Astegolimab (anti-ST2) efficacy and safety in adults with severe asthma: A randomized clinical trial

BACKGROUND

The IL-33/ST2 pathway is linked with asthma susceptibility. Inhaled allergens, pollutants, and respiratory viruses, which trigger asthma exacerbations, induce release of IL-33, an epithelial-derived "alarmin." Astegolimab, a human IgG₂ mAb, selectively inhibits the IL-33 receptor, ST2. Approved biologic therapies for severe asthma mainly benefit patients with elevated blood eosinophils (type 2-high), but limited options are available for patients with low blood eosinophils (type 2-low). Inhibiting IL-33 signaling may target pathogenic pathways in a wider spectrum of asthmatics.

OBJECTIVES

This study evaluated astegolimab efficacy and safety in patients with severe asthma.

METHODS

This double-blind, placebo-controlled, dose-ranging study (ZENYATTA [A Study to Assess the Efficacy and Safety of MSTT1041A in Participants With Uncontrolled Severe Asthma]) randomized 502 adults with severe asthma to subcutaneous placebo or 70-mg, 210-mg, or 490-mg doses of astegolimab every 4 weeks. The primary endpoint was the annualized asthma exacerbation rate (AER) at week 54. Enrollment caps ensured ∼30 patients who were eosinophil-high (≥300 cells/μL) and ∼95 patients who were eosinophil-low (<300 cells/μL) per arm.

RESULTS

Overall, adjusted AER reductions relative to placebo were 43% (P = .005), 22% (P = .18), and 37% (P = .01) for 490-mg, 210-mg, and 70-mg doses of astegolimab, respectively. Adjusted AER reductions for patients who were eosinophil-low were comparable to reductions in the overall population: 54% (P = .002), 14% (P = .48), and 35% (P = .05) for 490-mg, 210-mg, and 70-mg doses of astegolimab. Adverse events were similar in astegolimab- and placebo-treated groups.

CONCLUSIONS

Astegolimab reduced AER in a broad population of patients, including those who were eosinophil-low, with inadequately controlled, severe asthma. Astegolimab was safe and well tolerated.

Abstract OT2-04-03: Examining personalized radiation therapy (EXPERT): A randomised phase III trial of adjuvant radiotherapy vs observation in patients with molecularly characterized luminal A breast cancer

Background

Radiation therapy (RT) after breast conserving surgery (BCS) is the current standard of care for patients with early stage breast cancer. However, individual absolute recurrence risks and hence benefits of RT vary substantially. A study showed significant association between local recurrence (LR) risk and PAM50-defined intrinsic subtypes and Risk of Recurrence scores (ROR).1

The objective of EXPERT, a co-lead study of Breast Cancer Trials-Australia & New Zealand (BCT-ANZ), and Breast International Group (BIG), is to optimize local therapy for early breast cancer through precise individualized quantification of LR risk to identify patients for whom RT after BCS may be safely omitted.

Trial design

This is a randomized, non-inferiority, phase III study of women who plan to receive adjuvant endocrine therapy for Prosigna (PAM50)-defined luminal A breast cancer with ROR ≤60 resected by BCS.

Women are randomized to receive adjuvant whole breast RT and endocrine therapy or endocrine therapy alone and followed-up for 10 years after randomization.

Major eligibility criteria

Females aged ≥50 years; histologically confirmed invasive breast carcinoma ≤2 cm, grade 1 or 2, ER and PgR ≥10%, HER2-negative and node-negative; treated by BCS with negative margins for invasive carcinoma and associated DCIS; Prosigna (PAM50)-defined Luminal A subtype and ROR ≤60; and plan to receive adjuvant endocrine therapy.

Specific aims

Primary: To determine if omission of RT is not inferior to RT in terms of LR-free interval after BCS.

Secondary: To evaluate the impact of omission of RT on regional, local-regional and distant recurrence-free interval; disease-free survival (DFS); invasive DFS; overall survival; salvage RT or mastectomy rate; toxicity; endocrine therapy adherence; patient reported outcomes; and health economic outcomes.

Statistical methods

An estimated 5-year LR rate in the target population is expected to be 1% with RT. A rate of 4% is considered non-inferior as a worthwhile trade-off against RT toxicity. Using O'Brien-Fleming boundary for rejecting non-inferiority, 29 LR events are required for final analysis expected 8 years after the first patient is randomized. Two interim analyses will be conducted after 10 and 21 events. If the stratified log-rank test statistic exceeds the upper boundary at interim or final analysis, the hypothesis of non-inferiority will be rejected and it will be concluded that no RT is inferior to RT.

Accrual: Target (1170), actual: 82 (June 2018)

The study was activated in Australia in August 2017, with global activation planned for Q4 2018. Recruitment is expected to be completed in 4.5 years.

Contact information

Professor Boon Chua, UNSW Sydney and Prince of Wales Hospital, NSW, Australia; email boon.chua@health.nsw.gov.au; T +61 2 49255239. Registration: NCT02889874

References

Fitzal F, Filipits M, Fesl C, et al. Predicting local recurrence using PAM50 in postmenopausal endocrine responsive breast cancer patients. JCO 2014;32(15 suppl):1008.

Citation Format: Chua BH, Gray K, Krishnasamy M, Regan M, Zdenkowski N, Loi S, Mann B, Forbes JF, Wilcken N, Spillane A, Martin A, Badger H, Jafari S, Fong A, Mavin C, Corachan S, Arahmani A, Martinez J-L, Francis P. Examining personalized radiation therapy (EXPERT): A randomised phase III trial of adjuvant radiotherapy vs observation in patients with molecularly characterized luminal A breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-03.

A phase I, randomized, observer-blinded, single and multiple ascending-dose study to investigate the safety, pharmacokinetics, and immunogenicity of BITS7201A, a bispecific antibody targeting IL-13 and IL-17, in healthy volunteers

BACKGROUND

Inhibition of interleukin (IL)-13, a Type 2 inflammatory mediator in asthma, improves lung function and reduces exacerbations; however, more effective therapies are needed. A subset of asthma patients also exhibits elevated IL-17, which is associated with greater disease severity, neutrophilic inflammation, and steroid resistance. BITS7201A is a novel, humanized bispecific antibody that binds and neutralizes both IL-13 and IL-17.

METHODS

Safety, pharmacokinetics, and immunogenicity of BITS7201A were evaluated in a phase 1 study. Part A was a single ascending-dose design with 5 cohorts: 30-, 90-, and 300-mg subcutaneous (SC), and 300- and 750-mg intravenous (IV). Part B was a multiple ascending-dose design with 3 cohorts: 150-, 300-, and 600-mg SC every 4 weeks × 3 doses. Both parts enrolled approximately 8 healthy volunteers into each cohort (6 active: 2 placebo). Part B included an additional cohort of patients with mild asthma (600-mg SC).

RESULTS

Forty-one subjects (31 active, 10 placebo) and 26 subjects (20 active, 6 placebo) were enrolled into Parts A and B, respectively. The cohort with mild asthma patients was terminated after enrollment of a single patient. No deaths, serious adverse events, or dose-limiting adverse events occurred. In Part A, 12 active (39%) and 5 placebo subjects (50%), and in Part B, 6 active (30%) and 3 placebo subjects (50%) experienced at least 1 treatment-emergent adverse event (TEAE). The most common AEs were fatigue (n = 3) and influenza-like illness (n = 2). One injection-site reaction was reported. Two subjects with elevated blood eosinophil counts at baseline had transient elevations in blood eosinophils (≥Grade 2, > 1500 cells/μL). In Parts A and B, 16 of 30 (53%) and 16 of 17 (94%) active subjects, respectively, tested positive for anti-drug antibodies (ADAs). No anaphylaxis or hypersensitivity events occurred. BITS7201A exhibited single- and multiple-dose pharmacokinetic characteristics consistent with an IgG monoclonal antibody; exposure generally increased dose-proportionally. Postdose elevations of the serum pharmacodynamic biomarkers, IL-17AA and IL-17FF, occurred, confirming target engagement.

CONCLUSIONS

BITS7201A was well tolerated, but was associated with a high incidence of ADA formation.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT02748642; registered April 6, 2016 (retrospectively registered).

An Evaluation of Patient Safety Event Report Categories Using Unsupervised Topic Modeling

OBJECTIVE

Patient safety event data repositories have the potential to dramatically improve safety if analyzed and leveraged appropriately. These safety event reports often consist of both structured data, such as general event type categories, and unstructured data, such as free text descriptions of the event. Analyzing these data, particularly the rich free text narratives, can be challenging, especially with tens of thousands of reports. To overcome the resource intensive manual review process of the free text descriptions, we demonstrate the effectiveness of using an unsupervised natural language processing approach.

METHODS

An unsupervised natural language processing technique, called topic modeling, was applied to a large repository of patient safety event data to identify topics, or themes, from the free text descriptions of the data. Entropy measures were used to evaluate and compare these topics to the general event type categories that were originally assigned by the event reporter.

RESULTS

Measures of entropy demonstrated that some topics generated from the unsupervised modeling approach aligned with the clinical general event type categories that were originally selected by the individual entering the report. Importantly, several new latent topics emerged that were not originally identified. The new topics provide additional insights into the patient safety event data that would not otherwise easily be detected.

CONCLUSION

The topic modeling approach provides a method to identify topics or themes that may not be immediately apparent and has the potential to allow for automatic reclassification of events that are ambiguously classified by the event re- porter.

CT scanning reduces the risk of missing a fracture of the thoracolumbar spine

The aim of this study was first, to determine whether CT scans undertaken to identify serious injury to the viscera were of use in detecting clinically unrecognised fractures of the thoracolumbar vertebrae, and second, to identify patients at risk of ‘missed injury’.

We retrospectively analysed CT scans of the chest and abdomen performed for blunt injury to the torso in 303 patients. These proved to be positive for thoracic and intra-abdominal injuries in only 2% and 1.3% of cases, respectively. However, 51 (16.8%) showed a fracture of the thoracolumbar vertebrae and these constituted our subset for study. There were eight women and 43 men with mean age of 45.2 years (15 to 94). There were 29 (57%) stable and 22 (43%) unstable fractures. Only 17 fractures (33.3%) had been anticipated after clinical examination. Of the 22 unstable fractures, 11 (50%) were anticipated. Thus, within the whole group of 303 patients, an unstable spinal injury was missed in 11 patients (3.6%); no harm resulted as they were all protected until the spine had been cleared. A subset analysis revealed that patients with a high Injury Severity Score, a low Glasgow Coma Scale and haemodynamic instability were most likely to have a significant fracture in the absence of positive clinical findings. This is the group at greatest risk.

Clinical examination alone cannot detect significant fractures of the thoracolumbar spine. It should be combined with CT imaging to reduce the risk of missed injury.

Attitudes and practices of healthcare providers regarding gestational diabetes: results of a survey conducted at the 2010 meeting of the International Association of Diabetes in Pregnancy Study Group (IADPSG)

OBJECTIVE

To investigate the attitudes and practices of healthcare providers regarding gestational diabetes mellitus and to identify differences between provider types and geographical locations.

RESEARCH DESIGN AND METHODS

A survey was distributed to participants at the 2010 GDM Pasadena II: International Conference regarding management of gestational diabetes.

RESULTS

Of 250 distributed surveys, there was a 60.8% (n = 152) response rate. Most responders believed it was cost beneficial to treat and screen for gestational diabetes. Approximately 2/3 accepted that the diagnosis of Type 2 diabetes could be made in pregnancy. For the diagnosis of gestational diabetes, c. 60% opted for a one-step screen while 30% opted for a two-step screen. Most responders were comfortable treating a non-pregnant woman with Type 2 diabetes. Ninety per cent of responders initiated antenatal testing at 32-34 weeks for medication-treated gestational diabetes, with a wider variation for diet-treated gestational diabetes. Obstetricians were less comfortable than other providers in treating a non-pregnant woman with Type 2 diabetes, but were more likely to prescribe glyburide. Providers in the USA, compared with those from other countries, were more likely to perform a Caesarean section based on fetal weight, use glibenclamide (glyburide), initiate exercise post-delivery and less likely to check 2-h postprandial glucose levels. At least 80% of responders routinely screened for Type 2 diabetes at 6-12 weeks post-delivery.

CONCLUSION

There are differences internationally and by provider types in attitudes and management regarding gestational diabetes. These findings may be useful in developing strategies for implementing the recent guidelines by the International Association of the Diabetes and Pregnancy Study Groups.

Abstract P3-11-11: A Comparison of Breast Cancer Treatment Rates in British Columbia, Scotland, and Western Australia, and a Comparison with Models of “Optimal” Therapy

Background: Evidence-based optimal utilization models provide estimates of optimal radiotherapy, chemotherapy and hormonal therapy utilization by stage and other clinically relevant patient sub-groups. We therefore compared predicted utilization with actual utilization of radiotherapy, hormone therapy and chemotherapy in 3 jurisdictions with population-based stage and treatment data: British Columbia, Canada; Dundee, Scotland; and Perth, Western Australia.

Methods: Previously published optimal radiotherapy, chemotherapy, and endocrine therapy treatment utilization trees for an Australian population were modified to incorporate epidemiological data from British Columbia, Dundee, and Perth, such that the optimal trees for each region reflected the casemix for each region. Frequency data on patient, tumour, and surgical factors were used to calculate optimal treatment rates for each region. Optimal rates were then compared with actual rates of surgery, radiotherapy, chemotherapy, and endocrine therapy use obtained from 2 population-based and 1 institution-based cancer registries for patients diagnosed with breast cancer between 2000 to 2004. Information on region-specific treatment guidelines was also collected.

Results: Region-specific optimal treatment utilization rates at diagnosis varied between 80% and 81% for radiotherapy (62 to 64% when patient preference is taken into account), 53% to 56% for chemotherapy, and 49% to 54% for endocrine therapy. The predicted ranges were due to local variations in demographics, and tumour stage. Actual radiotherapy utilization was 57%, 49%, and 52%; chemotherapy utilization was 32%, 24%, and 29%; and endocrine therapy utilization was 56%, 64%, and 52% for British Columbia, Dundee, and Perth, respectively. Conclusion: There are significant differences in actual treatment utilisation rates between the study populations. It is unlikely that all of this variation is due to differences in tumour characteristics alone. Actual utilization rates were lower than the calculated optimal rates for radiotherapy and chemotherapy, and higher for endocrine therapy. Differences between actual regional rates of treatment utilization were seen, and were associated with differences in mastectomy rates, and guideline recommendations for treatment use in that region. This methodology allows comparison of the treatment that occurs in a jurisdiction against what would be considered optimal based on evidence.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-11-11.

Demographic, institutional and obstetrical risk factors for postpartum haemorrhage mortality

This study, initially presented at the SMFM Annual Conference in San Diego on 29 January 2009, sought to explore the risk factors for mortality from postpartum haemorrhage (PPH). A total of 138,316 cases of PPH from 1991 to 2000 were identified using the California Health Discharge Database. Data analysed included demographic information and clinical risk factors. PPH increased from 1.9% to 2.8%, while mortality rate decreased during the study period (1991-2000). Logistic regression showed that hysterectomy, hypertensive disorders, abruption, transverse caesarean delivery, and classical caesarean delivery, increased risk for PPH mortality, while manual placental extraction, episiotomy, and laceration repairs decreased risk. Two geographical regions, Inland Empire and Orange County, were associated with increased PPH mortality, despite having lower incidence of PPH. Teaching status and investor ownership of hospitals increased the risk of PPH mortality. There was no associated change in mortality based on hospital quality rating.

Gefitinib treatment in hormone-resistant and hormone receptor-negative advanced breast cancer

BACKGROUND

Acquired and de novo endocrine resistance in breast cancer (BC) may be associated with overexpression of epidermal growth factor receptor (EGFR). Gefinitib is an orally active selective EGFR inhibitor which might benefit advanced breast cancer (ABC) patients either with acquired hormone resistance or with hormone receptor (HR)-negative tumors.

PATIENTS AND METHODS

A two-arm multicenter phase II trial of oral gefitinib 500 mg/day was planned in two groups of 45 patients with ABC for whom chemotherapy was not currently indicated. Group 1 had hormone-resistant BC defined as HR-positive BC with progression after treatment with tamoxifen and an aromatase inhibitor. Group 2 had HR-negative BC. Tumor response was assessed every 8 weeks. The primary end point was the clinical benefit rate (CBR).

RESULTS

Forty patients with hormone-resistant BC had a CBR of 0%. Two of 25 HR-negative BC patients showed stable disease (less than a 50% reduction and less than a 25% increase in the sum of the products of two perpendicular diameters of all measured lesions and the appearance of no new lesions) at 24 weeks resulting in a CBR of 7.7% (95% CI 0.9% to 25.1%). Enrollment ceased due to the low CBR. Toxicity resulted in treatment interruption (46%), dose reduction (20%) and withdrawal (11%) of patients.

CONCLUSION

At a dose of 500 mg/day, gefitinib monotherapy resulted in a low CBR and no tumor response was identified.

Long-term outcomes of patients with localized rectal cancer treated with chemoradiation or radiotherapy alone because of medical inoperability or patient refusal

PURPOSE

The standard management of rectal cancer continues to be defined by the results of randomized, clinical trials exploring the optimal timing and use of adjuvant chemotherapy and radiation therapy in relation to surgery. The patient with rectal cancer who is elderly and/or has significant comorbidities and the patient who refuses surgery are clinical contexts for which there is limited current data to guide decision making.

METHODS

A retrospective analysis was performed at six Australian centers of patients with rectal cancer treated with radiation therapy or chemoradiation alone because of excessive operative risk or patient refusal of surgery.

RESULTS

We identified 48 patients treated between August 1998 and June 2005 with a median age of 76 (range, 49-94) years. Twenty-four patients (50 percent) were considered medically inoperable and 24 patients refused surgery. Treatment was with chemoradiation (with 5-fluorouracil) in 36 patients and radiotherapy alone in 12 patients; 93 percent completed the planned therapy. A clinical complete response was seen in 56 percent and a partial response in 30 percent of patients. At a median follow-up of 49 months, 18 patients have disease progression, including 10 of 24 in the medically inoperable group and 8 of 24 in the refused surgery group. Of the 25 deceased patients, 16 died from progressive disease and 9 from noncancer causes.

CONCLUSIONS

Chemoradiation or radiotherapy alone is a safe alternative that results in significant progression-free and overall survival times in patients who are considered medically inoperable or refuse to undergo surgery. Ultimately, however, many patients will progress.

A multicentre analysis of the long-term outcomes of patients with localized rectal cancer treated with chemotherapy and/or radiotherapy alone due to medical inoperability or patient refusal

3633

Background: The outcome for patients with localized rectal cancer treated with chemoradiotherapy (CMT) or radiotherapy alone (RT) and no planned subsequent surgery is unknown. Insights can be provided by study of patients that do not undergo surgery due to excessive operative risk (medically inoperable) as a result of advanced age and/or co-morbidities, or patient refusal. Methods: A retrospective analysis at 6 Australian centers. Patients with recurrent rectal cancer, metastatic disease or primary tumors that were considered unresectable were excluded from the study. Results: We identified 48 patients treated between August 1998 and June 2005 meeting our criteria. There were 13 females and 35 males with a median age of 76 years (range 49 - 94). 24 patients (50%) were deemed medically inoperable and 24 patients refused surgery (the most common reasons were the desire to avoid a stoma or fear of surgery). Treatment was with standard long course radiation plus 5-FU (either bolus or continuous infusion) in 36 patients (75%) and 12 (25%) received RT alone. A complete clinical response was documented in 23 patients (48%) and a partial clinical response was documented in 14 patients (30%). At a median follow-up of 49 months, 18 patients (37.5%) have documented disease progression including 10 of 24 in the medically inoperable group and 8 of 24 in the refused surgery group. The median progression-free survival for all patients was 30+ months. 7 had local progression only, 7 had distant progression only and 4 patients had both local and distant progression. Of the 23 deceased patients, 16 (70%) died from progressive disease and 7 (30%) from non-cancer causes, including 4 from the refused surgery group. The median survival for all patients was 35 + months. Conclusions: In patients who are not suitable candidates for surgical resection due to advanced age and/or comorbidity CRT or RT alone is a safe alternative that results in significant progression-free and overall survival times, with many patients succumbing to co-morbidities rather than progressive disease. Many of these patients refusing surgery will have long periods of disease control after treatment with CRT or RT.

No significant financial relationships to disclose.

The use of mycophenolate mofetil suspension in pediatric renal allograft recipients

Mycophenolate mofetil (MMF) is widely used to prevent acute rejection in adults after renal, cardiac, and liver transplantation. This study investigated the safety, tolerability, and pharmacokinetics of MMF suspension in pediatric renal allograft recipients. One hundred renal allograft recipients were enrolled into three age groups (33 patients, 3 months to <6 years; 34 patients, 6 to <12 years; 33 patients, 12 to 18 years). Patients received MMF 600 mg/m2 b.i.d. concomitantly with cyclosporine and corticosteroids with or without antilymphocyte antibody induction. One year after transplantation, patient and graft survival (including death) were 98% and 93%, respectively. Twenty-five patients (25%) experienced a biopsy-proven (Banff grade borderline or higher) or presumptive acute rejection within the first 6 months post-transplantation. Analysis of pharmacokinetic parameters for mycophenolic acid (MPA) and mycophenolic acid glucuronide showed no clinically significant differences among the age groups. The dosing regimen of MMF 600 mg/m2 b.i.d. achieved the targeted early post-transplantation MPA 12-h area under concentration-time curve (AUC0-12) of 27.2 microg h per ml. Adverse events had similar frequencies among the age groups (with the exception of diarrhea, leukopenia, sepsis, and anemia, which were more frequent in the <6 years age group) and led to withdrawal of MMF in about 10% of patients. Administration of MMF 600 mg/m2 b.i.d. is effective in prevention of acute rejection, provides predictable pharmacokinetics, and is associated with an acceptable safety profile in pediatric renal transplant recipients.

NF-kappaB signaling pathway governs TRAIL gene expression and human T-cell leukemia virus-I Tax-induced T-cell death

The Tax oncoprotein encoded by human T-cell leukemia virus induces both T-cell activation and apoptosis. The mechanism by which Tax induces apoptosis has remained unclear. Using genetically manipulated T-cell lines, we demonstrate that Tax-induced T-cell death is dependent on NF-kappaB signaling. Tax fails to induce apoptosis in T cells lacking IkappaB kinase gamma (IKKgamma), an essential component of the NF-kappaB signaling pathway. This defect was rescued when the mutant cells were reconstituted with exogenous IKKgamma. We further demonstrate that the Tax-induced T-cell death is mediated by TNF (tumor necrosis factor)-related apoptosis-inducing ligand (TRAIL), because this event can be effectively inhibited by a TRAIL-blocking antibody. Consistent with this functional aspect, Tax stimulates the expression of TRAIL mRNA. Finally, we provide genetic evidence demonstrating that the NF-kappaB signaling pathway is essential for TRAIL gene induction by both Tax and T-cell activation signals. These studies reveal a novel function of the NF-kappaB signaling pathway and suggest a key mechanism by which Tax induces T-cell death.

Activation by IKKalpha of a second, evolutionary conserved, NF-kappa B signaling pathway

In mammals, the canonical nuclear factor kappaB (NF-kappaB) signaling pathway activated in response to infections is based on degradation of IkappaB inhibitors. This pathway depends on the IkappaB kinase (IKK), which contains two catalytic subunits, IKKalpha and IKKbeta. IKKbeta is essential for inducible IkappaB phosphorylation and degradation, whereas IKKalpha is not. Here we show that IKKalpha is required for B cell maturation, formation of secondary lymphoid organs, increased expression of certain NF-kappaB target genes, and processing of the NF-kappaB2 (p100) precursor. IKKalpha preferentially phosphorylates NF-kappaB2, and this activity requires its phosphorylation by upstream kinases, one of which may be NF-kappaB-inducing kinase (NIK). IKKalpha is therefore a pivotal component of a second NF-kappaB activation pathway based on regulated NF-kappaB2 processing rather than IkappaB degradation.

The ability of an oligomeric human immunodeficiency virus type 1 (HIV-1) envelope antigen to elicit neutralizing antibodies against primary HIV-1 isolates is improved following partial deletion of the second hypervariable region

Partial deletion of the second hypervariable region from the envelope of the primary-like SF162 virus increases the exposure of certain neutralization epitopes and renders the virus, SF162DeltaV2, highly susceptible to neutralization by clade B and non-clade B human immunodeficiency virus (HIV-positive) sera (L. Stamatatos and C. Cheng-Mayer, J. Virol. 78:7840-7845, 1998). This observation led us to propose that the modified, SF162DeltaV2-derived envelope may elicit higher titers of cross-reactive neutralizing antibodies than the unmodified SF162-derived envelope. To test this hypothesis, we immunized rabbits and rhesus macaques with the gp140 form of these two envelopes. In rabbits, both immunogens elicited similar titers of binding antibodies but the modified immunogen was more effective in eliciting neutralizing antibodies, not only against the SF162DeltaV2 and SF162 viruses but also against several heterologous primary HIV type 1 (HIV-1) isolates. In rhesus macaques both immunogens elicited potent binding antibodies, but again the modified immunogen was more effective in eliciting the generation of neutralizing antibodies against the SF162DeltaV2 and SF162 viruses. Antibodies capable of neutralizing several, but not all, heterologous primary HIV-1 isolates tested were elicited only in macaques immunized with the modified immunogen. The efficiency of neutralization of these heterologous isolates was lower than that recorded against the SF162 isolate. Our results strongly suggest that although soluble oligomeric envelope subunit vaccines may elicit neutralizing antibody responses against heterologous primary HIV-1 isolates, these responses will not be broad and potent unless specific modifications are introduced to increase the exposure of conserved neutralization epitopes.

[New species of Anolis (Sauria: Iguanidae) from the north region of eastern Cuba]

A new Anolis species of the Alpha section from the north region of eastern Cuba (Holguín province) is described. It differs from all Cuban species of Anolis in its green coloration with greenish gray bands on body, legs and tail, in having subtriangular mental scales as well as in other details of color and scutellation. This new species is most closely related to A. isolepis but it can be distinguished from both, A. i. isolepis and A. i. altitudinalis, by its coloration and pattern, the larger body size, the presence of smooth ventral scales (similar in size to the dorsal scales) and by the absence of enlarged postcloacal scales in the male.

Laboratory and field studies on the effects of the antibiotic tylosin on honey bee Apis mellifera L. (Hymenoptera: Apidae) development and prevention of American foulbrood disease

Laboratory and field studies were conducted to determine the effectiveness of the antibiotic tylosin in preventing and controlling infections of American foulbrood disease (AFB) of honey bees. Studies conducted on immature worker bees maintained in the laboratory revealed that honey bee larvae could tolerate quite a range of doses of antibiotic in their diet. Intermediate doses of tylosin protected very young larvae from becoming infected by Bacillus larvae at a concentration of 1.5 x 10(8) spores/ml of diet. Antibiotic treatment had no measurable effects on larval or pupal developmental rates until the dose reached a lethal level. Bees in field colonies readily consumed tylosin in powered sugar, up to a level of 800 mg/7 g sugar. No negative colony effects were noted at any dosage rates. Protection against infection by American foulbrood was compared to results obtained with 200 mg Terramycin, the standard dose of the only substance currently registered for foulbrood control. Both 200 mg Terramycin and 100 mg tylosin protected the colonies for up to 3 weeks. A 200-mg dose of tylosin protected the colony for an additional week. Doses of 100 mg or more of tylosin were adequate to eliminate signs of AFB infection in overtly diseased colonies.

Near-infrared measurement of relative and absolute humidity through detection of water adsorbed on a silica gel layer

Near-IR spectroscopy is especially well suited to moisture determination because of the relatively high absorptivity of water compared to most other substances. In the present work, near-IR diffuse-transmittance spectroscopy is applied to the measurement of humidity via observation of adsorbed water on a high-performance thin-layer chromatography silica gel plate. The adsorbed water is detected through both ordinary absorption of radiation by water molecules and the increased scattering of near-IR radiation by the silica gel as it adsorbs more water. This technique shows promise as a highly accurate and sensitive humidity sensor with a time constant of less than 1 min. The addition of inorganic salts to the silica gel layer is shown to increase the response to water vapor. However, it also increases the time constant of the sensor. A miniature humidity sensor using a commercially available near-IR transmissive switch is also demonstrated. Possible interferences and hysteresis effects are investigated.

Characterization of kappa opioid receptors in the rabbit ear artery

Quantitative characterization of the kappa opioid receptor in the rabbit ear artery was carried out using three kappa-selective agonist compounds, dynorphin-(1-13), U-69593 and ethylketocyclazocine. Kinetic analysis was performed using the antagonist, MR 2266. Two other in vitro preparations were studied for comparison: the mouse was deferens and rabbit was deferens. To avoid mu receptor action in the mouse was deferens the irreversible mu receptor antagonist, beta-funaltrexamine, was used. It was demonstrated that, using the highly selective kappa agonist compound U-69593, Ke values for MR 2266 obtained in the three assay systems were not significantly different. These results suggest that kappa receptors present in these three tissues share identical properties.

Relationship between increased vascular permeability and extravascular albumin clearance in rabbit inflammatory responses induced with Escherichia coli

Intradermal injections of killed Escherichia coli are known to cause a variety of pathophysiological changes in the microcirculation that facilitate the extravasation of plasma constituents into the interstitium. In an attempt to learn more of the factors that regulate the magnitude and duration of inflammatory edema, we have focused on the relationship between the extravasation of protein into the interstitium and the removal of extravascular protein from the lesion sites. Vascular permeability changes have been assessed by the local accumulation of systemically administered [131I] or [125I]-albumin and extravascular protein clearance measured by monitoring the disappearance of [125I]-albumin from the same sites. Radioactivity was quantitated with an external gamma-scintillation probe or by punching out the lesion sites in sacrificed animals and counting in a gamma-spectrometer. Scintillation probe measurements of the net accumulation of intravenously administered [125I]-albumin in E. coli-induced skin lesions revealed that the extravasation of albumin was greater than the clearance of protein from the same sites. Comparisons of the removal rates of albumin injected directly into the E. coli sites revealed that, despite increases in vascular permeability amounting to 170 to 700% of control values, the mobilization of deposited albumin was no greater than that from control tissues that received saline; in fact with high concentrations of E. coli (10(8) injected/site) the mobilization of protein from the lesions was significantly reduced. The systemic administration of 055:B5 endotoxin (0.3, 1.6, or 3.3 micrograms/kg) also suppressed the clearance of albumin from skin. In contrast to these results, 300 to 1500% increases in vascular permeability induced with other inflammatory stimuli including thermal injury, high concentrations of bovine serum albumin, or bradykinin, resulted in enhanced clearance of extravascular protein from lesion or injection sites. These experiments suggest that an inability to effectively mobilize extravascular protein from the inflammatory focus could be a major contributing factor in regulating edema in inflammatory reactions induced with E. coli and may possibly contribute to the edema associated with septicemia.

Filaria in the vitreous of the eye of man in peninsular Malaysia

An active worm was seen in the right eye of a 62-year-old man in Malaysia. The worm was behind the lens and attached at one end to some vitreous fibers. It was tentatively identified as an immature Dirofilaria immitis. There appear to be only five previous authentic reports of filariae in the vitreous.

Accuracy of numerical coronary profile. Correlation of risk factors with arteriographically documented severity of atherosclerosis

We compared a coronary risk profile (developed by the Framingham Study) based on age, sex, cigarette smoking, glucose intolerance, left ventricular hypertrophy, systolic blood pressure and serum cholesterol to angiographically determined severity of coronary-artery disease in 158 consecutive patients undergoing cardiac catheterization. A profile of 1.0 indicated average relative risk. Risk profiles for 105 patients with angiographically documented coronary-artery disease was 1.52 whereas it was 1.08 for the group without coronary disease (P less than 0.01). There was no difference between the patients with coronary disease with (1.44) and those without previous infarct (1.46). The coronary risk profile, however, increased with increasing severity of coronary disease. The high-risk coronary patient can be identified by seven easily measured risk factors, and the extent of coronary-artery disease increases with the number and severity coronary risk factors.