analysis of disease and patient characteristics; differences between CTCL and other histologies were not significant. The median follow-up of 64.0 months (range: 16.4-100.4) indicates a mature data-set with probable cure in the survivors. The relapse/progression curves reached and maintained plateaus after 1 year post-transplant, demonstrating that long-term disease control is possible after allo-HCT in patients with peripheral T-cell lymphoma with advanced disease.

High-dose therapy and autologous hematopoietic cell transplantation in peripheral T cell lymphoma (PTCL): analysis of prognostic factors

Patients with peripheral T cell lymphoma (PTCL) have a poor prognosis with current treatment approaches. We examined the outcomes of high-dose therapy (HDT) and autologous hematopoietic cell transplant (AHCT) on the treatment of PTCL and the impact of patient/disease features on long-term outcome. Sixty-seven patients with PTCL-not otherwise specified (n = 30), anaplastic large cell lymphoma (n = 30), and angioimmunoblastic T cell lymphoma (n = 7) underwent HDT/AHCT at the City of Hope. The median age was 48 years (range: 5-78). Twelve were transplanted in first complete remission (1CR)/partial remission (PR) and 55 with relapsed or induction failure disease (RL/IF). With a median follow-up for surviving patients of 65.8 months (range: 24.5-216.0) the 5-year overall survival (OS) and progression-free survival (PFS) were 54% and 40%, respectively. The 5-year PFS was 75% for 1CR/PR compared to 32% for RL/IF patients (P = .01). When the Prognostic Index for PTCL unspecified (PIT) was applied at the time of transplant, patients in the PIT 3-4 group had 5-year PFS of only 8%. These results show that HDT/AHCT can improve long-term disease control in relapsed/refractory PTCL and that HDT/AHCT should ideally be applied either during 1CR/PR, or as part of upfront treatment. More effective and novel therapies are needed for patients with high-risk disease (PIT 3-4 factors) and allogeneic HCT should be explored in these patients.

Reduced intensity allogeneic hematopoietic cell transplantation can induce durable remission in heavily pretreated relapsed Hodgkin lymphoma

Hodgkin lymphoma (HL) can be aggressive and intractable in some cases. Patients who relapse after autologous HCT (auto-HCT) have limited treatment options. City of Hope reports our experience in the use of reduced intensity allogeneic hematopoietic cell transplantation (allo-HCT) in 24 heavily pretreated patients with relapsed HL, between January 2003 and December 2008. The median number of prior therapies was 5; 20/24 patients had prior auto-HCT. The conditioning regimen for all patients was fludarabine and melphalan. With a median follow-up for living patients of 39.0 months, at 2 years the overall survival (OS) was 60% (95% CI 42, 72) and the progression-free survival was 27% (95% CI 22, 32). Non-relapse mortality was 13.1% (95% CI 5.1, 31.4) at 2 years. The incidence of grade II-IV aGVHD was 45.8% and 8.3% for grade III-IV. Allo-HCT in heavily pretreated relapsed Hodgkin lymphoma is feasible, tolerable, and can induce durable clinical remissions.

HIV status does not affect the outcome of autologous stem cell transplantation (ASCT) for non-Hodgkin lymphoma (NHL)

Randomized trials comparing autologous stem cell transplant (ASCT) to conventional chemotherapy have demonstrated superior survival among HIV-negative ASCT patients with relapsed non-Hodgkin lymphoma (NHL). Recent trials explored the feasibility of ASCT in the HIV setting. Although these studies have shown that ASCT in HIV-positive NHL patients (HIVpos-NHL) is well tolerated, the impact of HIV infection on long-term transplant outcome is not well characterized. Ongoing comparison of long-term survival following ASCT in HIVpos-NHL patients and HIVneg-NHL patients will allow investigators to explore whether there should be inclusion of HIVpos-NHL patients in ASCT trials. To study long-term outcome we conducted a single-institution matched case-controlled study in HIVpos-NHL patients (cases) and HIVneg-NHL patients (controls). Twenty-nine patients with HIVpos-NHL were matched with HIVneg-NHL controls on sex, time to ASCT, year of transplant, histology, age, disease status, number prior regimens, and conditioning regimen. Nonrelapse mortality (NRM) was similar: 11% (95% confidence interval [CI]: 4%-28%) in HIVpos-NHL patients and 4% (95% CI: 1%-25%) in HIVneg-NHL controls (P = .18). Two-year disease-free survival (DFS) for the HIVpos-NHL patients was 76% (95% CI: 62%-85%) and 56% (95% CI: 45%-66%) for the HIVneg-NHL controls (P = .33). Overall survival was also similar; the 2-year point estimates were 75% (95% CI: 61%-85%) and 75% (95% CI: 60%-85%), respectively (P = .93), despite inclusion of more poor risk HIVpos-NHL patients. These results provide further evidence that HIV status does not affect the long-term outcome of ASCT for NHL, and therefore HIV status alone should no longer exclude these patients from transplant clinical trials.

Prokineticin-1 evokes secretory and contractile activity in rat small intestine

BACKGROUND

Prokineticins 1 and 2 (PROK1 and PROK2) are so named because they contract gastrointestinal smooth muscle, yet little else is known about their role in gastrointestinal function. Therefore, we used a combination of approaches to elucidate the mechanisms by which PROK1 alters ileal contractility and secretion in rats.

METHODS

RT-PCR and immunofluorescence were used to determine PROK and receptor (PK-R) mRNA levels and PK-R1 localization, respectively. Upper GI transit and fluid secretion were determined in vivo. Contractility and intestinal epithelial ion transport were assessed in isolated ileal segments.

KEY RESULTS

In the gastric fundus, PROK1 mRNA is highly expressed (70-fold >PROK2 mRNA) whereas the ileum has the highest mRNA expression of its receptor. PK-R1 immunoreactivity is visualized in ileal crypt cells, and in submucosal and myenteric neurons. In ileal segments, PROK1 evokes biphasic contractile responses consisting of an early, TTX-sensitive response (EC(50) = 87.8 nmol L(-1)) followed by a late, TTX-insensitive (EC(50) = 72.4 nmol L(-1)) component that is abolished in mucosa-free preparations. Oral administration of PROK1 enhances small bowel transit (111 +/- 3% of control) and fluid secretion (340 +/- 90% of control) and in muscle-stripped ileal preparations increases short-circuit current (EC(50) = 8.2 nmol L(-1)) in a TTX-insensitive manner. The PROK1-evoked Cl- secretion is reduced by piroxicam (non-selective cyclooxygenase inhibitor), and a prostaglandin EP(4) receptor antagonist (AH23848), but not a thromboxane receptor antagonist (GR32191B).

CONCLUSIONS & INFERENCES

These results demonstrate that PROK1 has oral prokinetic and secretogogue activity and that it acts on the intestinal mucosa via PK-R1 and prostaglandin receptors to mediate these effects.

Reduced-intensity conditioning followed by peripheral blood stem cell transplantation for adult patients with high-risk acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) with high-risk features has a poor prognosis in adults despite aggressive chemotherapy. Reduced-intensity conditioning (RIC) is a lower toxicity alternative for high-risk patients requiring hematopoietic cell transplantation (HCT); however, it has not been widely used for ALL. We conducted a retrospective study of 24 high-risk adult ALL patients who received an RIC regimen of fludarabine (Flu)/melphalan (Mel) prior to allogeneic peripheral blood stem cell transplantation (PBSCT) between 6/14/02 and 6/15/07 at the City of Hope. Indications for the RIC regimen were: (1) aged 50 years or older (42%), (2) compromised organ function (54%), or (3) recipient of a previous HCT (37.5%). Patients had a median age of 47.5 years and the median follow-up was 28.5 months for living patients. Both overall survival (OS) and disease-free survival (DFS) at 2 years was 61.5%. Relapse incidence was 21.1% and nonrelapse mortality (NRM) was 21.5% at 2 years. Chronic graft-versus-host (cGVHD) developed in 86% of evaluable patients. In this series, no significant correlations were made between outcomes and patient age, presence of Philadelphia chromosome, relatedness of donor source, or prior HCT. These high survival rates for high-risk ALL patients following RIC HCT may offer a promising option for patients not eligible for a standard myeloablative transplant.

Phase II trial of a transplantation regimen of yttrium-90 ibritumomab tiuxetan and high-dose chemotherapy in patients with non-Hodgkin's lymphoma

PURPOSE

This phase II trial evaluated the safety and efficacy of combining yttrium-90 (90Y) ibritumomab tiuxetan with high-dose carmustine, cytarabine, etoposide, and melphalan (BEAM) and autologous stem-cell transplantation in patients with non-Hodgkin's lymphoma who were considered ineligible for total-body irradiation because of older age or prior radiotherapy.

PATIENTS AND METHODS

Between May 2002 and January 2006, 14 days before autologous stem-cell transplantation, 41 patients with non-Hodgkin's lymphoma received standard-dose 90Y ibritumomab tiuxetan (14.8 MBq/kg [0.4 mCi/kg]) followed by high-dose BEAM.

RESULTS

The median age was 60 years (range, 19 to 78 years), and the median number of previous therapies was two (range, one to six). Disease histologies were diffuse large B-cell (n = 20), mantle cell (n = 13), follicular (n = 4), and transformed lymphoma (n = 4). With a median follow-up of 18.4 months (range, 5.5 to 53.3 months) the estimated 2-year overall and progression-free survival were 88.9% (95% CI, 75.3% to 95.2%) and 69.8% (95% CI, 56.4% to 79.7%). The median time to WBC engraftment was 11 days (range, 9 to 26 days) and time to platelet engraftment was 12 days (range, 3 to 107 days). Adverse events were similar to those seen historically with high-dose BEAM alone, and included grade 3 or 4 pulmonary toxicity in 10 patients.

CONCLUSION

Adding 90Y ibritumomab tiuxetan to high-dose BEAM with autologous stem-cell transplantation is feasible and has a toxicity and tolerability profile similar to that observed with BEAM alone. Rates of progression-free survival seen in these patients are promising and warrant additional study.

Clinical and pathologic analysis of 16 cases of relapsed chronic myeloid leukemia after stem cell transplantation

Chronic myeloid leukemia (CML) is a myeloproliferative disease that originates in an abnormal pluripotent bone marrow stem cell and is characteristically associated with the Philadelphia chromosome and/or the bcr/abl fusion gene. Despite the exciting success of the bcr/abl tyrosine kinase-specific inhibitor imatinib for CML treatment, hematopoietic stem cell (bone marrow or peripheral blood stem cell) transplantation (HCT) remains the only "curative" approach for the majority of patients. Although HCT outcomes for patients with CML have improved considerably during the past 2 decades, relapse after HCT may occur. We analyzed the clinical and pathologic features of 16 cases of hematologically relapsed CML after HCT during a 5-year period at City of Hope National Medical Center, Duarte, CA. The results of our analysis showed that relapsed CML after HCT frequently manifested with advanced disease with a more aggressive clinical course and was often refractory to therapy. The frequency of acute leukemic transformation at time of relapse was largely associated with pre-HCT disease status and acquired secondary cytogenetic abnormalities. Disease mortality in patients with relapsed CML after HCT was closely associated with advanced disease and HCT-related complications.

Intravenous versus oral busulfan as part of a busulfan/cyclophosphamide preparative regimen for allogeneic hematopoietic stem cell transplantation: decreased incidence of hepatic venoocclusive disease (HVOD), HVOD-related mortality, and overall 100-day mortality

Hepatic venoocclusive disease (HVOD) is a complication of allogeneic hematopoietic stem cell transplantation (HSCT) and is a well-recognized dose-limiting toxicity of oral busulfan (Bu)-based preparative regimens. The unpredictable absorption of oral Bu from the gastrointestinal (GI) tract and hepatic first-pass effects have led to the development of an intravenous Bu preparation (i.v. Bu). The purpose of this retrospective comparison was to evaluate the incidence rate of HVOD and the 100-day mortality rate in patients treated with a busulfan/cyclophosphamide (BuCy2) regimen in which either oral Bu or i.v. Bu was administered. Data from 2 similar groups of patients treated between March 1995 and December 1997 were analyzed. Thirty patients were treated with oral Bu (1 mg/kg x 16 doses) at City of Hope and 61 patients were treated with i.v. Bu (0.8 mg/kg x 16 doses) in a multicenter trial involving 7 sites. Bu was followed by Cy (60 mg/kg x 2 days) and a histocompatible-sibling-donor HSCT. In the i.v. Bu treatment group, 48% of the patients were classified as heavily pretreated (> or = 3 prior chemotherapy regimens, prior radiation, or prior HSCT) with 13% having had a prior HSCT and 75% having active disease at the time of transplantation. According to the same classification criteria, 33% of the patients in the oral-Bu treatment group were considered heavily pretreated, with 23% having had a prior HSCT and 80% having active disease at the time of transplantation. The incidence rates of clinically diagnosed HVOD were 5/61 (8%) and 10/30 (33%) after i.v. and oral Bu, respectively. HVOD-related mortality occurred in 2 (3.3%) of 61 i.v. and 6 (20%) of 30 oral Bu patients. The (standardized) Jones criteria for HVOD were met by 4.9% of i.v. and 20% of oral Bu patients. Univariate logistic regression analysis identified oral versus i.v. Bu (P = .001) and a diagnosis of myelodysplastic syndrome (P = .04) as statistically significant factors in the development of HVOD, with prior extensive treatment identified as marginally significant (P = .25). No other demographic parameter was found to be significant. After adjustment for prior treatment, multivariate analyses showed that the use of oral versus i.v. Bu was the strongest predictor for development of HVOD (odds ratio, 7.5; 95% confidence interval, 2.1-27.2; P = .002). This study showed that the incidence rate of HVOD is significantly lower (P = .002) and the 100-day survival rate significantly higher (P = .002) in patients treated with i.v. Bu than in patients treated with oral Bu when Bu is used as part of a BuCy2 preparative regimen for allogeneic HSCT.

The immunology of primary biliary cirrhosis: the end of the beginning?

The chronic liver disease primary biliary cirrhosis (PBC) is characterised by autoreactive B-cell and T-cell responses directed against mitochondrial antigens. In recent years these responses have been extensively characterised and the principal PBC associated autoantigen identified as pyruvate dehydrogenase complex (PDC). The identification of anti-PDC responses (present in over 95% of PDC patients) has given rise to important questions pertinent to our understanding of the pathogenesis of PBC. What specific role to anti-PDC responses play in target cell damage? How and why does immune tolerance break down to as highly conserved and ubiquitously expressed self-antigen as PDC? Why does breakdown in tolerance to an antigen present in all nucleated cells result in damage restricted to the intra-hepatic bile ducts? In attempting to answer these key questions we have, in this review, proposed a unifying hypothesis for the pathogenesis of PBC.

Mutation analysis of the CDKN2A promoter in Australian melanoma families

Approximately 50% of all melanoma families worldwide show linkage to 9p21-22, but only about half of these have been shown to contain germ line CDKN2A mutations. It has been hypothesized that a proportion of these families carry mutations in the noncoding regions of CDKN2A. Several Canadian families have been reported to carry a mutation in the 5' UTR, at position -34 relative to the start site, which gives rise to a novel AUG translation initiation codon that markedly decreases translation from the wild-type AUG (Liu et al., 1999). Haplotype sharing in these Canadian families suggested that this mutation is of British origin. We sequenced 1,327 base pairs (bp) of CDKN2A, making up 1,116 bp of the 5' UTR and promoter, all of exon 1, and 61 bp of intron 1, in at least one melanoma case from 110 Australian families with three or more affected members known not to carry mutations within the p16 coding region. In addition, 431 bp upstream of the start codon was sequenced in an additional 253 affected probands from two-case melanoma families for which the CDKN2A mutation status was unknown. Several known polymorphisms at positions -33, -191, -493, and -735 were detected, in addition to four novel variants at positions 120, -252, -347, and -981 relative to the start codon. One of the probands from a two-case family was found to have the previously reported Q50R mutation. No family member was found to carry the mutation at position -34 or any other disease-associated mutation. For further investigation of noncoding CDKN2A mutations that may affect transcription, allele-specific expression analysis was carried out in 31 of the families with at least three affected members who showed either complete or "indeterminate" 9p haplotype sharing without CDKN2A exonic mutations. Reverse transcription polymerase chain reaction and automated sequencing showed expression of both CDKN2A alleles in all family members tested. The lack of CDKN2A promoter mutations and the absence of transcriptional silencing in the germ line of this cohort of families suggest that mutations in the promoter and 5' UTR play a very limited role in melanoma predisposition.

Integrative neuroimmunomodulation of gastrointestinal function during enteric parasitism

Enteric helminths have a significant impact on the structure, function, and neural control of the gastrointestinal (GI) tract of the host. Interactions between the host's nervous and immune systems redirect activity in neuronal circuits intrinsic to the gut into an alternative repertoire of defensive and adaptive motor programs. Gut inflammation and activation of the enteric neuroimmune axis play integral roles in the dynamic interaction between host and parasite that occurs at the mucosal surface. Three inter-related themes are stressed in this review to underscore the pivotal role that neural control mechanisms play in the host's GI tract functional responses to enteric parasitism. First, we address the discovery that signaling molecules of both parasite and host origin can reorient the dynamic ecology of enteric host-parasite interactions. Second, we explore what has been learned from investigations of altered gut propulsive and secretomotor reflex activities that occur during enteric parasitic infections and the emerging picture derived from these studies that elucidates how nerves help facilitate and orchestrate functional reorganization of the parasitized gut. Third, we provide an overview of the direct impact that enteric parasitism has on nerve cell function and neurotransmission pathways in both the enteric and central nervous systems of the host. In summary, this review highlights and clarifies the complex mechanisms underlying integrative neuroimmunophysiological responses to the presence of both invasive and noninvasive enteric helminths and identifies directions for future research investigations in this highly important but understudied area.

Longitudinal study of daily intake and excretion of lead in newly born infants

As an adjunct to a study of lead mobilization during pregnancy and lactation, we have obtained estimates of the daily lead intake and excretion/intake for 15 newly born infants monitored for at least 6 months postpartum. The longitudinal data presented reflect the far lower levels of environmental contribution to lead in blood in the 1990's than that in the earlier studies from the 1970's and early 1980's, the last period for which such dietary information is available in newly born infants. Infants were breast-fed or formula-fed or both and, in the second quarter, were usually fed solid foods (beikost). Lead concentrations were as follows: lead in breast milk, ranged from 0.09 to 3.1 microg/kg with a geometric mean of 0.55 microg/kg, lead in infant formula ranged from 0.07 to 11.4 microg/kg with a geometric mean of 1.6 microg/kg, and lead in beikost ranged from 1.1 to 27 microg/kg with a geometric mean of 2.9 microg/kg. Daily lead intakes ranged from 0.04 to 0.83 microg/kg body weight/day with a geometric mean of 0.23 microg Pb/kg body weight/day, and excretion/intake ranged from 0.7 to 22 with a geometric mean of 2.6. There was no significant difference at the 5% level in lead concentration in daily intakes and excretion/intake for the first quarter versus the second quarter for this small number of subjects. Assuming that there was no contribution from environmental samples such as house dust and ambient air, the contribution of diet to blood has been estimated from lead isotopic measurements with the following ranges: for breast milk only as the dietary source, 40 to 65%; for breast milk and infant formula as the dietary sources, 15 to 70%; and for infant formula and beikost, 20 to 80%. The geometric mean value of the dietary contribution to blood over the 6-month period of approximately 35% is consistent with earlier estimates of uptake of lead in blood in newly born infants when environmental lead concentrations were much higher. Other sources such as air, soil, and dust are considered to contribute minimally to blood lead in these infants because of the low 206Pb/204Pb ratios in environmental media. Thus, we consider that the increased excretion over intake, along with other evidence, reflects mobilization of infant tissues arising especially from rapid bone turnover at this stage of life; the tissue lead has been identified isotopically in urine.

Contribution of lead from calcium supplements to blood lead

We conducted a case-control study to determine the contribution of lead to blood from consumption of calcium supplements approximating the recommended daily intakes over a 6-month period. Subjects were males and females ages 21 to 47 years (geometric mean 32 years) with a geometric mean blood lead concentration of 2.5 microg/dL. They were subdivided into three groups. One treatment group (n = 8) was administered a complex calcium supplement (carbonate/phosphate/citrate) and the other treatment group (n = 7) calcium carbonate. The control group (n = 6) received no supplement. The lead isotopic compositions of the supplements were completely different from those of the blood of the subjects, allowing us easily to estimate contribution from the supplements. The daily lead dose from the supplements at 100% compliance was about 3 microg Pb. Three blood samples were taken at 2-month intervals before treatment to provide background values, and three were taken during treatment. Subjects in the treatment group were thus their own controls. Lead isotopic compositions for the complex supplement showed minimal change during treatment compared with pretreatment. Lead isotopic compositions in blood for the calcium carbonate supplement showed increases of up to 0.5% in the (206)Pb/(204)Pb ratio, and for all isotope ratios there was a statistically significant difference between baseline and treatment (p < 0.005). The change from baseline to treatment for the calcium carbonate supplement differed from that for both the control group and the group administered the complex supplement. Blood lead concentrations, however, showed minimal changes. Variations in blood lead levels over time did not differ significantly between groups. Our results are consistent with earlier investigations using radioactive and stable lead tracers, which showed minimal gastrointestinal absorption of lead in the presence of calcium (+/- phosphorus) in adults. Even though there is no discernible increase in blood lead concentration during treatment, there are significant changes in the isotopic composition of lead in blood arising from the calcium carbonate supplement, indicating a limited input of lead from diet into the blood. Because calcium carbonate is overwhelmingly the most popular calcium supplement, the changes we have observed merit further investigation. In addition, this type of study, combined with a duplicate diet, needs to be repeated for children, whose fractional absorption of lead is considerably higher than that of adults.

Effects of allogeneic bone marrow transplantation on recipient bone mineral density: A prospective study

Allogeneic bone marrow transplant (BMT) recipients have many known risk factors for developing decreased bone mineral density (BMD) after transplantation. We performed a prospective sequential evaluation of BMD in the lumbar spine and nondominant hip using dual-energy x-ray absorptiometry (DEXA) in a cohort of 47 adult patients (median age, 43 years) who were undergoing radiation-based BMT for hematologic malignancies. Baseline DEXA studies were performed before BMT and repeated at 3 to 4 months, 6 to 8 months, and 12 to 14 months after BMT. The majority of patients (60%) had been minimally treated with combination cytotoxic chemotherapy, having received no more than 1 treatment regimen before BMT. Graft-versus-host disease prophylaxis consisted of cyclosporine in combination with either methotrexate or prednisone, or both. Mean lumbar spine and hip BMD were normal before BMT (spine: 1.01 g/cm2, z score = 96%; hip: 0.86 g/cm2, z score = 100%) and gradually decreased (spine: 0.98 g/cm2, z score = 94%; hip: 0.76 g/cm2, z score = 91%) at 12 to 14 months. These declines were statistically significant (P < .006 and < .002 for lumbar spine; P < .001 and < .001 for hip). In addition, the sharpest decline occurred during the first 6 months after BMT and was more marked in the hip than the lumbar spine. These data suggest that BMT adversely affects BMD in this patient population.

Secretory autoantibodies in primary biliary cirrhosis (PBC)

It is unclear how breakdown in immune tolerance to the ubiquitous self-antigen pyruvate dehydrogenase complex (PDC), seen in the autoimmune liver disease PBC, gives rise to tissue damage with such a limited distribution (restricted to the liver and salivary and lachrymal glands). One property shared by these tissues is the ability to export secretory IgA by the process of transcytosis. The aim of this study was to address whether active transcytosis of anti-PDC IgA occurs across epithelial surfaces in PBC, a finding that might implicate mucosal specific immune mechanisms in the pathogenesis of this disease. Parotid saliva was collected from PBC patients (n = 44), normal controls (n = 28) and PBC patients post-liver transplantation (n = 11). IgA and secretory component-positive antibodies specific for human PDC were quantified by ELISA and immunoblotting. PBC patients (but not control subjects) had anti-PDC IgA in their saliva. The strong correlation seen between titres detected using anti-IgA and anti-secretory component antibodies suggests that this is predominantly secretory IgA reaching the saliva by the active process of epithelial transcytosis. Titres of anti-PDC IgA remain high in PBC patients saliva post-liver transplant. Findings from studies of IgA in viral infection models raise the possibility that anti-PDC IgA could, whilst undergoing transcytosis, bind to newly translated PDC components in the cytoplasm of the epithelial cells transporting them out of the cell and inducing metabolic damage. This model would, if correct, help to explain the mechanism and tropism of tissue damage in PBC and the aberrant pattern of expression of PDC on the apical surface of biliary and salivary epithelial cells reported in this disease.

Urinary excretion of lead during pregnancy and postpartum

We have compared lead isotopic ratios and lead concentrations in 53 spot urine and 59 24-h urine samples from 13 subjects covering the interval from pre-pregnancy through 180 days postpartum to estimate the amount of lead excreted in urine and renal clearance relative to blood. The total amount of lead excreted in 24-h urine samples ranges from 0.8 to 5.9 microg Pb with an arithmetic mean of 2.2+/-1.1 microg (geometric mean 1.90 microg). This compares with amounts of 0.9-10 microg of extra lead per day estimated to be released into blood from the skeleton during pregnancy and postpartum. There were no differences in excretion rates during the trimesters of pregnancy and between pregnancy and postpartum time periods. The renal clearance relative to blood ranged from 0.8 to 10 g/h (arithmetic mean 3.2+/-1.9; geometric mean 2.7). Renal clearance relative to blood was somewhat higher in trimesters 2 and 3 compared with postpartum 150-180 days (P = 0.004, 0.006, respectively). Reassessment of earlier published blood and dietary data for Australian pregnant controls indicates there is no increased gastrointestinal absorption of lead during pregnancy and postpartum. This differs from calcium, which shows increased absorption during late pregnancy. In light of the inconvenience of sampling and potential contamination at the low levels of lead found in most of these subjects, we do not consider the 24 h urines to provide sufficient useful information.

Experimental autoimmune cholangitis: a mouse model of immune-mediated cholangiopathy

BACKGROUND

Primary biliary cirrhosis (PBC) is characterised by intra-hepatic immune-mediated cholangiopathy (non-suppurative destructive cholangitis (NSDC)). Although auto-reactive immune responses against pyruvate dehydrogenase complex (PDC) have been characterised in PBC, the lack of an animal model of the disease has limited study of the mechanisms of disease induction and the development of novel approaches to therapy.

AIMS

To develop and validate a mouse model of immune-mediated cholangiopathy relevant for future use in the study of the aetio-pathogenesis and therapy of PBC.

METHODS

Female SJL/J, C57BL/6, NOD and BALB/c mice were sensitised with PDC, its purified E2/E3BP component, and a PDC-E2 derived peptide p163 (a dominant T-cell epitope in humans) in complete Freund's adjuvant (CFA). Morphological changes were assessed under light microscopy by a hepatic histopathologist blinded to the experimental details. Antibody responses to PDC were studied by ELISA and PDC inhibition assay.

RESULTS

An initial series of experiments was performed to survey the susceptibility of female mice of a range of strains to the induction of NSDC by i.p. sensitisation with PDC, PDC-E2/E3BP or p163 in CFA. Although each animal showed a specific antibody response following sensitisation, it was found that NSDC development (assessed at 30 weeks post-sensitisation) was restricted to SJL/J mice following sensitisation with any of the mitochondrial antigen preparations. A subsequent series of experiments was performed to examine the specificity and aetiology of this disease. Significant bile duct lesions were only seen in SJL/J animals following sensitisation with CFA containing PDC, and were absent from CFA only and un-sensitised controls. Kinetic analysis revealed that this pathology developed slowly, but a high incidence of animals with severe lesions was observed after 30 weeks.

CONCLUSIONS

We have described a model of experimental autoimmune cholangitis (EAC) with immunological (anti-PDC antibodies) and histological (immune-mediated cholangiopathy) features suggestive of PBC. This model may be useful in further defining the role of self-tolerance breakdown in the development of this condition.

Urinary lead isotopes during pregnancy and postpartum indicate no preferential partitioning of endogenous lead into plasma

We have compared lead isotopic ratios and lead concentrations in 51 matched blood and spot urine samples from 13 subjects covering the interval from before pregnancy through 180 days postpartum to evaluate whether mobilization of lead from the maternal skeleton is preferentially partitioned into plasma; we have used urine as an isotopic proxy for plasma. There was no statistically significant difference in the lead 206/lead 204 and lead 207/lead 206 ratios over pregnancy. The urine data for the postpartum period are in the opposite relationships to that predicted for a preferential partitioning hypothesis. These data provide no support for the hypothesis that lead released from the skeleton is preferentially partitioned into plasma.

Respiratory pathways and oxygen toxicity in Phanerochaete chrysosporium

Phanerochaete chrysosporium maintained on glucose as the carbon source contained severely impaired mitochondria that were characterised by the loss of both succinate dehydrogenase and cytochrome oxidase activities. These cells maintained a constant value for energy charge using anaerobic metabolism. Cells with these properties express lignin peroxidase when supplied with a pure oxygen atmosphere, which may reflect a response to accumulating reactive oxygen species. Cells maintained on cellulose retained fully functional mitochondria, but expressed lignin peroxidase without being exposed to a pure oxygen atmosphere. In the cells maintained on cellulose, mitochondrial function may be limited by the supply of glucose, leading to the accumulation of reactive oxygen species.

Suppression of food intake is linked to enteric inflammation in nematode-infected rats

Our aim was to investigate the cause-effect relationship between intestinal inflammation induced by infection with enteric stages of Trichinella spiralis and decreased host food intake. A suppression of food intake in T. spiralis-infected rats occurred within the first 24 h postinfection (PI) and was maximized by day 6 PI. Food intake, cumulated over an 8-day PI period, decreased by 59% compared with uninfected animals. The anti-inflammatory glucocorticoid betamethasone 21-phosphate was orally administered to rats in their drinking water to suppress T. spiralis-induced jejunal inflammation. When treated with a low dose of glucocorticoid (5.2 microg/ml), food intake in infected rats was still significantly reduced, but only by 21% compared with glucocorticoid-treated, uninfected rats. At the highest glucocorticoid dose (10.4 microg/ml) administered, infection-induced reduction in food intake was not different from that of glucocorticoid-treated, uninfected counterparts. The elevation in jejunal myeloperoxidase activity caused by infection was also significantly blunted by oral glucocorticoid treatment. Our results suggest that suppressed host food intake during enteric T. spiralis infection is directly linked to intestinal inflammation.

Breakdown of tolerance to pyruvate dehydrogenase complex in experimental autoimmune cholangitis: a mouse model of primary biliary cirrhosis

The autoimmune liver disease primary biliary cirrhosis (PBC) is characterized by autoreactive responses to a highly conserved self-antigen, pyruvate dehydrogenase complex (PDC). We recently reported the development of PBC-like lesions in SJL mice sensitized with PDC and have named this model disease experimental autoimmune cholangitis (EAC). In the present study, the breakdown of tolerance to PDC has been investigated in animals sensitized for EAC. Splenic mononuclear cells from SJL mice sensitized with bovine heart PDC (bPDC) in adjuvant showed T-cell proliferative and mixed Th1/Th2 cytokine secretory responses following in vitro stimulation with bPDC. Despite the likelihood of extensive sequence homology with mouse PDC (there is a greater than 95% sequence identity between rat and human PDC-E2 subunits), bPDC was highly immunogenic inducing significant T- and B-cell responses in the absence of any form of adjuvant. The multi-subunit quaternary structure of intact PDC was critical for this immunostimulatory activity because no response was produced by sensitization with monomeric recombinant PDC-E2 inner lipoyl domain. Mice sensitized with bPDC and CFA developed, within 2 weeks of sensitization, high-titer antibody responses reactive with bPDC that were fully cross-reactive with the murine homologue. Breakdown of T-cell tolerance to self-PDC took significantly longer, not being seen until 20 weeks postsensitization; a similar length of time to that previously shown to be required for EAC lesion development. Conclusions drawn from these data may have important implications for our understanding, and therapeutic manipulation, of PBC in humans.

Nematode-induced jejunal inflammation in the ferret causes long-term changes in excitatory neuromuscular responses

Enteric infections in animals and humans have proven the link between mucosal inflammation and gastrointestinal motor dysfunction. The goal of the present investigation was to study the long-term effects of mucosal inflammation on the neuromuscular functions of the small intestine in a ferret model of primary Trichinella spiralis infection. Myeloperoxidase activity and isometric contractions of isolated jejunal muscles were studied on days 8, 30, and 60 postinfection (PI). The peak increase in myeloperoxidase activity seen on day 8 PI returned to normal levels by day 60 PI. Contractions of the longitudinal and circular muscles evoked by electrical field stimulation of enteric nerves on day 8 PI showed no difference when compared with uninfected controls. However, during this enteric phase of the infection, neurally mediated responses were characterized by a disturbance in the balance between cholinergic and nonadrenergic, noncholinergic (NANC) excitation with both a reduction of cholinergic and a reciprocal enhancement of NANC neurotransmission. On days 30 and 60 PI the amplitude of neurally mediated responses and the balance between cholinergic and NANC excitation were restored in the circular but not in the longitudinal muscle. In addition, there were changes in the effector function involving smooth muscle hyperresponsiveness to high K+ or carbachol on days 8, 30, and 60 PI. However, a significant reduction in EC50 for carbachol was found only on day 60 PI. The results demonstrate that T. spiralis infection results in alterations of muscle contractility and enteric neurotransmission that persist after the resolution of mucosal inflammation.

Characterization of the autoantibody responses to recombinant E3 binding protein (protein X) of pyruvate dehydrogenase in primary biliary cirrhosis

Autoantibodies to the pyruvate dehydrogenase complex (PDC) are present in the serum of more than 95% of patients with primary biliary cirrhosis (PBC), the major epitope being the inner lipoyl domain of the E2 component. Immunoblotting suggests a similar prevalence of antibodies to a tightly associated lipoic acid-containing protein, E3 binding protein (E3BP). Attempts to resolve E3BP from E2 have been unsuccessful, restricting study of the nature and significance of antibody responses to the individual proteins. In particular, it is unclear (1) whether there is true cross-reactivity between E3BP and E2 and, if so, which is the originating response and (2) whether autoantibodies preferentially bind a lipoylated epitope on E3BP as is the case with PDC-E2. In this study, complementary DNAs encoding rE2, full-length rE3BP, its single lipoyl domain (rLip), and core domain (rE3BPCore) were cloned, and the proteins were expressed in Escherichia coli. Sera from 47 PBC patients were studied by immunoblotting and enzyme-linked immunosorbent assay (ELISA) against rE2, rE3BP, rE3BPCore, and both unlipoylated (U) and lipoylated (L) rLip. All sera were reactive by ELISA to some degree with all recombinant proteins except rE3BPCore, to which only 6 of 47 showed any reactivity. Significant correlations (P <.0001) were observed when comparing absorbance values for rE3BP with both rLip (U) (r = 0.793) and (L) (r = 0.963). The mean absorbance for rLip (U, 0.26 +/- 0.05) was, however, significantly lower than the absorbance for rLip (L) (0.78 +/- 0.12; P <.0001). After probing by immunoblotting and elution of antibodies from rE2 and rE3BP, subsequent reprobing against the components in whole PDC revealed true cross-reactivity. In summary, the response to E3BP is primarily directed against the lipoylated domain of the protein. It still remains unclear, however, whether the initial breakdown of tolerance is to E2 or E3BP.

Ethnicity and attitudes towards life sustaining technology

The ethical and legal implications of decisions to withhold and withdraw life support have been widely debated. Making end-of-life decisions is never easy, and when the cultural background of doctor and patient differ, communication about these issues may become even more difficult. In this study, we examined the attitudes of people aged 65 and older from different ethnic groups toward foregoing life support. To this end, we conducted a survey of 200 respondents from each of four ethnic groups: European-American, African-American, Korean-American and Mexican-American (800 total), followed by in-depth ethnographic interviews with 80 respondents. European-Americans were the least likely to both accept and want life-support (p < 0.001). Mexican-Americans were generally more positive about the use of life-support and were more likely to personally want such treatments (p < 0.001). Ethnographic interviews revealed that this was due to their belief that life-support would not be suggested if a case was truly hopeless. Compared to European-Americans, Korean-Americans were very positive regarding life-support (RR = 6.7, p < 0.0001); however, they did not want such technology personally (RR = 1.2, p = 0.45). Ethnographic interviews revealed that the decision of life support would be made by their family. Compared to European-Americans, African-Americans felt that it was generally acceptable to withhold or withdraw life-support (RR = 1.6, p = 0.06), but were the most likely to want to be kept alive on life-support (RR = 2.1, p = 0.002). Ethnographic interviews documented a deep distrust towards the health care system and a fear that health care was based on one's ability to pay. We concluded that (a) ethnicity is strongly related to attitudes toward and personal wishes for the use of life support in the event of coma or terminal illness, and (b) this relationship was complex and in some cases, contradictory.

Psychometric properties of a Chinese translation of the SF-36 health survey questionnaire in the Well Elderly Study

OBJECTIVES

To evaluate the psychometric properties of a Chinese translation of the 36-item Short Form Health Survey (SF-36) in the Well Elderly Study--a randomized clinical trial designed to evaluate the effectiveness of preventive occupational therapy services specifically tailored for multiethnic, independent-living, older adults.

METHODS

Translation and back-translation procedures were used to obtain appropriate meanings for the SF-36 survey questions and to ensure face, functional, and conceptual equivalence.

RESULTS

Statistical analyses demonstrated satisfactory reliability and validity, with the results generally similar to those reported for older Anglo adults.

DISCUSSION

As the percentage of older adults of diverse ethnicity increases, the need for health care research and service strategies that can effectively include multiple ethnicities becomes paramount. The results of this study suggest that a Chinese-translated SF-36 can be used to assess multiple dimensions of health in a Mandarin-speaking population of older adults.