Pembrolizumab in combination with gemcitabine for patients with HER2-negative advanced breast cancer: GEICAM/2015-04 (PANGEA-Breast) study

BACKGROUND

We evaluated a new chemoimmunotherapy combination based on the anti-PD1 monoclonal antibody pembrolizumab and the pyrimidine antimetabolite gemcitabine in HER2- advanced breast cancer (ABC) patients previously treated in the advanced setting, in order to explore a potential synergism that could eventually obtain long term benefit in these patients.

METHODS

HER2-negative ABC patients received 21-day cycles of pembrolizumab 200 mg (day 1) and gemcitabine (days 1 and 8). A run-in-phase (6 + 6 design) was planned with two dose levels (DL) of gemcitabine (1,250 mg/m² [DL0]; 1,000 mg/m² [DL1]) to determine the recommended phase II dose (RP2D). The primary objective was objective response rate (ORR). Tumor infiltrating lymphocytes (TILs) density and PD-L1 expression in tumors and myeloid-derived suppressor cells (MDSCs) levels in peripheral blood were analyzed.

RESULTS

Fourteen patients were treated with DL0, resulting in RP2D. Thirty-six patients were evaluated during the first stage of Simon's design. Recruitment was stopped as statistical assumptions were not met. The median age was 52; 21 (58%) patients had triple-negative disease, 28 (78%) visceral involvement, and 27 (75%) ≥ 2 metastatic locations. Progression disease was observed in 29 patients. ORR was 15% (95% CI, 5-32). Eight patients were treated ≥ 6 months before progression. Fourteen patients reported grade ≥ 3 treatment-related adverse events. Due to the small sample size, we did not find any clear association between immune tumor biomarkers and treatment efficacy that could identify a subgroup with higher probability of response or better survival. However, patients that experienced a clinical benefit showed decreased MDSCs levels in peripheral blood along the treatment.

CONCLUSION

Pembrolizumab 200 mg and gemcitabine 1,250 mg/m² were considered as RP2D. The objective of ORR was not met; however, 22% patients were on treatment for ≥ 6 months. ABC patients that could benefit of chemoimmunotherapy strategies must be carefully selected by robust and validated biomarkers. In our heavily pretreated population, TILs, PD-L1 expression and MDSCs levels could not identify a subgroup of patients for whom the combination of gemcitabine and pembrolizumab would induce long term benefit.

TRIAL REGISTRATION

ClinicalTrials.gov and EudraCT (NCT03025880 and 2016-001,779-54, respectively). Registration dates: 20/01/2017 and 18/11/2016, respectively.

Clinical profile of patients treated with evolocumab in lipid/internal medicine units of Spain. Observational study (RETOSS-IMU)

OBJECTIVE

To describe the clinical characteristics, the reasons for initiating therapy, and the effects of treatment in the initial phase of evolocumab availability in lipid/internal medicine units in Spain.

METHODS

Retrospective, observational study, based on the medical records of consecutive patients initiating treatment with evolocumab (from February 2016 to July 2017) in 20 internal medicine units in Spain. A review was made of the demographic and clinical characteristics of the patients, the lipid lowering treatment, and the evolution of the lipid profiles between 12weeks pre-initiation and 12±4weeks post-initiation of evolocumab.

RESULTS

A total of 136 patients were analysed, of whom 64.0% were men, and the mean age (standard deviation, SD) was 56.6 (11.5) years. The large majority (75%) had familial hypercholesterolaemia (4 homozygous), and 51.0% of them had suffered at least one cardiovascular event. Atherosclerotic cardiovascular disease (ASCVD) was present in 61% of all patients. At initiation of evolocumab, 61.0% of the patients were taking high-intensity statins, and 60.3% were receiving ezetimibe. The mean (and SD) of LDL-C levels at initiation of evolocumab was 169.1 (56.6) mg/dL. The LDL-C was greater than 160mg/dL in 46.4% of patients, and ≥190mg/dL in 26.5%. During the observation period, evolocumab produced significant reductions in LDL-C of 55.7% (P<.0001), achieving mean values of 74.3mg/dL. At week12, more than half (53.8%) of patients achieved LDL-C levels <70mg/dL, and 26.9% <50mg/dL.

CONCLUSIONS

In the lipid/internal medicine units, evolocumab was mainly prescribed in patients with familial hypercholesterolaemia, with or without ASCVD. The initial use of evolocumab was in accordance with the guidelines of the Spanish Society of Arteriosclerosis (SEA) of 2016, with LDL-C levels being well above the recommended thresholds for treatment initiation. Evolocumab treatment in clinical practice reduced LDL-C levels by about 55%, a similar reduction to that reported in clinical trials. Most patients achieved LDL-C goals.

SEOM clinical guidelines in hereditary breast and ovarian cancer (2019)

Mutations in BRCA1 and BRCA2 high penetrance genes account for most hereditary breast and ovarian cancer, although other new high-moderate penetrance genes included in multigene panels have increased the genetic diagnosis of hereditary breast and ovarian cancer families by 50%. Multigene cancer panels provide new challenges related to increased frequency of variants of uncertain significance, new gene-specific cancer risk assessments, and clinical recommendations for carriers of mutations of new genes. Although clinical criteria for genetic testing continue to be largely based on personal and family history with around a 10% detection rate, broader criteria are being applied with a lower threshold for detecting mutations when there are therapeutic implications for patients with breast or ovarian cancer. In this regard, new models of genetic counselling and testing are being implemented following the registration of PARP inhibitors for individuals who display BRCA mutations. Massive sequencing techniques in tumor tissue is also driving a paradigm shift in genetic testing and potential identification of germline mutations. In this paper, we review the current clinical criteria for genetic testing, as well as surveillance recommendations in healthy carriers, risk reduction surgical options, and new treatment strategies in breast cancer gene-mutated carriers.

SEOM clinical guidelines in early stage breast cancer (2018)

Breast cancer is the most common cancer in women in our country and it is usually diagnosed in the early and potentially curable stages. Nevertheless, around 20-30% of patients will relapse despite appropriate locoregional and systemic therapies. A better knowledge of this disease is improving our ability to select the most appropriate therapy for each patient with a recent diagnosis of an early stage breast cancer, minimizing unnecessary toxicities and improving long-term efficacy.

Abstract P4-21-05: Neoadjuvant non-pegylated liposomal doxorubicin plus paclitaxel, trastuzumab and pertuzumab in patients with HER2+ breast cancer – Final results of the SOLTI OPTI-HER HEART study

INTRODUCTION

Targeting HER2 by dual blockade with trastuzumab (T) and pertuzumab (P) in a taxane-based regimen is an active neoadjuvant treatment (NAT) of HER2+ early breast cancer (EBC). Addition of an anthracycline could further enhance this response, but potential cardiac toxicity is a concern. The Opti-HER HEART trial (NCT01669239) aims to optimize neoadjuvant treatment while minimizing cardiac risk, by combining T+P with a taxane and non-pegylated liposomal doxorubicin (NPLD).

MATERIAL AND METHODS

Phase II open-label, single-arm study of six 21-day cycles of NPLD (50mg/m2 D1), paclitaxel (80mg/m2 D1,8,15), T (4mg/kg C1D1, followed by 2mg/kg weekly), and P (840mg C1D1, followed by 420mg C2-6D1) as NAT for patients (pts) with stage II-IIIB HER2+ BC. Primary objective was to evaluate cardiac safety of the combination, measured by the incidence of type A (symptomatic congestive heart failure ) or type B [asymptomatic reduction of Left Ventricular Ejection Fraction (LVEF) value: ≥10% absolute decrease and LVEF&lt;50%, LVEF&lt;40% or any absolute decrease ≥20%] events, during NAT. Eighty-three pts were required to reject with 80% confidence the null hypothesis that the combination increases the incidence of cardiac events above the historical control of 18% (3% type A; 15% type B).

RESULTS

Between June 2013 and January 2015, 83 pts with HER2+ EBC (stage II 78%, stage III 22%) and adequate cardiac function (LVEF≥55%) were enrolled. Mean age was 50 years, N+ 47%, hormone receptor (HR) positive 71% and median baseline LVEF 66%. Eighty-five percent of pts completed 6 cycles of NAT, whereas 15% discontinued NAT due to toxicity. Adverse events (AEs) leading to dose adjustments/temporary interruptions and discontinuation of at least 1 drug occurred in 70% and 21% of pts, respectively. Primary objective was met with an incidence of cardiac events during NAT of 4% (95%CI 1-10, 3pts, all type B). Cardiac events until study completion (1 year) were 8% (all type B). All (but 2 cases with no follow-up data) were reversible and only 1 pt presented an asymptomatic LVEF&lt;40%. Neutropenia (45%) was the most frequent hematological toxicity (G3/4 34%; febrile neutropenia 6%), less frequent in the 71% of pts that received primary G-CSF prophylaxis (G3/4 25% vs. 67%). Common non-hematological toxicities were diarrhea (74%; G3 7%), asthenia (78%; G3 11%) and neurotoxicity (52%; G3/4 10%). Pathological complete response (pCR) in breast+axilla (ypT0/is ypN0) was 60% (87% in HR-) and 69% in breast (91% in HR-).

 TOTALHR-HR+% ypT0/is (95% CI)69 (58-79)91 (72-99)61 (47-74)% ypT0/is ypN0 (95% CI)60 (46-71)87 (66-97)50 (36-64)

CONCLUSIONS

The neoadjuvant combination of T+P, paclitaxel and NPLD does not increase the risk for cardiac events in HER2+ BC pts. Since cardiac toxicities may present later, long-term cardiac monitoring is essential. Efficacy in terms of pCR was remarkable, being higher to historical values of combinations with dual anti-HER2 blockade and one of the highest reported among HR-HER2+ BC. This regimen administered with primary G-CSF prophylaxis and cardiac function monitoring may be an effective and secure option for early and locally advanced HER2+ pts with good cardiac function.

Citation Format: Gavilá J, Perez-Garcia J, Calvo I, Ciruelos E, Muñoz M, Virizuela JA, Ruiz I, Andrés R, Morales S, Perelló A, Sánchez P, Garcia-Saenz JA, Quero Guillen JC, González-Santiago S, Garau Llinas I, González-Martín A, Cantos Sánchez de Ibargüen B, Zaragoza K, de la Peña L, Llombart-Cussac A, Oliveira M. Neoadjuvant non-pegylated liposomal doxorubicin plus paclitaxel, trastuzumab and pertuzumab in patients with HER2+ breast cancer – Final results of the SOLTI OPTI-HER HEART study [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 P4-21-05.

Preventive treatments for breast cancer: recent developments

Breast cancer is a burden for western societies, and an increasing one in emerging economies, because of its high incidence and enormous psychological, social, sanitary and economic costs. However, breast cancer is a preventable disease in a significant proportion. Recent developments in the armamentarium of effective drugs for breast cancer prevention (namely exemestane and anastrozole), the new recommendation from the National Institute for Health and Care Excellence to use preventative drugs in women at high risk as well as updated Guidelines from the US Preventive Services Task Force and the American Society of Clinical Oncology should give renewed momentum to the pharmacological prevention of breast cancer. In this article we review recent major developments in the field and examine their ongoing repercussion for breast cancer prevention. As a practical example, the potential impact of preventive measures in Spain is evaluated and a course of practical actions is delineated.

Prevalence of causes of secondary osteoporosis and contribution to lower bone mineral density in HIV-infected patients

SUMMARY

Eighty-one percent of human immunodeficiency virus (HIV)-infected patients had one or more of seven evaluated causes of secondary osteoporosis, and this rate increases with age. The type and number of causes were associated with a lower bone mineral density (BMD), and with an increased rate of osteopenia/osteoporosis, regardless of age and body mass index.

INTRODUCTION

The objective of this study was to determine whether factors of secondary osteoporosis were associated with lower BMD in HIV.

METHODS

This was a cross-sectional study of 285 HIV-infected patients (25 % females) evaluating the impact of seven different factors of reduced BMD: hyperthyroidism, diabetes, chronic viral hepatitis, chronic kidney disease (CKD), hypovitaminosis D, secondary hyperparathyroidism, and hypogonadism. Dual-energy X-ray absorptiometry scan of the femoral neck was obtained at the clinical visit.

RESULTS

Mean age was 45.7 years; osteopenia and osteoporosis were diagnosed in 38 and 6 %, respectively. Overall, 230 patients (81 %) had secondary factors; 107 (38 %) had only 1 cause, 94 (33 %) had 2, and 28 (10 %) had 3 or more, predominantly vitamin D deficiency in 61 %, hepatitis C virus coinfection in 45 %, and secondary hyperparathyroidism in 27 %. The number of secondary factors was closely related to a lower BMD, which is statistically significant for patients having ≥2 causes (0.77 vs 0.73 g/cm(2), p = 0.02). The rate of osteopenia ranged from 36 % without any cause to 57 % with three or more, osteoporosis from 0 to 19 %, and Z-score <-2 SD from 0 to 27 %, respectively. In a multivariate linear regression, adjusting by age, body mass index, and HIV-related factors, the number of secondary factors was independently associated with a lower BMD (ß coefficient -0.134; p = 0.02), mainly due to patients with hepatitis C virus (HCV) coinfection, secondary hyperparathyroidism, and CKD.

CONCLUSIONS

A high prevalence of secondary causes of osteoporosis is observed in HIV-infected patients, and its type and cumulative number determine a lower BMD, after adjusting by age and body mass index.

Phase II trial of sequential subcutaneous interleukin-2 plus interferon alpha followed by sorafenib in renal cell carcinoma (RCC)

PURPOSE

Immunotherapy (IL-2 and INF-α) was the treatment of choice for advanced renal cell carcinoma (RCC) until antiangiogenic therapy with tyrosin kinase inhibitors was developed in the early 2000s. This clinical trial explored the efficacy and toxicity of sequential treatment of IL-2 plus INF-α followed by sorafenib.

METHODS

Eligibility criteria included measurable, non-resectable, histologically confirmed predominantly clear cell RCC, no prior systemic treatment, and ECOG PS 0-2. The treatment regimen was a 6-week cycle of subcutaneous IL-2 at 9 × 10(6) IU on days 1-6 of weeks 1, 2, 4 and 5 plus s.c. INF-α at 6 × 10(6) IU on days 1, 3 and 5 of weeks 1-6. Responders received 6 additional weeks of this regimen. All patients received oral sorafenib (400 mg bid) after immunotherapy until disease progression. The primary endpoint was progression-free survival.

RESULTS

Forty-one patients were enrolled, median age 57 years. ECOG was 0/1 in 17/20 patients, 35 patients had prior nephrectomy and 18 patients pure clear cell cancer. Median PFS was 7.4 months (95 % CI 6.5-13.1) and OS was 16.6 months (95 % CI not reached). In 36 patients evaluable for response, ORR was 44.4 % and control rate was 94.4 %. Most adverse events (AEs) were Grade 1 or 2 toxicities (84.7 %). During immunotherapy the most common AEs were pyrexia (82.9 %), asthenia (56.1 %) and anorexia (46.3 %), whereas during sorafenib were diarrhoea (48.8 %) and hand-foot syndrome (46.3 %).

CONCLUSIONS

A sequential regimen of IL-2 and INF-α followed by sorafenib showed effectiveness and manageable toxicity in patients with advanced RCC.

Gemcitabine and capecitabine in previously anthracycline-treated metastatic breast cancer: a multicenter phase II study (SOLTI 0301 trial)

BACKGROUND

On the basis of clinical activity of capecitabine and gemcitabine for metastatic breast cancer, we carried out a multicenter phase II clinical trial on the combination of these two agents in advanced anthracycline-pretreated breast cancer patients. Main objectives were to assess its efficacy and safety profile.

PATIENTS AND METHODS

Seventy-six anthracycline-pretreated breast cancer patients were evaluated and were stratified according to previous treatment of advanced disease (group-1: not previously treated and group-2: previously treated). Study treatment consisted of gemcitabine 1000 mg/m(2), i.v., as 30 min-infusion, days 1 and 8 every 21 days, plus oral capecitabine 830 mg/m(2) b.i.d., days 1-14 every 21 days.

RESULTS

Overall response rate was 61% for group-1, 48.5% for group-2 and 55.2% for the whole population. Clinical benefit rate was 73% for group-1, 80% for patients in group-2 and 76% for all patients. Median time to progression was 13.0 months for group-1, 8.2 months for group-2 and 11.1 months for the whole population. Most frequent grade 3-4 observed toxic effects per patient were neutropenia (60%), asymptomatic liver toxicity (13.5%), asthenia (14%) and hand-foot syndrome (16%). Only one patient presented febrile neutropenia. No treatment-related deaths occurred.

CONCLUSION

Combination of gemcitabine and capecitabine is an active and safe regimen in anthracycline-pretreated breast cancer patients.

Observational study in patients with pulmonary metastases of renal cell carcinoma receiving inhaled recombinant interleukin-2 (rIL-2)

4603

Background: Patients with metastatic renal cell carcinoma have a poor prognosis, including those with pulmonary metastases (PMRCC). The objective of this study was to obtain efficacy and safety data on inhaled rIL-2 used in clinical practice in PMRCC patients. Methods: Data provided from 107 PMRCC patients from 48 centres in Spain and 6 in Portugal, treated with inhaled rIL-2 between 2000 and 2005 were evaluated. Data were analyzed by ITT, considering a valuable patient when receiving the first dose of inhaled rIL-2. The treatment schedule was: 3 cycles of 36 MIU rIL-2 per day for 5 days/week for 12 weeks (with one week treatment free between cycles) in Spain and for 3 weeks (out of each 4 weeks) for 12 weeks in Portugal. Efficacy was assessed by best response following each treatment cycle and overall (WHO criteria). The Kaplan-Meier method was used to estimate progression free survival (PFS) and overall survival (OS) that were measured from the time of administration of the first dose of inhaled rIL-2 until progression or death. Safety data were analysed using descriptive statistics, with toxicities expressed as number of weeks in which each toxicity was reported by cycle and by grade. Results: After 1902 treatment weeks administered (median 17.8), the overall objective response rate (complete and partial response,) was 12.2% (95% CI: 6.0–18.4) and a stable disease rate of 22.45% (95% CI: 14.5–30.3). Median PFS and OS were 3.72 (95% CI: 2.86–4.57) and 18.5 (12.69– 23.61) months, respectively. Non-haematological toxicities were the most notable adverse events observed, especially in terms of cough (20.4% of weeks) and fatigue (4.4%) being grade 1 or 2 in severity and reversible by removing the treatment in all cases. Conclusions: This study provides data of efficacy and mild toxicity of inhaled rIL-2. On the basis of these findings inhaled rIL-2 might be considered as an alternative to its systemic administration to treat patients with PMRCC.

No significant financial relationships to disclose.

Multicenter phase II study of liposomal doxorubicin (M) and docetaxel (T) as neoadjuvant treatment in patients with stage II - III breast cancer

10662

Background: T and M is a very active chemotherapy regimen for breast cancer. M has been shown to be as effective as doxorubicin at same doses while reducing the cardiotoxicity and causing less myelosuppression. This study was designed to evaluate clinical and pathological response rate (RR) and toxicity after induction chemotherapy in patient with breast cancer. Methods: Patients with histological confirmation of breast cancer (stage II-III and inflammatory), age > 18 years, left ventricular eject fraction > 45% and adequate bone marrow, renal and hepatic function were included in the study. Prior systemic therapy or radiotherapy and surgery for breast cancer were not allowed. Treatment: T (75 mg/m2) iv and M (75 mg/m2) iv, every 21 days during 4 cycles, followed by surgery. Results: To date 59 patients have been enrolled; 50 were included in this interim analysis, with a median age of 52 years old (28–76), ECOG PS 0, 88.0%; ECOG PS 1, 12.0%; breast location: right, 52.0%; peri-postmenopausal status, 44.9%. Positive hormonal receptor status was 63.3%. Histology was ductal carcinoma in 84.0%. Patients received a total of 188 cycles (median 4, range 2–4). Median relative dose intensity was 99% for T and for M. Efficacy: Nine patients were non-evaluable (7 on treatment, 1 consent withdrawal and 1 lost of follow-up). Of 41 evaluable patients, 5 achieved complete response (CR) (12.2%), 26 partial response (PR)(63.4%), 9 stable disease (SD) (22.0%) and 1 progressive disease (PD) (2.4%), resulting in a clinical response rate (RR) of 75.6% (95% CI: 62.5–88.7%). Surgery was performed in 40 patients: six (15.0%) of them had pathological (p) CR, 25 (62.5%) pPR, 9 (22.5%) pSD resulting in a pathological RR of 77.5% (95% CI: 64.6–90.4%). Median of time to progression and overall survival has not been achieved yet. Hematological toxicities grades III/IV per patient were neutropenia (14%), thrombocytopenia (4%), leukopenia (2%), anemia (2%) and febrile neutropenia (12%). Non-hematological grade III/IV toxicities per patient were asthenia (6%), nausea / vomiting (4%) and infection (4%). Conclusions: T and M every 21 days during 4 cycles as induction chemotherapy in stage II and III breast cancer is an active and well tolerated treatment.

No significant financial relationships to disclose.

Axillary lymphadenectomy can be safely avoided in patients with breast cancer and negative sentinel lymph node biopsy

10787

Background: Patients with breast cancer in which sentinel lymph node biopsy is histologically negative for tumor cells, have a low probability of having involvement of additional regional lymph nodes. Lymph node dissection may be avoided in these cases. Methods: Ninety-six consecutive patients with invasive breast cancer and tumour size less than 2 centimeters by mammography, had lymphoscintigraphy with colloidal 99Tc and radioisotope-guided sentinel lymph node biopsy in the University Hospital of Zaragoza from 1999 to 2005.Pathological assessment included serial sections of the sentinel lymph node with immunohistochemistry for cytokeratins in selected cases. Results: Sentinel lymph node biopsy was negative in 57 patients. There were 56 females and 1 male. Median age was 57 years (range 24–87). Median pathological tumor size was 15 mm (range 5–31). Location of the sentinel lymph node was axillary in 47patients, internal mammary in 0 patients, and both in 10 patients. Median number of resected lymph nodes was 2 (range 1–4). With median follow-up of 33 months, no local or systemic relapses have occurred. Conclusions: Avoidance of regional lymph node dissection is safe in patients with breast cancer and histologically negative sentinel lymph node biopsy.

No significant financial relationships to disclose.

[Surveillance of commensal flora evolution and infections in neutropenic cancer patients submitted to chemoprophylaxis]

The evolution of the flora and its resistance to different antimicrobials in neutropenic patients submitted to high-dose chemotherapy with autologous blood stem-cell transplantation, and the relation of these findings to the etiology of the infections the patients developed was studied in order to evaluate the suitability of the chemoprophylaxis and the empirical antibiotic therapy used. Forty-one patients were analyzed in a period of 28 months. The chemoprophylaxis used was levofloxacin, fluconazole and acyclovir. The empirical sequential treatment was an initial administration of cefepime, followed by teicoplanin and amikacin. Cultures were done of nasal and pharyngeal smears, Hickman catheter and stools, 1 day before chemoprophylaxis started and then on days 5 and 9. In the case of fever, three sets of blood cultures and urine cultures were done and samples from areas related to the clinical condition were analyzed. Levofloxacin induced the selection of resistant strains or species in the flora and in the infectious agents. Fluconazole also selected resistant species in the flora. Seventeen infections were documented in eleven patients, produced by Gram-positive bacteria in thirteen cases (81.25%) and by Gram-negative bacteria in three (18.75%). The coagulase negative staphylococci and Enterococcus faecalis were the most frequent agents of infection. We identified on nine occasions the same microorganism in the flora and in the pathological product; this suggests its endogenous origin and supports the use of prospective cultures of the flora, monitoring the sensibility of the microorganisms isolated to the antimicrobials used in chemoprophylaxis and empirical treatment.

Rational design of three-dimensional (3D) optically active molecule-based magnets: synthesis, structure, optical and magnetic properties of ([Ru(bpy)3](2+), ClO4(-), [Mn(II) Cr(III)(ox)3](-))n and ([Ru(bpy)2ppy](+), [M(II)Cr(III)(ox)3](-))n, with M(II) = Mn(II), Ni(II). X-ray structure of ([deltaRu(bpy)3](2+), ClO4(-), [deltaMn(II)DeltaCr(III)(ox)3](-))n and ([lambdaRu(bpy)2ppy)](+), [lambdaMn(II)lambdaCr(III)(ox)3](-))n

To elucidate the relation between structural and magnetic properties, we have synthesized molecular materials having both Cotton effects and a ferromagnetic long range order. Such optically active 3D molecule-based magnets were rationally designed using the enantioselective template effect of optically active cations, namely Delta or Lambda [Ru(bpy)3, ClO4](+) or Delta or Lambda [Ru(bpy)3ppy](+) (bpy = bipyridine; ppy = phenylpyridine). Such cations are able to template the formation of optically active 3D anionic networks in which transition metal ions (Cr-Mn) and (Cr-Ni) are connected by oxalate ligands (ox). Following this strategy, we described the synthesis of ([Ru(bpy)3](2+), ClO4(-), [Mn(II)Cr(III)(ox)3](-))n and ([Ru(bpy)2ppy](+), [M(II)Cr(III)(ox)3](-))n with M(II) = Mn(II), Ni(II) in their optically active forms. In these 3D networks, all of the metallic centers have the same configuration, Delta or Lambda, as the template cation. We have determined the structure of ([DeltaRu(bpy)3][ClO4][DeltaMnDeltaCr(ox)3])n and ([LambdaRu(bpy)2ppy](+), [LambdaMn(II)LambdaCr(III)(ox)3](-))n by X-ray diffraction studies. These optically active networks show the Cotton effect and long-range ferromagnetic order at low temperatures. The magnetic circular dichroism of ([Ru(bpy)3](2+), ClO4(-), [Mn(II)Cr(III)(ox)3](-))n at 2 K is reported.

Cobalt-complexed conjugated diyne salts: a family of rigid masked dielectrophiles. Syntheses, structures, and double nucleophilic substitutions

A family of dicationic diyne salts of the general formula [(Co2(CO)6)2-mu,eta2,eta2-(Nu-CH2C(triple bond)C-C(triple bond)CCH2-Nu)][BF4]2 [Nu = SMe2 (3); Nu = NC6H7, 3-picoline, (5); Nu = NC9H7, quinoline (7)] were prepared and fully characterized. Three X-ray molecular structures of 3, 5, and the neutral starting material 2,4-hexadiyne-1,6-diol complex [(Co2(CO)6)2-mu,eta2,eta2-(HO-CH2C(triple bond)C-C(triple bond)CCH2-OH)] (1) are presented. Complex 1 crystallizes in the triclinic space group P1 with a = 14.722(2) A, b = 14.571(3) A, c = 14.722(2) A, alpha = 105.17(1) degrees, beta = 113.30(1) degrees, gamma = 99.20(1) degrees, and Z = 4. Complex 3 crystallizes in the monoclinic space group P2(1)/n with a = 12.758(3) A, b = 13.360(3) A, c = 20.494(3) A, beta = 91.44(1) degrees, and Z = 4, and compound 5 also crystallizes in the monoclinic space group P2(1)/n with a = 9.426(2) A, b = 21.739(5) A, c = 18.704(3) A, beta = 94.86(1) degrees, and Z = 4. The X-ray structures provide us with valuable information on the arrangement of the Co2-alkyne units, which have a cis geometry and are in sharp contrast to that observed generally for diyne-tetracobalt compounds. Complex [(Co2(CO)6)2-mu,eta2,eta2-(Me2S-CH2C(triple bond)C-C(triple bond)CCH2-SMe2)][BF4]2 (3) reacts with N-, S-, and P-centered nucleophiles and affords the related substituted complexes in high yields. The stability and reactivity of the disulfonium diyne complex 3 toward nucleophiles are compared to those of the analogous disulfonium-yne complex [(Co2(CO)6)2-mu,eta2,eta2-(Me2S-CH2-C(triple bond)C-CH2-SMe2)][BF4]2 (4).

Direct evidence of acute stress-induced facilitation of ACTH response to subsequent stress in rats

To determine the role of glucocorticoids in the appearance of the facilitatory effect of stress on the ACTH response to a subsequent stress, sham-operated (Sham) rats and rats adrenalectomized (ADX) and supplemented with 50 mg/l corticosterone (B) in the drinking saline (ADX + B) were subjected to 1 min of immobilization stress (Imo) four consecutive times with an interstressor interval of 90 min. Sham rats showed a similar pattern of ACTH response to the first and fourth exposures to Imo. ADX + B rats showed an exacerbated ACTH response to the fourth Imo, despite higher prestress levels than those observed before the first Imo. In another experiment, no facilitatory effect of previous stress on ACTH response was found in ADX rats, but supplementation with B in the drinking saline for 1 wk resulted in facilitation of the ACTH response. We conclude that repeated exposure to a short-time stress induces a facilitatory effect on the ACTH response that is uncovered by eliminating stress-induced glucocorticoid release but needs B doses resulting in approximately basal circulating glucocorticoid levels to be induced or expressed.

Defective ACTH response to stress in previously stressed rats: dependence on glucocorticoid status

The effect of previous exposure to stress on the pituitary-adrenal response to a further stress was characterized in rats with different glucocorticoid status: sham-operated rats (Sham), adrenalectomized (ADX) rats, and ADX rats supplemented with a low corticosterone (B) dose in the drinking saline (ADX + B). Previous exposure of Sham rats to 1 h of immobilization (Imo) reduced, 2 h later, the ACTH response to a second severe stressor (Imo) but not to a less severe stressor (tail shock). In ADX rats, previous Imo totally suppressed the ACTH response to Imo or to shock. In ADX + B rats the response to shock was blocked and that to Imo tended to be lower. These changes were not explained by depletion of adenohypophysial ACTH stores. After previous Imo, reduced response to corticotropin-releasing factor was observed in Sham and ADX + B, but not in ADX, rats. Taken together, the present results suggest that the reduced ACTH response of previously stressed rats to a second severe stress is observed in the presence and absence of glucocorticoids, but the main site at which such inhibition occurs might be critically dependent on the glucocorticoid status.

Activation of the hypothalamic-pituitary axis in adrenalectomised rats: potentiation by chronic stress

The influence of chronic stress on the status of the hypothalamo-pituitary-adrenal (HPA) axis of sham-operated and adrenalectomised rats was assessed. Animals underwent bilateral adrenalectomy (ADX) and 3 days later they were either left undisturbed or subjected daily to immobilization for 2 h each morning for 14 days (chronic IMO). In situ hybridization histochemistry revealed that ADX increased corticotropin-releasing factor (CRF) mRNA levels in the paraventricular nucleus of the hypothalamus (PVN) and proopiomelanocortin (POMC) mRNA levels in the anterior pituitary, in both control and chronically stressed rats as measured on the day following the last exposure to stress. Chronic IMO increased CRF mRNA levels in the PVN and POMC mRNA levels in the anterior pituitary of sham-operated rats, as measured on the day following the last exposure to stress. Chronic IMO potentiated the increase in CRF mRNA in the PVN following ADX and resulted in further increases in CRF mRNA above levels seen in adrenal-intact animals. Finally, chronic stress, while not altering basal ACTH levels of ADX rats, reduced the ACTH response of these animals to a novel stressor (tail-shock for 30 min). These results suggest that chronic stress exerts a stimulatory influence at the hypothalamic level that is partially restrained by daily stress-induced glucocorticoid release. Despite the potentiation by chronic stress of CRF mRNA content in the PVN of ADX rats, a blunted circulating ACTH response to an acute short-term stressor was apparent in ADX-chronically stressed rats, suggesting that chronic stress might also alter POMC processing and/or ACTH secretory patterns in the anterior pituitary in ADX animals.

Ganglioside and phospholipid composition of forebrain, cerebellum, and brain stem from adult and newborn rats

The aim of this study was to elucidate whether sex or pregnancy state might affect the content and/or pattern of gangliosides from the forebrain, cerebellum and brain stem of rats. Adult male, mother (1-day after offspring) and nonpregnant rats of similar age were analyzed. Non-significant differences in ganglioside concentrations and patterns were found for the respective neural area of adult male and female rats except for a decrease in cerebellum and brain stem content from mothers and 12.0 months-old males, respectively. Thus, it seems that neither sex nor pregnancy hormones affect these parameters. By contrast, significant differences were found for pattern and ganglioside contents between adult (male and female) rats and newborns (1 day-old). Newborns showed a significant decrease in their forebrain (2.5-fold), cerebellum (2.0-fold) and brain stem (2.0-fold) ganglioside content when compared with adult (male and female) rats. Significant increases (p less than 0.001) were found in the phospholipid and cholesterol contents in the different brain areas in mothers versus their newborns. The phospholipid pattern also showed significant changes in all brain areas, with an increase (p less than 0.001) in phosphatidylethanolamine percentage in adult animals, among the main variations. An explanation for these facts is suggested.