Persistence of ibrutinib-associated hypertension in CLL pts treated in a real-world experience

7525

Background: Cardiovascular (CV) complications associated with ibrutinib (Ibr) include hypertension (HTN) and atrial fibrillation (AFIB) (incidence 26% and 9%, OBrien, ASH 2016). Unlike clinical trials, Ibr toxicities are the most common reasons for its discontinuation in clinical practice. The incidence of HTN in pts treated with Ibr outside of clinical trial setting and its impact on outcomes is unknown. Methods: Retrospective, cohort study of Ibr-treated CLL pts to estimate HTN incidence. Baseline CLL characteristics and co-morbidities were recorded. Blood pressure (BP) measurements were recorded prior to Ibr and sequentially following exposure at specific time points. CV meds were reviewed during a 12 mo follow-up period. The association between Ibr exposure and BP was tested. Results: 153 consecutive CLL pts treated with Ibr at a dose of 420 mg/day were identified. Med age was 57 yr (range: 34-87), relapsed CLL (69%), follow-up 14.5 mo. CV pre-Ibr characteristics included: smoking hx (49%), HTN (42%), hyperlipidemia (39%), diabetes (17%), CAD (12%), AFIB (6.8%). Proportion of pts on ≥1 anti-HTN med increased from 44% pre-Ibr (20% ≥ 2) to 57% during Ibr (30% ≥ 2). Med pre-Ibr BP was 127/70 mmHg (range 90-182/48-95mmHg). At 1, 3, 6, 9, 12 mo, med BPs were 137/73, 141/75, 143/76, 140/75, 142/77 (7 mo to peak BP). There was a significant association between Ibr exposure and increased BP (p<.01). New HTN was observed in 40% of pts and 36% HTN pts had BP increased above baseline (med baseline 135/70 vs peak 161/80). Incidence of new AFIB was 8.1%. In UV analyses, predictive clinical factors for HTN were not identified. Pre-Ibr HTN (OR 3.0, p .05), CAD (OR 4.3, p .03), prior AFIB event (OR 10.8, p.001), hyperlipidemia (OR 3.4, p.05) were associated with post-Ibr AFIB. Conclusions: In the largest real-world series focused on BP in Ibr treated pts, we demonstrate a clear association between Ibr and HTN. Nearly 40% of pts developed HTN within 12 mo of Ibr exposure (vs. 26% in clinical trials over 5 yr). Despite aggressive management (multiple agents), Ibr associated HTN was persistent. These data underscore the critical need for monitoring and management strategies for HTN and follow-up data on future CV events.

Clinical outcomes of DLBCL, follicular lymphoma (FL) and Richter transformation (RT) patients treated with ibrutinib: A real-world experience of off-label ibrutinib use

e19043

Background: Ibrutinib (IBR), a BTK inhibitor, is FDA approved for CLL, Waldenstrom macroglobulinemia, marginal zone lymphoma and mantle cell lymphoma. Despite limited data, IBR is being utilized as a therapy for patients (pts) with relapsed/refractory (RR) DLBCL and FL. In an effort to further characterize the efficacy of IBR in these settings, we conducted a retrospective cohort study of IBR-treated pts with DLBCL, RT or FL. Methods: A retrospective cohort study of DLBCL, RT and FL pts treated with IBR was completed. Data collected included demographics, stage, IPI, prior treatments, IBR dose/duration, reasons for discontinuation, and response. PFS and OS were estimated using the Kaplan Meier method. Results: 44 pts were identified (DLBCL: n = 24, 55%; FL: n = 12, 27%; RT: n = 8, 18%). Baseline characteristics: age (range 19 – 80), 61% male, 95% ECOG 0 - 1, 71% stage IV, 62% elevated LDH, 48% R-IPI ≥ 4. DLBCL subtypes (Hans criteria) were 46% non-GC (n = 11), 29% GC (n = 7), 25% unclassifiable (n = 6). In FL, 8% were grade 1, 59% grade 2, and 33% grade 3a. Med number of prior therapies was 5 (range 1-11). Most common reasons for IBR discontinuation were progression (35%), toxicity (20%), bridge to CAR-T (10%). PFS and OS data are shown in the table below. In DLBCL, cell of origin (Hans) did not impact outcomes (p = .97, LR test). PFS was superior in RT as compared to DLBCL (p = .03, LR test). Conclusions: In the largest single-center, real-world experience of IBR use in DLBCL, RT and FL, we validate findings reported in clinical trials. In FL, responses appear to be durable (median PFS > 10 months). Outcomes are poor in DLBCL and use of IBR as monotherapy is not recommended. Perhaps IBR is best used as a short-term bridge to more definitive therapies. Cell of origin (Hans) may not predict PFS and should not be used to select pts for IBR. Pts with RT appear to have more durable responses (vs. DLBCL) suggesting differing dependence on BTK signaling. [Table: see text]

Abstract P1-12-08: The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies

Background: Human epidermal growth factor receptor 2 (HER2) is over-expressed in approximately 20 - 30% of breast cancers. HER2-positive breast cancers frequently metastasize to the brain. In recent years, many new drugs have been approved for HER2-positive metastatic breast cancer (MBC). In the metastatic setting, trastuzumab was approved in 2000, lapatinib 2007, and pertuzumab and ado-trastuzumab emtansine in 2012. We sought to describe the incidence, time course, and prognostic factors of BM in patients (pts) with HER2+ MBC during the time when dramatic changes in systemic therapy occurred.

Patients/methods: The study included pts with HER2-positive MBC treated at two academic hospitals: Dana Farber Cancer Institute (DFCI) (2000-2007 [DFCI-T1], 2008-2011 [DFCI-T2]) and University of North Carolina (UNC) (2012-2014). We examined the incidence of BM (at diagnosis [dx] and within 1-2 years of MBC dx). We combined the two cohorts to examine outcomes – time to BM, survival following MBC, and survival following BM – using the Kaplan Meier method and Cox regression modeling.

Results: We identified 185 (DFCI n=128, 97 diagnosed 2000-2007 and 31 diagnosed 2008-2011; UNC n=57, all diagnosed 2012-2014) pts with HER2-positive MBC. Through a median of 4 years follow-up after the MBC dx (min 2, max 11), 118 had died and 67 were censored. The median age at MBC dx was 52 (min 25, max 88), 149 (82%) were Caucasian, 88 (48%) had hormone receptor (HR) positive BC, and 67 (37%) had de-novo (i.e., non-recurrent) MBC. BM was present at the MBC dx for 8% of pts in DFCI-T1, 16 % of pts in DFCI-T2, and 16% of pts at UNC. Within 1 year of the MBC dx, BM was present in 21% of DFCI-T1, 29% in DFCI-T2, 23% of UNC pts. Within 2 years of the MBC dx, 67 (36%) pts had developed BM, of which one third (22) were diagnosed at initial MBC presentation. In unadjusted analyses, there were no differences in time to BM dx by age (p=0.2), race (p=0.1) or HR status (p=0.1). The median survival following the development of BM for all pts was 1.5 years. A multivariable model predicting survival after the MBC dx, found factors associated with shorter survival included having (vs. not having) BM at the initial MBC dx, having received (vs. not having received) adjuvant HER2-directed therapy prior to the MBC dx, and having recurrent (vs. de novo) MBC (P≤0.02 for all). Age, HR status, race and time period of MBC dx were not significant in the multivariable model.

Conclusions: Among pts diagnosed in the modern era, after new therapies became available, BM remains a common problem for pts with HER2-positive MBC. While no obvious trends in the incidence of HER2-positive MBC are suggested, conclusions regarding incidence trends should be considered hypothesis-generating until larger, population-based data become available. Nevertheless, a dx of BM early in the course of MBC treatment and prior receipt of adjuvant trastuzumab appeared to confer a more aggressive disease course. Coordinated, prospective collection of the incidence and outcomes of BM among pts with HER2-positive MBC, studies of pts who develop BM &gt;2 years after their MBC dx, and clinical trials of treatment strategies for pts with trastuzumab-resistant BM are needed.

Citation Format: Strulov Shachar S, Deal AM, Vaz-Luis I, Dees EC, Carey LA, Hassett MJ, Garrett AL, Benbow JM, Hughes ME, Mounsey L, Lin N, Anders CK. The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-12-08.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2014

Collections of Puccinia triticina obtained from wheat fields and breeding plots in the Great Plains, Ohio River Valley, and southeastern states, were tested for virulence in 2014 in order to determine the virulence of the wheat leaf rust pathogen population in the United States. Single uredinial isolates (380 total) were derived from the collections and tested for virulence phenotype on 20 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes. In 2014, 55 virulence phenotypes were described in the United States. Virulence phenotypes MBTNB, TBBGS, and TCRKG were the three most common phenotypes. Phenotypes MBTNB and TCRKG are both virulent to Lr11, and TCRKG is also virulent to Lr18 and Lr26. MBTNB and TCRKG were most common in the soft red winter wheat region of the southeastern states and the Ohio Valley. Phenotype TBBGS is virulent to Lr39, which is present in the hard red winter wheat cultivars, and Lr21, which is present in the hard red spring wheat cultivars. Isolates with virulence to Lr11, Lr18, and Lr26 were most common in the southeastern states and Ohio Valley region. Isolates with virulence to Lr21 and Lr39 were most common in the hard red wheat region of the southern and northern Great Plains.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2013

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by USDA-ARS personnel and cooperators in the Great Plains, Ohio River Valley, and southeastern states in order to determine the virulence of the wheat leaf rust population in 2013. Single uredinial isolates (490 total) were derived from the collections and tested for virulence phenotype on 20 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes. In 2013, 79 virulence phenotypes were described in the United States. Virulence phenotypes MBTNB, TNBGJ, and MCTNB were the three most common phenotypes. Phenotypes MBTNB and MCTNB are both virulent to Lr11, and MCTNB is virulent to Lr26. MBTNB and MCTNB were most common in the soft red winter wheat region of the southeastern states and Ohio Valley. Phenotype TNBGJ is virulent to Lr39/41 and was widely distributed throughout the hard red winter wheat region of the Great Plains. Isolates with virulence to Lr11, Lr18, and Lr26 were common in the southeastern states and Ohio Valley region. Isolates with virulence to Lr21, Lr24, and Lr39/41 were frequent in the hard red wheat region of the southern and northern Great Plains.

Lack of a significant pharmacokinetic interaction between maraviroc and tacrolimus in allogeneic HSCT recipients

OBJECTIVES

Emerging data suggest that the combination of tacrolimus and the CCR5 antagonist maraviroc, both cytochrome P450-3A4 substrates, may be effective in preventing graft-versus-host disease in patients undergoing allogeneic HSCT. This study evaluated whether a pharmacokinetic interaction exists between these agents.

METHODS

The study included 36 allogeneic HSCT recipients who received maraviroc + tacrolimus and 43 recipients of tacrolimus alone. We used a difference-in-differences analysis to examine the change in the concentration/dose ratios of tacrolimus after the discontinuation of maraviroc. In addition, we analysed the concentrations and dose requirements of tacrolimus in the two groups.

RESULTS

There was no significant difference in tacrolimus concentration/dose ratios in patients receiving maraviroc + tacrolimus compared with tacrolimus alone. Upon discontinuation of maraviroc, the change in concentration/dose ratio was small and not significant relative to the control group, and the effect estimate was further attenuated after adjustment for confounders [-0.35 (ng/mL)/(mg/day); P = 0.46]. In addition, the change in mean tacrolimus dose after discontinuation of maraviroc was similar between the groups (0.12 mg/day; P = 0.56), as was the change in mean tacrolimus concentration (0.02 ng/mL; P = 0.97).

CONCLUSIONS

Our findings do not support a significant inhibitory effect of maraviroc on the metabolism of tacrolimus. These data demonstrate that this drug combination is safe and imply that the protective effect of maraviroc against graft-versus-host disease was not mediated through an increase in tacrolimus concentrations. These findings are important for the design of clinical trials that evaluate maraviroc in combination with cytochrome P450-3A4 substrates.

Carbodiimide induced cross-linking, ligand addition, and degradation in gelatin

The water-soluble carbodiimide, 1-ethyl-3-(3-(dimethylaminopropyl)-carbodiimide (EDC) is widely used in protein chemistry. We used EDC-induced gelatin cross-linking as a model for amide bond formation to resolve reaction ambiguities with common variables of buffers, gelatin concentration, and pH. Percentage changes in SEC high molecular weight peak areas were used to follow the reactions. Differences in reaction rate and extent were observed with four commonly used buffers, while differences in extent were observed for commonly used concentrations and pH. We also investigated an anhydride mechanism for aqueous EDC-induced amide bond formation that has received little attention since its proposal in 1995. Gelatin carboxyl groups had a synergistic role during the addition of hydrazine to corroborate the anhydride formation between carboxyl groups. EDC-induced degradation of gelatin was investigated using percentage changes in SEC low molecular weight peak areas. The degradation occurred in excess EDC at neutral to alkaline pH and was enhanced substantially when reacting amino groups were not available. A mechanism of EDC-induced gelatin degradation is proposed and designated the extended Khorana mechanism. This EDC side reaction has the potential to occur in peptides and proteins under similar conditions.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2012

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by United States Department of Agriculture-Agricultural Research Service personnel and cooperators in the Great Plains, Ohio River Valley, southeastern states, and Washington State and Idaho in order to determine the virulence of the wheat leaf rust population in 2012. Single uredinial isolates (501 in total) were derived from the collections and tested for virulence phenotype on 20 lines of 'Thatcher' wheat that are near-isogenic for leaf rust resistance genes. In 2012, 74 virulence phenotypes were described in the United States. Virulence phenotypes TNBGJ, TCRKG, and MBTNB were the three most common phenotypes. Phenotype TNBGJ is virulent to Lr39/41 and was widely distributed throughout the hard red winter wheat region of the Great Plains. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and was found mostly in the soft red winter wheat region in the eastern United States. Phenotype MBTNB is virulent to Lr11 and was also found mostly in the soft red winter wheat region. The frequency of isolates with virulence to Lr39/41, which is present in many hard red winter wheat cultivars in the Great Plains region, continued to increase. Isolates with virulence to Lr21, which is present in many hard red spring wheat cultivars, also continued to increase in frequency in the northern Great Plains region.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2011

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by USDA-ARS personnel and cooperators in the Great Plains, Ohio River Valley, southeastern states, Oregon, and Washington State in order to determine the virulence of the wheat leaf rust population in 2011. Single uredinial isolates (440 total) were derived from the collections and tested for virulence phenotype on 18 lines of Thatcher wheat and a winter wheat line that are near-isogenic for 19 leaf rust resistance genes. In 2011, 87 virulence phenotypes were described in the United States. Virulence phenotypes TBBGJ, MLDSD, and TCRKG were the three most common phenotypes. Phenotype TBBGJ is virulent to Lr39/41 and was widely distributed throughout the hard red winter wheat region of the Great Plains. Phenotype MLDSD is virulent to Lr17 and Lr39/41 and was widely distributed throughout the United States. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and was found mostly in the soft red winter wheat region in the eastern United States. Isolates with virulence to Lr39/41 and avirulence to Lr9 were prevalent in the Great Plains region for the first time. Virulence to Lr21 was present in five virulence phenotypes mostly from the spring wheat region of the northern Great Plains.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2010

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by United States Department of Agriculture-Agricultural Research Service personnel and cooperators in the Great Plains, Ohio River Valley, southeastern states, Oregon, and Washington State in order to determine the virulence of the wheat leaf rust population in 2010. Single uredinial isolates (537 total) were derived from the collections and tested for virulence phenotype on 19 lines of 'Thatcher' wheat and a winter wheat line that are near-isogenic for 20 leaf rust resistance genes. In 2010, 38 virulence phenotypes were described in the United States. Virulence phenotypes MLDSD, TDBJG, and TCRKG were the three most common phenotypes. Phenotype MLDSD is virulent to Lr17 and Lr39/Lr41 and was widely distributed throughout the United States. Phenotype TDBJG is virulent to Lr24 and was found in both the soft red winter wheat and hard red winter wheat regions. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and was found mostly in the soft red winter wheat region in the eastern United States. Virulence to Lr21 was found for the first time in North America in isolates collected from spring wheat cultivars in North Dakota and Minnesota.

P1-11-02: Racial/Ethnic Differences in Adjuvant Trastuzumab Receipt for Women with Breast Cancer within the National Comprehensive Cancer Network

Background Racial/ethnic disparities in breast cancer care are well documented. Although adjuvant trastuzumab has been shown to improve disease outcomes for women with Human Epidermal Growth Factor Receptor 2 (HER2)-positive cancers, the ‘real world’ utilization and toxicity of adjuvant trastuzumab are unknown. Because therapy involves one year of treatment and the costs of treatment are high, a risk for treatment disparity exists. We examined differences in receipt and completion of adjuvant trastuzumab by race/ethnicity, education, employment, and insurance for women diagnosed with HER2−positive breast cancer.

Methods Using the National Comprehensive Cancer Network (NCCN) Breast Cancer Outcomes Database, we identified 1,146 women with stage I-III HER-2 positive breast cancer who presented to participating NCCN institutions during 2005–2008. In multivariable logistic analyses, we assessed the effect of race/ethnicity on the likelihood of trastuzumab therapy, and among women who initiated trastuzumab, the likelihood of completing ≥ 270 days of therapy, adjusting for center, diagnosis year, age, insurance, comorbidity, education, employment, and tumor characteristics. We also examined reasons for discontinuation of therapy among those who stopped treatment prematurely.

Results Among patients eligible for this analysis, 75% women were Caucasian, 9% were African-American, and 9% were Hispanic. Most women had managed care insurance (71%) and were employed/student (52%). About one-third (36%) had a college degree and 39% had a high school education or less. Overall, most women (82%) received neo/adjuvant trastuzumab and there were no racial/ethnic differences in receipt of therapy (adjusted odds ratio [OR] 1.11, 95% confidence interval [CI] .72-1.71 for African-American and OR 1.39, 95% CI .76-2.54 for Hispanic, versus Caucasian women). Among the 769 women who initiated neo/adjuvant trastuzumab and had ≥ 365 days of follow-up, 84% completed ≥ 270 days of trastuzumab. Rates of completion were lower for African-American (72%) and Hispanic (82%) women than Caucasian women (85%). In adjusted analyses, African-American women but not Hispanic women had lower odds of completing therapy compared with Caucasian women (OR .45, 95% CI .29-.70, p=0.0003). Indemnity insurance (versus managed care) was associated with lower odds of trastuzumab completion, as was having a high school education or less (versus college education). Among the 123 women who did not complete trastuzumab, 26% stopped early for toxicity, and this occurred more frequently for African-American women than Caucasian women (50% vs. 21%), but small sample precluded a meaningful test for statistical significance.

Conclusion: Compared with Caucasian women, African-American women had similar rates of initiation of adjuvant trastuzumab but much lower rates of completion that were not explained by differences in education, employment, or insurance. Because of the significant benefits conferred by adjuvant trastuzumab therapy for HER2−positive breast cancer, interventions to assure completion of therapy could lead to improved outcomes. Further exploration of racial differences in toxicity and tolerance of therapy are also warranted.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-11-02.

P1-08-05: Age and Survival in Women with Early Stage Breast Cancer: An Analysis Controlling for Tumor Subtype

Background: Previous research has suggested that young age at diagnosis is an independent risk factor for breast cancer recurrence and death in women with early stage breast cancer. However, young women are more likely to have aggressive subtypes of breast cancer. No prior studies have adequately controlled for tumor phenotype, including HER-2/neu (HER2) status, in particular. Recent evidence has suggested that the prognostic effect of young age varies by tumor subtype.

Methods: We examined data from women with newly diagnosed Stage 1–3 breast cancer presenting to one of 8 NCCN centers between January 2000 and December 2007. Multivariate Cox proportional hazards models were used to assess the relationship between age and breast cancer specific survival, controlling for known prognostic factors and treatment. In addition, we conducted stratified analyses by estrogen receptor (ER) and HER2 status.

Results: 19,633 women with Stage 1–3 breast cancer eligible for analysis including 2,177 (11%) who were age 40 years or younger at diagnosis. Younger women were more likely to be non-white or Hispanic, more educated, employed, and to have higher stage, high grade, ER-negative, progesterone receptor (PR) negative, and HER2−positive disease, and treated with chemotherapy and trastuzumab (all variables P&lt; 0.0001 by Chi-Square test). 5-year survival among younger women was 94.1 (95% Confidence Interval [CI] 92.9−95.3) and 96.3 (95% CI 95.9−96.6) for older women. In a multivariate Cox proportional hazards model controlling for sociodemographic, disease, and treatment characteristics, women age &lt; 40 or younger at diagnosis had increased mortality compared to older women (Hazard Ratio [HR] 1.26, 95% CI 1.02−1.56). In stratified analyses, age 40 or less was associated with increased mortality among women with ER-positive disease (HR 1.44, 95% CI 1.01−2.05), but was not among those with ER-negative disease (HR 1.15, 95% CI 0.85−1.55). Younger age was associated with a statistically significant increase in mortality among women with HER2−negative disease (HR 1.29, 95% CI 1.00−1.68), but this difference did not reach statistical significance among those with HER2−positive disease (HR 1.30, 95% CI 0.82−2.09). Conclusions: The effect of age on short-term survival of women with early breast cancer appears to vary by breast cancer subtype, particularly ER status. Further research to elucidate differences in breast cancer biology and efficacy of therapy within tumor types by age is warranted.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-05.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2009

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from surveys of wheat (Triticum aestivum) fields and wheat breeding plots by United States Department of Agriculture-Agricultural Research Service personnel in the Great Plains, Ohio River Valley, southeast, California, and Washington State in order to determine the virulence of the wheat leaf rust population in 2009. Single uredinial isolates (591 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3a, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17a, Lr30, LrB, Lr10, Lr14a, Lr18, Lr21, and Lr28 and a winter wheat line with Lr39/41. Forty-one virulence phenotypes were described. Virulence phenotypes MLDSD, TCRKG, and TDBGG were the three most common phenotypes. Phenotype MLDSD is virulent to Lr17 and Lr39/Lr41 and was widely distributed throughout the United States. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and is found mostly in the soft red winter wheat region in the eastern United States. TDBGG is virulent to Lr24 and was found in both the soft red winter wheat and hard red winter wheat regions. Virulence to Lr21 was not found in any of the tested isolates. Virulence to Lr11, Lr18, and Lr26 increased in 2009 in the soft red winter wheat regions. Virulence to Lr17 and Lr39/Lr41 increased in the Great Plains region. Two separate epidemiological zones of P. triticina in the soft red winter wheat region of the southern and eastern states and in the hard red wheat region of the Great Plains were described.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2008

Collections of Puccinia triticina were obtained from rust-infected wheat (Triticum aestivum) leaves provided by cooperators throughout the United States and from surveys of wheat fields and wheat breeding plots by USDA-ARS personnel in the Great Plains, Ohio River Valley, Southeast, and Washington State in order to determine the virulence of the wheat leaf rust population in 2008. Single uredinial isolates (730 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, Lr18, Lr21, Lr28, and a winter wheat line with Lr41. Forty-eight virulence phenotypes were described. Virulence phenotypes TDBGG, TCRKG, and MLDSD were the three most common phenotypes. TDBGG is virulent to Lr24 and was found in both the soft red winter wheat and hard red winter wheat regions. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and is found mostly in the soft red winter wheat region in the eastern United States. Phenotype MLDSD is virulent to Lr17 and Lr41 and was widely distributed in the Great Plains. Virulence to Lr21 was not found in any of the tested isolates. Virulence to Lr11 and Lr18 increased in 2008 in the soft red winter wheat regions. Two separate epidemiological zones of P. triticina in the soft red winter wheat region of the southern and eastern states and in the hard red wheat region of the Great Plains were described.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2007

In 2007, leaf rust of wheat was severe throughout the Great Plains region of North America. Yield losses in wheat due to leaf rust were estimated to be 14% in Kansas. Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio River Valley, southeast, California, and Washington State in order to determine the virulence of the wheat leaf rust population in 2007. Single uredinial isolates (868 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3a, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17a, Lr30, LrB, Lr10, Lr14a, Lr18, Lr21, and Lr28, and on winter wheat lines with genes Lr41 and Lr42. Fifty-two virulence phenotypes were found. Virulence phenotypes TDBJG, MFPSC, and TDBJH were among the four most common phenotypes and were all virulent to resistance gene Lr24. These phenotypes were found throughout the Great Plains region. Phenotype MLDSD, with virulence to Lr9, Lr17, and Lr41, was also widely distributed in the Great Plains. In the soft red winter wheat region of the southeastern states, phenotypes TCRKG, with virulence to genes Lr11, Lr26, and Lr18, and MFGJH, with virulence to Lr24, Lr26, and Lr11, were among the common phenotypes. Virulence phenotypes with virulence to Lr16 were most frequent in the spring wheat region of the northern Great Plains. Virulence phenotypes with virulence to Lr11, Lr18, and Lr26 were most common in the soft red winter areas of the southeastern states and Ohio Valley. Virulence to Lr21 was not found in any of the tested isolates.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2006

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio River Valley, southeast, California, and Washington State in order to determine the virulence of the wheat leaf rust population in 2006. Single uredinial isolates (718 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3a, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17a, Lr30, LrB, Lr10, Lr14a, Lr18, Lr2, and Lr28 and winter wheat lines with genes Lr41 and Lr42. In the United States in 2006, 56 virulence phenotypes were found. Virulence phenotypes TDBJG, TDBGG, and TDBJH were among the four most common phenotypes and were all virulent to resistance gene Lr24. These phenotypes were found throughout the Great Plains region. Phenotype MLDSD with virulence to Lr9, Lr17, and Lr41 was also widely distributed in the Great Plains. In the soft red winter wheat region of the southeastern states, phenotypes TCRKG and MBRKG with virulence to genes Lr11, Lr26, and Lr18 were among the common phenotypes. Virulence phenotypes with virulence to Lr16 were most frequent in the spring wheat region of the northern Great Plains. Virulence to Lr21 was not found in any of the tested isolates.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2005

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio River Valley, southeast, California, and Washington State, in order to determine the virulence of the wheat leaf rust population in 2005. Single uredinial isolates (797 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3a, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17a, Lr30, LrB, Lr10, Lr14a, Lr18, Lr21, Lr28, and winter wheat lines with genes Lr41 and Lr42. In the United States in 2005, 72 virulence phenotypes of P. triticina were found. Virulence phenotype TDBGH, selected by virulence to resistance gene Lr24, was the most common phenotype in the United States, and was found throughout the Great Plains region. Virulence phenotype MCDSB with virulence to Lr17a and Lr26 was the second most common phenotype and was found widely in the wheat growing regions of the United States. Virulence phenotype MFPSC, which has virulence to Lr17a, Lr24, and Lr26, was the third most common phenotype, and was found in the Ohio Valley region, the Great Plains, and California. The highly diverse population of P. triticina in the United States will continue to present a challenge for the development of wheat cultivars with effective durable resistance to leaf rust.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2004

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, southeast, California, and Pacific Northwest, in order to determine the virulence of the wheat leaf rust population in 2004. Single uredinial isolates (757 in total) were derived from the collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3a, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17a, Lr30, LrB, Lr10, Lr14a, Lr18, Lr21, and Lr28, and winter wheat lines with genes Lr41 and Lr42. In the United States in 2004, 52 virulence phenotypes of P. triticina were found. Virulence phenotype MCDSB, selected by virulence to resistance genes Lr17a and Lr26, was the most common phenotype in the United States and was found in all wheat growing areas. Virulence phenotype TBBGG, with virulence to Lr2a, was the second most common phenotype and was found primarily in the spring wheat region of the north-central states. Virulence phenotype MBDSB, which has virulence to Lr17a, was the third most common phenotype and was found in all wheat growing areas except California. Phenotype TNRJJ, with virulence to genes Lr9, Lr24, and Lr41, was the fourth most common phenotype and occurred in the southeastern states and throughout the Great Plains region. Virulence phenotypes avirulent to a second gene in the Thatcher differential line with Lr1 increased in frequency in the United States in 2004. The highly diverse population of P. triticina in the United States will continue to present a challenge for the development of wheat cultivars with effective durable resistance.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2003

Collections of Puccinia triticina were obtained from rust infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Southeast, California, and the Pacific Northwest, in order to determine the virulence of the wheat leaf rust fungus in 2003. Single uredinial isolates (580 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. In the United States in 2003, 52 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which has been selected by virulence to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, the Ohio Valley, and California. Virulence phenotype THBJ, which has been selected by virulence to genes Lr16 and Lr26, was the second most common phenotype, and was found in the southern and northern central Great Plains region. Phenotype MCDS, which has been selected by virulence to genes Lr17 and Lr26, was the third most common phenotype and occurred in the same regions as MBDS. The use of wheat cultivars with leaf rust seedling resistance genes has selected leaf rust phenotypes with virulence to genes Lr9, Lr16, Lr17, Lr24, and Lr26. The population of P. triticina in the United States is highly diverse for virulence phenotypes, which will continue to present a challenge for the development of wheat cultivars with effective durable resistance.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2002

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Southeast, California, and the Pacific Northwest, in order to determine the virulence of the wheat leaf rust fungus in 2002. Single uredinial isolates (785 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. In the United States in 2002, 52 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which is virulent to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, and the Ohio Valley regions, and also in California. Phenotype MCDS, virulent to Lr17 and Lr26, was the second most common phenotype and occurred in the same regions as MBDS. Virulence phenotype THBJ, which is virulent to Lr16 and Lr26, was the third most common phenotype, and was found in the southern and northern central Great Plains region. Phenotype TLGJ, with virulence to Lr2a, Lr9, and Lr11, was the fourth most common phenotype and was found primarily in the Southeast and Ohio Valley regions. The Southeast and Ohio Valley regions differed from the Great Plains regions for predominant virulence phenotypes, which indicate that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains were similar for frequencies of predominant phenotypes, indicating a strong south to north migration of urediniospores.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2001

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Gulf Coast, California, Pacific Northwest, and Atlantic Coast States in order to determine the virulence of the wheat leaf rust fungus in 2001. Single uredinial isolates (477 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. The isolates also were tested for virulence on adult plants with leaf rust resistance genes Lr12, Lr13, Lr22a, Lr22b, Lr34, Lr35, and Lr37. In the United States in 2001, 44 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which is virulent to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, and Ohio Valley regions. Virulence phenotype THBJ, which is virulent to Lr16 and Lr26, was the second most common phenotype, and occurred almost exclusively in the north-central Great Plains region. Phenotype MCDS, which is virulent to Lr17 and Lr26, was the third most common phenotype and was found primarily in the Southeast, Ohio Valley, and Great Plains regions. The Southeast and Ohio Valley regions differed from the Great Plains region for predominant virulence phenotypes, which indicate that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains region differed for phenotypes with virulence to Lr16; however, the two areas had other phenotypes in common. Virulence to the adult plant resistance genes Lr35 and Lr37 was detected for the first time in North America in the MBDS, MCJS, and MCDS phenotypes.

Profile and activity of the bacterial biota of ground beef held from freshness to spoilage at 5-7 degrees C

Four samples of fresh ground beef were stored aerobically and held at 5-7 degrees C for up to 28 days. Although one sample initially yielded 21 different genera of bacteria while two others yielded only seven, all four spoiled essentially in the same way as assessed by aerobic, psychrotrophic, and Gram-negative counts, and by extract-release volume (ERV) and pH values. Pseudomonas spp. was dominant in the spoilage of all samples. As to why this group is so consistently associated with the low-temperature aerobic spoilage of fresh meats, it is hypothesized that they possess the capacity to form a biofilm and that quorum sensing is involved in the overall biofilm forming and functioning processes.

Effect of chronic intermittent immobilization stress on Fos-like immunoreactivity in rat brain and adrenal medulla

The present study examined the influence of short- and long-term chronic intermittent immobilization stress throughout the brain and on the adrenal medulla of intact rats using Fos-like immunoreactivity (Fos-LI) as a marker of cellular activation. The effect of adreno-medullectomy on the central nervous system (CNS) response to chronic immobilization stress was also examined. It was found that control unoperated, unstressed rats had no Fos-LI cells in the brain or in the adrenal medulla. In intact rats, neither short term (1 week) nor long term (4 weeks) chronic intermittent immobilization stress produced significant increases in Fos-LI in the CNS compared with control animals. However, marked increase in the number of Fos-LI cells was observed in the adrenal medulla of animals stressed for 4 weeks compared with control, unstressed animals or those stressed for 1 or 2 weeks. In adreno-medullectomised rats, 4 weeks, but not 1 week, chronic immobilization stress produced significant increases in numbers of Fos-LI neurons in the paraventricular hypothalamic and supraoptic nuclei and the medial amygdala compared with intact animals stressed for a similar period of time. It is concluded that long term stress produces chronic Fos-LI in the adrenal medulla and that adreno-medullectomy increases the Fos response of the PVN, supraoptic nucleus and medial amygdala to long term stress.

Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2000

Collections of Puccinia triticina were obtained from rust infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Gulf Coast, and Atlantic Coast States in order to determine the virulence of the wheat leaf rust fungus in 2000. Single uredinial isolates (1,120 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on 16 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes. In the United States in 2000, 54 virulence phenotypes of P. triticina were found. Virulence phenotypes MBDS and MCDS, which are virulent to resistance gene Lr17, were the first and third most common phenotypes in the United States and were found in the Great Plains and the Ohio Valley regions. MCRK, which is virulent to Lr26, was the second most common phenotype and was found primarily in the Southeast, Ohio Valley, and Northeast regions. In the northern area of the Great Plains, phenotypes with virulence to Lr16 increased in frequency from 1998 and 1999. The Southeast and Great Plains regions had different predominant virulence phenotypes, which indicates that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains region had the same predominant virulence phenotypes, indicating movement of virulence phenotypes of P. triticina within this region.

Virulence of Puccinia triticina on Wheat in the United States in 1999

Isolates of Puccinia triticina were obtained from wheat leaf collections made by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, and Gulf Coast states in 1999. Pathogenic races were determined from virulence/avirulence phenotypes on 14 host lines that are near-isogenic for leaf rust resistance. We found 58 races among 1,180 isolates in 1999. As in previous surveys, regional race distribution patterns showed that the central United States is a single epidemiological unit distinct from the eastern United States. The distinctive racial composition of collections from the Southeast, Northeast, and Ohio Valley indicates that populations of P. triticina in those areas are not closely connected, suggesting epidemics originate from localized overwintering sources.