Search

Abstract Background Actinomycin-D (Act-D) and Methotrexate (MTX) are both effective first-line agents for low-risk gestational trophoblastic neoplasia (LRGTN) with no consensus regarding which is more effective or less toxic. The primary objective of this meta-analysis is to compare Act-D with MTX in the treatment of LRGTN. Methods We systematically searched electronic databases, conferences abstracts and trial registries for randomized controlled trials (RCTs) and high-quality non-randamized controlled trials (non-RCTs), comparing Act-D with MTX for patients with LRGTN. Studies were full-text screened for quality assessment and data extraction. Eligible studies must have reported complete remission rate. A fixed-effects meta-analysis was conducted to quantify the efficacy and safety of Act-D and MTX on odds ratios (ORs) and 95% confidence intervals (95%CIs), respectively. Results A total of 8 RCTs and 9 non-RCTs (1674 patients) were included. In terms of efficacy, Act-D is superior to MTX in complete remission (80.2% [551/687] vs 65.1% [643/987]; OR 2.15, 95%CI 1.70 to 2.73). In the stratified analysis, patients from RCTs and non-RCTs both had a better complete remission from Act-D-based regimen (RCTs: 81.2% [259/319] vs 66.1% [199/301], OR 2.17, 95%CI 1.49 to 3.16; non-RCTs: 79.3% [292/368] vs 65.0% [444/686], OR 2.14, 95%CI 1.57 to 2.92). In terms of safety, patients receiving Act-D had higher risks of suffering nausea (OR 2.35, 95%CI 1.68 to 3.27), vomiting (OR 2.40, 95%CI 1.63 to 3.54), and alopecia (OR 2.76, 95%CI 1.60 to 4.75). Notably, liver toxicity (OR 0.38, 95%CI 0.19 to 0.76) was the only one that was conformed to have a higher risk for patients receiving MTX. In addition, the pooled results showed no significant difference of anaemia, leucocytopenia, neutropenia, thrombocytopnia, constipation, diarrhea, anorexia, and fatigue between Act-D and MTX. Conclusions Our meta-analysis suggests that Act-D had better efficacy profile in general, and MTX had less toxicities in LRGTN. Future clinical trials should be better orchestrated to provide more valid data on efficacy and toxicity.

Background: Treatment of Ewing sarcoma (ES) requires multidisciplinary approach and deficiencies in treatment adversely affect the results. This study included patients diagnosed with ES and aimed to determine the factors affecting prognosis and investigate the efficacy of replacing actinomycin-D with carboplatin in consolidation treatment. Methods: Eighty-two pediatric ES patients diagnosed at a single institution between 2005 and 2020 were retrospectively evaluated. Clinical and epidemiological features, treatment modalities, prognostic criteria, and overall survival (OS) rates of patients revieved. In consolidation treatment, 22 patients were treated with actinomycin-D and 32 patients with carboplatin (500 mg/m2/dose), 24 patients could not receive consolidation treatment. The 5- and 10-year OS rates of the patients were compared. Results: The 5- and 10-year OS rates of the 82 patients with ES were 46% and 40%, respectively. The 5-year OS rates in the group with localized disease (n = 55) and metastasis (n = 27) at diagnosis were 54% and 26%, respectively (p = 0.006). When evaluated according to the consolidation treatment administered both the 5- and 10-year OS rates of the patients receiving actinomycin-D were 50%. The 5-year OS rate was 58% in the carboplatin group, and the 5- and 10-year OS rates of patients that did not receive consolidation treatment was 20%. Conclusions: Survival was significantly worse in the group that did not receive consolidation treatment. Furthermore, our results suggested that carboplatin could be used effectively as an alternative to actinomycin-D in ES consolidation treatment.

Copyright of Practical Pharmacy & Clinical Remedies is the property of Editorial Department of Practical Pharmacy & Clinical Remedies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Actinomycin-D (Act-D) and Methotrexate (MTX) are both effective first-line agents for low-risk gestational trophoblastic neoplasia (LRGTN) with no consensus regarding which is more effective or less toxic. The primary objective of this meta-analysis is to compare Act-D with MTX in the treatment of LRGTN.Methods: We systematically searched electronic databases, conferences abstracts and trial registries for randomized controlled trials (RCTs) and high-quality non-randamized controlled trials (non-RCTs), comparing Act-D with MTX for patients with LRGTN. Studies were full-text screened for quality assessment and data extraction. Eligible studies must have reported complete remission rate. A fixed-effects meta-analysis was conducted to quantify the efficacy and safety of Act-D and MTX on odds ratios (ORs) and 95% confidence intervals (95%CIs), respectively.Results: A total of 8 RCTs and 9 non-RCTs (1674 patients) were included. In terms of efficacy, Act-D is superior to MTX in complete remission (80.2% [551/687] vs 65.1% [643/987]; OR 2.15, 95%CI 1.70 to 2.73). In the stratified analysis, patients from RCTs and non-RCTs both had a better complete remission from Act-D-based regimen (RCTs: 81.2% [259/319] vs 66.1% [199/301], OR 2.17, 95%CI 1.49 to 3.16; non-RCTs: 79.3% [292/368] vs 65.0% [444/686], OR 2.14, 95%CI 1.57 to 2.92). In terms of safety, patients receiving Act-D had higher risks of suffering nausea (OR 2.35, 95%CI 1.68 to 3.27), vomiting (OR 2.40, 95%CI 1.63 to 3.54), and alopecia (OR 2.76, 95%CI 1.60 to 4.75). Notably, liver toxicity (OR 0.38, 95%CI 0.19 to 0.76) was the only one that was conformed to have a higher risk for patients receiving MTX. In addition, the pooled results showed no significant difference of anaemia, leucocytopenia, neutropenia, thrombocytopnia, constipation, diarrhea, anorexia, and fatigue between Act-D and MTX.Conclusions: Our meta-analysis suggests that Act-D had better efficacy profile in general, and MTX had less toxicities in LRGTN. Future clinical trials should be better orchestrated to provide more valid data on efficacy and toxicity. [ABSTRACT FROM AUTHOR]

Actinomycin-D and vincristine are cytotoxic drugs commonly used to treat cancers in children. This prospective study assessed pharmacokinetic variability and toxicity of these drugs in children. Blood samples were collected in 158 patients. Actinomycin-D or vincristine concentrations were quantified using high-performance liquid chromatography–tandem mass spectrometry. Pharmacokinetic parameters were estimated using non-compartmental methods. Target toxicities were collected prospectively. Actinomycin-D pharmacokinetics (n = 52 patients) were highly variable. The median (coefficient of variation, CV%) area under the concentration–time curve (AUC) was 332 ng/mL·h. (110%); clearance was 4.6 L/h/m2 (90%); half-life was 25 h (60%). No patient met the defined criteria for myelosuppression. In multivariate analysis, none of the demographic nor pharmacokinetic parameters was predictors of acute hepatotoxicity. Vincristine pharmacokinetics (n = 132 patients) demonstrated substantial variability. The median (CV%) AUC was 78 ng/mL·h (98%); clearance was 17.2 L/h/m2 (67%); half-life was 14.6 h (73%). In multivariate analysis, the effect of increasing age for a given BSA was an increase in neuropathy while the effect of increasing BSA for a given age was a decrease in neuropathy. Conclusion: Pharmacokinetics of both drugs were highly variable. For actinomycin-D, there was no correlation between demographic or pharmacokinetic parameters and target toxicities. For vincristine, the correlations of age and BSA and neuropathy are confounded by the correlation between age and BSA in children and the ability to ascertain neuropathy in infants. Variability may be attributed to dose reductions and capped doses for both drugs. Investigation of BSA-based dosing in young children is warranted to decrease variability of exposure. [ABSTRACT FROM AUTHOR]

Methotrexate and actinomycin-D are both effective first-line drugs for low-risk (WHO score 0–6) Gestational Trophoblastic Neoplasia (GTN) with considerable debate about which is more effective, less toxic, and better tolerated. The primary trial objective was to test if treatment with multi-day methotrexate (MTX) was inferior to pulse actinomycin-D (ACT-D). Secondary objectives included evaluation of severity and frequency of adverse events, and impact on quality of life (QOL). This was a prospective international cooperative group randomized phase III two arm non-inferiority study (Clinical Trials Identifier: (NCT01535053). The control arm was ACT-D; the experimental arm was multi-day MTX regimen (institutional preference of 5 or 8 day). Outcome measures included complete response rate, recurrence rate, toxicity, and QOL as measured by FACT-G and FACIT supplemental items. The complete response rates for multi-day methotrexate and pulse actinomycin-D were 88% (23/26 patients) and 79% (22/28 patients) (p = NS) respectively, there were two recurrences in each arm, and 100% of patients survived. Significant toxicity was minimal, but mouth sores (mucositis), and eye pain were significantly more common in the MTX arm (p = 0.001 and 0.01 respectively). Quality of life showed no significant difference in overall quality of life, body image, sexual function, or treatment related side effects. The study was closed for low accrual rate (target 384, actual accrual 57), precluding statistical analysis of the primary objective. The complete response rate for multi-day methotrexate was higher than actinomycin-D, but did not reach statistical significance. The multi-day MTX regimens were associated with significantly more mucositis and were significantly less convenient. • Multi-day methotrexate had an 88% complete response rate in low risk GTN. • Every two week actinomycin-D had a 79% complete response rate in low risk GTN. • The survival rate for patients in this study was 100% • Quality of life showed no significant difference in overall quality of life, body image, or sexual function. • The MTX arm reported more treatment concerns and disruption of lifestyle, but this was not significant. [ABSTRACT FROM AUTHOR]

Low-risk non-metastatic gestational trophoblastic neoplasia (GTN) has been treated with single agent chemotherapy, but second curettage is emerging as an alternative strategy with reported cure rates of 40%. We sought to estimate the cost-effectiveness of second curettage as the first line treatment of low-risk GTN. A decision-analytic model was created using TreeAge software to compare costs and outcomes for women with WHO staged low-risk GTN undergoing treatment with 5-day methotrexate (MTX), biweekly pulsed actinomycin-D, or second curettage. Probabilities were derived from the literature. Outcomes of interest included side effects from chemotherapy, need for additional agents, hemorrhage, uterine perforation, and cure rates. Utilities were applied to discounted life expectancy at a rate of 3% to generate quality adjusted life years (QALYs). Sensitivity analyses were then performed in order to assess the robustness of our assumptions. Of the three treatment arms, MTX was associated with the lowest cost and had similar QALYs to the other studied modalities. Second curettage was associated with 49 additional cures when applied to a theoretic cohort of 1000 women, as well as an additional 83 hemorrhages and 17 uterine perforations. Sensitivity analysis on the cure rate of second curettage revealed that second curettage was not cost-effective over MTX unless its probability of cure was 98%. Our study found 5-day MTX was the cost-effective strategy for treatment of women with low-risk, non-metastatic GTN when compared to second curettage and actinomycin-D. In a carefully selected patient population, second curettage may be an additional treatment strategy. • 5-day MTX is the most cost-effective treatment of low-risk, non-metastatic GTN. • MTX is more cost-effective than second curettage unless the cure rate of second curettage is 98%. • Actinomycin-D is both more costly and associated with fewer quality-adjusted life years than either MTX or second curettage. [ABSTRACT FROM AUTHOR]

Isolated limb infusion (ILI) with cytotoxic agents is a simple and effective treatment option for patients with melanoma in-transit metastases (ITMs) confined to an extremity. Data for ILIs performed in Europe are sparse and to date no Eastern European ILI experience has been reported. The aim of the current study was to evaluate the efficacy of ILI in Estonia. Data for twenty-one patients were collected and analysed. All patients had melanoma ITMs and underwent an ILI between January 2012 and May 2018. The cytotoxic drug combination of melphalan and actinomycin-D was used. Drug circulation times were 20–30 min under mildly hyperthermic conditions (38–39 °C). Primary outcome measures were treatment response and overall survival. Nineteen lower limb and two upper limb ILIs were performed. The female to male ratio was 18:3. The overall response rate (complete + partial response) was 76% (n = 16), with a complete response in 38% (n = 8). The overall long-term limb salvage rate was 90% (n = 19). During follow-up, eight patients (38%) died, two due to metastatic melanoma. Five-year overall survival was 57%. This first Eastern European report of ILI for melanoma ITMs shows results comparable to those from other parts of the world. In this era of effective targeted and immune therapies, ILI remains a useful treatment option, with a high overall response rate and durable responses in patients with melanoma ITMs confined to a limb. [ABSTRACT FROM AUTHOR]

The DMAC protocol (dexamethasone, melphalan, actinomycin‐D, cytarabine) has been evaluated in American studies for the treatment of relapsed canine lymphoma, comparing similarly to other rescue protocols. The aim of this study was to evaluate efficacy and toxicity of DMAC, in a larger UK cohort of resistant canine lymphomas. Medical records of dogs with resistant non‐Hodgkin high‐grade lymphomas that received DMAC as a rescue protocol were reviewed from 2007 to 2017. Response, time from initiation to discontinuation (TTD) and toxicity (Veterinary Cooperative Oncology Group criteria) were assessed. One hundred dogs were included; 86 received CEOP (modified CHOP including epirubicin) as first‐line treatment. Thirty‐five dogs (35%) responded: 21 complete responders (CRs) and 14 partial responders (PRs). Responders had significantly longer TTD (P < 0.001) compared with non‐responders: 62 days (range 28‐952) for CR vs 32 days (range 20‐70) for PR. Six CR received more than six cycles of DMAC (range 7‐36 cycles) and experienced a longer TTD (median 508, range 126‐952 days). Thrombocytopenia occurred in 45% (24 grade 1‐2, 21 grade 3‐4) and neutropenia in 36% of cases (29 grade 1‐2, 7 grade 3‐4). Gastrointestinal toxicity occurred in 42% of dogs (40 grade 1‐2, 2 grade 3‐4). Owing to chemotherapy toxicity, treatment was discontinued in five, and hospitalization required in six cases. In this study, response to DMAC was lower and of generally shorter duration than previously reported. Toxicity was high, but infrequently led to hospitalization or discontinuation of treatment. [ABSTRACT FROM AUTHOR]

To evaluate the impact of periodic shortage of actinomycin- d (Act- d) in the treatment of Brazilian patients with low-risk gestational trophoblastic neoplasia (GTN) after methotrexate and folinic acid rescue (MTX/FA) resistance, treated alternately with carboplatin or etoposide as a second-line regimen. Retrospective cohort that included patients with failure of first-line MTX/FA regimen for low-risk GTN treated at Rio de Janeiro Federal University, Universidade Federal de São Paulo and Irmandade da Santa Casa de Misericórdia de Porto Alegre, from January/2010- December/2017. From 356 patients with low-risk GTN treated with MTX/FA, 75 (21.1%) developed resistance, of which 40 (53.3%) received Act- d , 23 (30.7%) carboplatin and 7 (9.3%) etoposide. Although patients treated with single-agent chemotherapy as a second-line regimen had comparable clinical and primary treatment characteristics, those treated with Act- d (80%, p = 0.033) or etoposide (71.4%, p = 0.025) had higher remission rates when compared with carboplatin (47.8%). Only 29% of patients treated with carboplatin received the chemotherapy cycles without delay compared to Act- d (98%, p < 0.001) or etoposide (85%, p = 0.009). Patients treated with carboplatin had significantly more hematological toxicity, notably anemia (30.4%, p = 0.008), lymphopenia (47.7%, p < 0.001) and thrombocytopenia (43.4%, p < 0.001), as well as a higher occurrence of febrile neutropenia (14.4%, p = 0.044) and vomiting (60%, p < 0.001) than those receiving Act- d (5%, none, 2.5%, none, 10%, respectively). Carboplatin did not have a satisfactory clinical response rate, likely due to severe hematological toxicity, which postponed chemotherapy. Our results reinforce the preference for Act- d as a second-line agent in patients with low-risk GTN after MTX/FA resistance. • Actinomycin- d and etoposide achieved higher remission rates than carboplatin as a second-line regimen for low-risk GTN. • Carboplatin caused more hematologic toxicity and treatment delays than actinomycin- d or etoposide. • Carboplatin required greater utilization of G-CSF for neutropenia than actinomycin- d. [ABSTRACT FROM AUTHOR]

Preclinical Research & Development Pancreatic cancer is the third leading cause of death in the US with a poor 5‐year survival rate of 8.5%. A novel anti‐cancer drug, dimethylamino parthenolide (DMAPT), is the water‐soluble analog of the natural sesquiterpene lactone, parthenolide. The putative modes of action of DMAPT are inhibition of the Nuclear chain factor kappa‐light‐chain enhancer of activated B cells (NFκB) pathway and depletion of glutathione levels; the latter causing cancer cells to be more susceptible to oxidative stress‐induced cell death. Actinomycin‐D (ActD) is a polypeptide antibiotic that binds to DNA, and inhibits RNA and protein synthesis by inhibiting RNA polymerase II. A phase 2 clinical trial indicated that ActD could be a potent drug against pancreatic cancer; however, it was not a favored drug due to toxicity issues. New drug entities and methods of drug delivery, used alone or in combination, are needed to treat pancreatic cancer more effectively. Thus, it was postulated that combining DMAPT and ActD would result in synergistic inhibition of Panc‐1 pancreatic cancer cell growth because DMAPT's inhibition of NFκB would enhance induction of apoptosis by ActD, via phosphorylation of c‐Jun, by minimizing NFκB inhibition of c‐Jun phosphorylation. Combining these two drugs induced a higher level of cell death than each drug alone. A fixed drug ratio of DMAPT: ActD (1,200:1) was used. Data from metabolic (MTT) and colony formation assays were analyzed for synergism with CompuSyn software, which utilizes the Chou‐Talalay equation. The analyses indicated synergism and moderate synergism at combination concentrations of DMAPT/ActD of 12/0.01 and 18/0.015 μM, respectively. [ABSTRACT FROM AUTHOR]

Aims and Objectives: To study the clinical presentations of gestational trophoblastic neoplasia and its response to chemotherapy. Materials and Methods: This is a retrospective study of 28 women of gestational trophoblastic neoplasia evaluated over a period of 6 years from January 2004 to December 2009. Patients were evaluated on the basis of their age, number of deliveries, history of abortion or molar pregnancy, and the treatment received. All patients were scored on the basis of WHO scoring system. Patients with low risk (score /=7) received multiple agent chemotherapy with EMACO regimen. After completion of chemotherapy patients were followed for a minimum of 2 years. The response to treatment was evaluated during follow-up by clinical examination, beta hCG levels and imaging as and when required. Results: Out of 28 women only 27 could be evaluated, because 1 patient was lost to follow-up. Out of 27 patients, 18 patients (66.67%) achieved complete remission with the first-line chemotherapy and additional 25.92% (7/27) achieved complete remission with second line chemotherapy resulting in complete remission of 92.5% (25/27). Conclusion: Gestational trophoblastic neoplasia is curable if patient is properly evaluated and scored. It shows good response to chemotherapy.

The aim of the present study was to isolate potent anticancer compound from actinomycetes strain SRP18 isolated from soil of high altitude region of Thajiwas glacier, Sonamarg Kashmir-India. The potential isolate SRP18 was identified as Streptomyces tauricus on the basis of 16S rDNA sequence technique. The large scale cultivation of potent strain, Streptomyces tauricus SRP18 and subsequent isolation and purification by a series of chromatographic techniques resulted in isolation of potent anticancer compound. Structure elucidation of potent compound by using various spectroscopic techniques including NMR was confirmed to be actinomycin-D. As such, this is the first report of a strain of S. tauricus capable of producing this bioactive compound. The isolated compound was evaluated for its cytotoxicity potential against four human cancer cell lines like HeLa, PC-3, THP-1, and Caco-2 and showed a potent activity with IC range of 4.91-7.25 µM. [ABSTRACT FROM AUTHOR]

Gestational Trophoblastic Neoplasia (GTN) is a term used for a group of malignant gynecological tumors including choriocarcinoma. Low-risk neoplasias can be cured using single agents Methotrexate (MTX) and actinomycin-D (ACD), but in certain cases, decreased responsiveness and serious side effects occur. Therefore, researchers have been attempting to find new treatment modalities. One of the most popular way for increasing cancer patient survival rates is supporting treatment with adjuvant molecules or chemosensitizers. For this purpose, we investigated epigallocatechin-3-gallate (EGCG), a green tea cathecin, and Erlotinib, an EGFR tyrosine kinase inhibitor, as single agents and combined with MTX or ACD. In accordance with this, JAR (human placenta choriocarcinoma) cell line was used as an in vitro model and MTT, LDH, caspase-3 activation, RT-PCR, and Western Blot analyses were performed to investigate the effects of the test materials. Our studies demonstrate that combination of Erlotinib and EGCG with MTX and ACD decreases JAR cell proliferation and metastatic HER2 protein synthesis and increases caspase-3 activation compared to ACD or MTX alone. In addition, significant increase was observed in the apoptotic Bax gene, but no notable protein synthesis occurred in the Western Blot analysis, which suggests that combination of Erlotinib and EGCG with classical chemotherapeutics ACD or MTX may lead the JAR cells to apoptosis, but not by a mitochondrial pathway. All the results indicate that the synergetic effect of Erlotinib and EGCG with classical chemotherapeutics may help to increase patient survival rates of choriocarcinoma, but the detailed mechanism needs further investigation. [ABSTRACT FROM AUTHOR]

As part of the endeavor for search of effective bioactive compounds, an untapped Arabian Sea environment is selected as a sampling source for the isolation of chemically-talented actinomycete strains. We have isolated an actinomycete strain from the sea sediments belonging to the genus Streptomyces (Accession No. KJ020688) with having potent cytotoxicity (84 %) against brine shrimps nauplii. Isolated strain also showed substantial antibacterial activity against Bacilus subtilis, Escherichia coli and Acinetobacter test strains. Fractions with significant antitumor activity obtained from the extract of 20 l fermentation broth were structurally elucidated and revealed with the production of compounds named as iturin A and actinomycin-D. The cyclic lipopeptide iturin A display outstanding novel antitumor activities against three tumor cell lines viz. HeLa, MCF-7, Hep G2 with IC values of 1.73 ± 0.9, 6.44 ± 0.6 and 8.9 ± 1.09 μg/ml respectively. This peptide is found to be ineffective against RD tumor cells. The second polypeptide actinomycin-D is found to be active against the entire panel of tumor cell lines used. It exhibited stronger activities with IC-values of <0.9 μg/ml against HeLa and MCF-7, while 11.72 ± 0.9 and 1.19 ± 0.8 against Hep G2 and RD cells respectively. Results from the culture optimization experiments of this strain showed greater yield of secondary metabolites while culturing in glucose-yeast extract-malt extract (M2) medium under culture conditions set as follows, shaking at 95 rpm, pH 7.8, incubation temperature 28 °C, for 168 h. As such this is the first report for the isolation of any iturin family member from actinomycetes group with having antitumor activity. [ABSTRACT FROM AUTHOR]

Aims: The objective of this study was to determine the clinical presentation of GTD and response of GTN to single and multiple agent chemotherapy on the basis of WHO Prognostic risk scoring system. Methods: This was a cross-sectional retrospective study undertaken at Paropakar Maternity and Women's Hospital. The medical records of 102 GTD cases were reviewed from January 25, 2015 to January 24, 2016. Data pertaining patient characteristics, histopathology types of GTD, management, prognostic risk scores, chemotherapy, follow up and remissions were retrieved and were analyzed using SPSS version 16.0. Results: Among 102 GTD cases, the most common presentation was vaginal bleeding 69(67.6%) followed by ultrasound diagnosed cases 30(29.4%). Primary management of all cases were suction evacuation, 68 completed and 12 are under follow-up. GTN was diagnosed in 14/90 (15.5%) of complete mole and 5/90 (5.5%) of partial mole. Twenty-two cases received chemotherapy for persistent gestational trophoblastic tumour(19) and invasive mole(3). Twenty cases were low risk score group and two cases under high risk group. Out of 20 low risk cases that received MTX-FA, 13/20 (65%) achieved remission. Due to low response of MTX-FA, five of them were converted to Actinomycin-D and achieved remission(100%). Two high risk cases received EMA-CO regimen and achieved 100% remission. Two low risk GTN, complete and invasive mole (underwent hysterectomy) are undergoing MTX-FA chemotherapy. Conclusions: The most common presentation of GTD was vaginal bleeding. Low risk GTN achieved 65% remission with Methotrexate-Folinic acid, ultimately achieved 100% remission with Actinomycin-D. High risk GTN achieved 100% remission with EMA-CO regimen. [ABSTRACT FROM AUTHOR]

A highly potent secondary metabolite producing endophytic strain, Streptomyces sp. HUST012 was isolated from the stems of the medicinal plant Dracaena cochinchinensis Lour. Strain HUST012 showed antimicrobial and antitumor activities which were significantly much higher than those of dragon's blood extracted from D. cochinchinensis Lour. On further analysis, the strain was found to produce two metabolites, SPE-B11.8 (elucidated to be a novel metabolite (Z)-tridec-7-ene-1,2,13-tricarboxylic acid) and SPE-B5.4 (elucidated as Actinomycin-D). The Minimum Inhibitory Concentration values of SPE-B11.8 against a set of test bacterial organisms (Methicillin-resistant Staphylococcus epidermis ATCC 35984, Methicillin-resistant Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Klebsiella pneumoniae ATCC 13883) ranged between 15.63 and 62.5 µg/ml while that for SPE-B5.4 ranged between 0.04 and 2.24 µg/ml. The compound SPE-B11.8 showed cytotoxic effect at 41.63 and 29.54 µg/ml IC50 values against Hep-G2 and MCF-7 respectively, while the compound SPE-B5.4 exhibited stronger activities against them at 0.23 and 0.18 μg/ml IC50 values.

The high mobility group box 1 protein has been identified as a key player in chromatin homeostasis including transcription regulation, recombination, repair, and chromatin remodeling. Emerging findings indicate HMGB1 protein over expression in nearly all types of human cancers and inflammatory disorders. Thus it is considered as a potential therapeutic target for treating various malignancies. We screened the promoter region of hmgb1 gene and selected a positive regulatory element of 25 base pair duplex (25RY) (−165 to −183) as a potential target for chemotherapeutic intervention. The molecular interaction of actinomycin (ACT) with the regulatory region of hmgb1 gene was characterized by spectroscopic, calorimetric and molecular docking studies. The hypochromic and bathochromic shift in the absorption spectrum, stabilization of 25RY duplex against thermal denaturation, perturbation of CD spectrum of duplex and enhancement of fluorescence intensity of actinomycin indicate strong binding of actinomycin to the hmgb1 promoter region (25RY).The energetics was characterized to be endothermic and entropy driven. All these results are in good agreement with in silico investigation that suggest minor groove binding with effective intercalation at GC bases of actinomycin to 25RY. This study identifies hmgb1 gene promoter region a potential target for the anticancer therapautiucs. [ABSTRACT FROM AUTHOR]

Objectives: Methotrexate (MTX) and Actinomycin-D (Act-D) are effective drugs used in the treatment of low-risk gestational trophoblastic neoplasia (LRGTNs). The aim of the present study was to compare intravenous (IV) MTX and IV Act-D in the treatment of LRGTNs. Materials and Methods: Sixty-two patients with LRGTN were enrolled in a prospective randomized clinical trial between 2010 and 2013 in Moheb e Yas Hospital, Tehran University of Medical Sciences. Primary treatment regimens were IV MTX, 0.4 mg/kg daily for 5 days every 14 days (25 mg maximum daily dose), and IV Act-D, 1.25 mg/m2(2 mg maximum dose) every 14 days. Results: Thirty-two and 30 patients were enrolled to MTX and Act-D groups, respectively. Complete remission after receiving first-line chemotherapy was achieved in 79% of all cases, 80% in the Act-D group and 78.1% in the MTX group. Twenty percent of the Act-D patients and 21.9% of the MTX patients showed resistance to the first-line chemotherapy, of which 16.7% and 15.6% responded completely to the second-line monotherapy, respectively. Multiple drug therapy was needed in 3.3% of the Act-D group and 6.3% of the MTX group. We did not find any correlation between treatment response and beta Yhuman chorionic gonadotropin level, uterine mass size, lung metastasis, antecedent pregnancy, and duration from diagnosis to treatment. Adverse effects were not statistically different between the 2 groups. Conclusions: Single-agent chemotherapy in the treatment of LRGTNs resulted in an overall complete remission rate of 79%, 80% in the Act-D group and 78.1% in MTX group, with no statistically significant difference. Whereas this study represents an important step in comparing single-agent treatments, comparison of other regimens will be required to determine the optimal single-agent therapy. [ABSTRACT FROM AUTHOR]

• ES treatment requires a multidisciplinary approach. • Deficiencies in treatment affect the results negatively. • This study showed that carboplatin can be used effectively as an alternative to actinomycin-D in the consolidation treatment. • In addition, the presence of metastasis at diagnosis, tumor originating from the soft tissue, advanced stage and progressive disease are the poor prognostic factors in ES. Treatment of Ewing sarcoma (ES) requires multidisciplinary approach and deficiencies in treatment adversely affect the results. This study included patients diagnosed with ES and aimed to determine the factors affecting prognosis and investigate the efficacy of replacing actinomycin-D with carboplatin in consolidation treatment. Eighty-two pediatric ES patients diagnosed at a single institution between 2005 and 2020 were retrospectively evaluated. Clinical and epidemiological features, treatment modalities, prognostic criteria, and overall survival (OS) rates of patients revieved. In consolidation treatment, 22 patients were treated with actinomycin-D and 32 patients with carboplatin (500 mg/m2/dose), 24 patients could not receive consolidation treatment. The 5- and 10-year OS rates of the patients were compared. The 5- and 10-year OS rates of the 82 patients with ES were 46% and 40%, respectively. The 5-year OS rates in the group with localized disease (n = 55) and metastasis (n = 27) at diagnosis were 54% and 26%, respectively (p = 0.006). When evaluated according to the consolidation treatment administered both the 5- and 10-year OS rates of the patients receiving actinomycin-D were 50%. The 5-year OS rate was 58% in the carboplatin group, and the 5- and 10-year OS rates of patients that did not receive consolidation treatment was 20%. Survival was significantly worse in the group that did not receive consolidation treatment. Furthermore, our results suggested that carboplatin could be used effectively as an alternative to actinomycin-D in ES consolidation treatment. [ABSTRACT FROM AUTHOR]

Highlights: [•] Both LTP and LTD are facilitated by novel spatial learning. [•] Learning-facilitated LTD is prevented by inhibition of gene transcription. [•] LTD and learning are both prevented by suppressing the immediate early gene c-fos. [•] These data support a role for LTD in the mechanisms underlying spatial learning. [ABSTRACT FROM AUTHOR]

Background: Isolated limb infusion (ILI) using cytotoxic agents has been demonstrated to be an effective and less invasive alternative modality than isolated limb perfusion for the treatment of melanoma localized to a limb. Percutaneous catheters were inserted into the axial artery and vein of the affected limb while using a pneumatic cuff to restrict limb vascular flow proximally to "isolate" the limb from the body and enable delivery of high-dose intra-arterial chemotherapy selectively to the limb. The ILI technique was developed at the Sydney Melanoma Unit (now renamed the Melanoma Institute Australia), and only a few other centers have reported separate results. We report our early results using the ILI technique for management of locally recurrent surgically nonresectable melanoma. Methods and results: Twenty-eight ILI procedures were performed in 20 patients treated with one or more procedures between 1997 and 2007. Patient parameters and clinical responses were evaluated. The median follow-up duration was 15.9 months after the first ILI, with an overall response rate after one or more infusions of 70%, of which 35% were complete responders and 35% were partial responders, with a further 20% showing stable disease, giving a "clinically significant" response rate of 90%. After one ILI (n = 20), the overall response rate was 70%, with 20% complete responders and 50% partial responders, and 20% with stable disease. Low limb toxicities were generally observed, and no amputations were required. Conclusion: ILI chemotherapy is a useful technique, which can be readily repeated for control of melanoma in the limb. It is generally well tolerated, and is capable of achieving a cure, delayed progression, or effective palliation in selected cases. The longest survivors in this series were 8 and 10 years from the last ILI. [ABSTRACT FROM AUTHOR]

Background: During mitosis most nucleolar proteins redistribute to other locales providing an opportunity to study the relationship between nucleolar protein localization and function. Dictyostelium is a model organism for the study of several fundamental biological processes and human diseases but only two nucleolar proteins have been studied during mitosis: NumA1 and Snf12. Both of them are linked to the cell cycle. To acquire a better understanding of nucleolar protein localization and dynamics in Dictyostelium we studied the nucleolar localization of two additional proteins during mitosis: Snf12-linked forkhead-associated kinase A (FhkA), which is involved in the cell cycle, and Ca2+ -binding protein 4a (CBP4a), which is a binding partner of NumA1. Methods: Polyclonal antibodies were produced in-house. Cells were fixed and probed with either anti-FhkA or anti-CBP4a in order to determine cellular localization during interphase and throughout the stages of mitosis. Colocalization with DAPI nuclear stain allowed us to determine the location of the nucleus and nucleolus while colocalization with anti-α-tubulin allowed us to determine the cell cycle stage. Results: Here we verify two novel nucleolar proteins, Rad53 homologue FhkA which localized around the edge of the nucleolus and CBP4a which was detected throughout the entire nucleolus. Treatment with the Ca2+ chelator BAPTA (5 mM) showed that the nucleolar localization of CBP4a is Ca2+ -dependent. In response to actinomycin D (0.05 mg/mL) CBP4a disappeared from the nucleolus while FhkA protruded from the nucleus, eventually pinching off as cytoplasmic circles. FhkA and CBP4a redistributed differently during mitosis. FhkA redistributed throughout the entire cell and at the nuclear envelope region from prometaphase through telophase. In contrast, during prometaphase CBP4a relocated to many large, discrete "CBP4a islands" throughout the nucleoplasm. Two larger "CBP4a islands" were also detected specifically at the metaphase plate region. Conclusions: FhkA and CBP4a represent the sixth and seventh nucleolar proteins that have been verified to date in Dictyostelium and the third and fourth studied during mitosis. The protein-specific distributions of all of these nucleolar proteins during interphase and mitosis provide unique insight into nucleolar protein dynamics in this model organism setting the stage for future work. [ABSTRACT FROM AUTHOR]

Dictyostelium is a model eukaryote for the study of several cellular processes; however, comparatively little is known about its nucleolus. Identification of nucleolar proteins is key to understanding this nuclear subcompartment, but only four have been identified in Dictyostelium. As discussed in this article, a potential relationship between nucleolar NumA1 and BAF60a/SMARCD1 suggested BAF60a may also reside in the nucleolus. Here, we identify BAF60a homologue Snf12 as the fifth nucleolar protein in Dictyostelium. Immunolocalization experiments demonstrate that Snf12 is nucleoplasmic, but translocates to nucleoli upon actinomycin-D-induced transcription inhibition (0.05 mg/mL, 4 h). Translocation was accompanied by a microtubule-independent protrusion of nucleolar Snf12 regions from the nucleus followed by detection of Snf12 in cytoplasmic circles for at least 48 h. Residues KRKR are both necessary and sufficient for nucleoplasmic localization of Snf12 and represent a functional nuclear localization signal (NLS), similar to recently identified NLSs in other Dictyostelium proteins. Since nucleolar and nucleoplasmic proteins redistribute during mitosis, we investigated Snf12 dynamics during this time. Dictyostelium undergoes closed mitosis, meaning its nuclear envelope remains intact. Despite this, during metaphase and anaphase Snf12 redistributed throughout the cytoplasm before reaccumulating in the nucleus during telophase, unlike the previously reported nucleoplasmic redistribution of nucleolar NumA1. The nuclear exit of Snf12 was independent of its putative nuclear export signal and not inhibited by exportin inhibition, suggesting that the redistribution of nuclear proteins during mitosis in Dictyostelium is mediated by other mechanisms. Snf12 is the second Dictyostelium nucleolar protein for which its dynamics during mitosis have been investigated. [ABSTRACT FROM AUTHOR]

Background: The binding of drugs to catheters can be a source variation in dosing chemotherapeutics. Drug contamination from the dosing central venous line (CVL) can impact the reporting of pharmacokinetic (PK) results and analysis. Peripheral venipuncture avoids binding complications from the CVL but dissuades patients from enrolling. Our group has developed a catheter clearing procedure to minimize the extent of contamination so that dosing and sampling from the CVL can ensue, promoting patient willingness to participate in phase I pediatric oncology trials. Objectives: To develop a population pharmacokinetic model of actinomycin-D (AMD) in children with cancer incorporating expressions for drug contamination from PK samples obtained via indwelling CVLs and to evaluate the efficiency of a catheter clearing procedure in removing contamination as well as the impact of contamination on PK results. Methods: A dataset of 199 AMD plasma concentration measurements from 36 patients (age 1.6-20.3 years) was analyzed using nonlinear mixed-effects modeling. Quantitative modeling approaches, including baseline contamination model, covariate model, and catheter clearance model, were evaluated to describe catheter contamination. Monte Carlo simulations mimicking a prospective study in children with cancer were performed to assess the performance of the final model and impact of catheter contamination on PK reporting. Results: The PK of AMD was best described by a linear 3-compartment model with first-order elimination. A baseline contamination model including a contamination factor proportional to the model-predicted concentration for samples obtained from central catheters was chosen as the most parsimonious and accurate among competing models. The final model parameters were allometrically scaled to a 70 kg person. The estimated mean parameter values were 11 L/h, 5.79, 24.2, 490 L, 17.7, and 42.8 L/h for total clearance, central volume of distribution, peripheral volume 1, peripheral volume 2, inter-compartmental clearance 1, and inter-compartmental clearance 2, respectively. The proportional contamination factor was 19.3 % immediately post-drug administration and decreased at a first-order rate of 0.0932 h. Simulations precisely re-estimated kinetic parameters with catheter contamination adjustment. Large uncertainty and poor estimation were observed when contamination was ignored. Conclusions: Drug contamination from sampling catheter can impact AMD PK results and should be accounted for in the analysis. We provide a framework for evaluating catheter contamination and guidance on adjustment in the PK model. [ABSTRACT FROM AUTHOR]

The calmodulin-binding protein nucleomorphin isoform NumA1 is a nuclear number regulator in Dictyostelium that localizes to intra-nuclear patches adjacent to the nuclear envelope and to a lesser extent the nucleoplasm. Earlier studies have shown similar patches to be nucleoli but only three nucleolar proteins have been identified in Dictyostelium. Here, actinomycin-D treatment caused the loss of NumA1 localization, while calcium and calmodulin antagonists had no effect. In keeping with a nucleolar function, NumA1 moved out of the presumptive nucleoli during mitosis redistributing to areas within the nucleus, the spindle fibers, and centrosomal region before re-accumulating in the presumptive nucleoli at telophase. Together, these data verify NumA1 as a true nucleolar protein. Prior to this study, the dynamics of specific nucleolar proteins had not been determined during mitosis in Dictyostelium. FITC-conjugated peptides equivalent to presumptive nuclear localization signals within NumA1 localized to nucleoli indicating that they also act as nucleolar localization signals. To our knowledge, these represent the first precisely defined nucleolar localization signals as well as the first nuclear/nucleolar localization signals identified in Dictyostelium. Together, these results reveal that NumA1 is a true nucleolar protein and the only nucleolar calmodulin-binding protein identified in Dictyostelium. The possible use of nuclear/nucleolar localization signal-mediated drug targeting to nucleoli is discussed. [ABSTRACT FROM AUTHOR]

Aims: To isolate and characterize bioactive metabolites produced by a micro-organism isolated from a soil sample associated with the roots of a medicinal plant, Azadirachta indica. Methods and Results: Morphological, cultural, physiological and 16S rRNA homology studies revealed that the organism showed 99% similarity with Streptomyces griseoruber NBRC 12873. One bioactive metabolite (Py2) isolated from the fermented broth was characterized as actinomycin-D (act-D). It showed high activity against various Gram-positive and Gram-negative bacterial cultures, Mycobacterium tuberculosis H37Rv and human neoplastic cells in vitro using standard protocols. Conclusions: The isolated strain S. griseoruber produced act-D predominantly (210 mg l−1, c. 88% of the crude) under nonoptimized growth conditions. Significance and Impact of the Study: Streptomyces griseoruber may be exploited as a potential source for the commercial production of act-D, as this strain is not reported to produce act-D. Further investigations on the strain for commercial application will be of immense pharmaceutical importance. [ABSTRACT FROM AUTHOR]

A sensitive, specific and efficient high-performance liquid chromatography-tandem mass spectrometry assay for the simultaneous determination of vincristine and actinomycin-D in human dried blood spots is presented. Dried blood spots were punched out of a collection paper with a 0.25-in.-diameter punch. The analytes were extracted from the punched-out disc using sonication during 15 min in a mixture of acetonitrile–methanol–water (1:1:1, v/ v/ v) containing the internal standard vinorelbine. Twenty-microlitre volumes were injected onto the HPLC system. Separation was achieved on a 50 × 2.1 mm ID Xbridge C18 column using elution with 1 mM ammonium acetate–acetonitrile (70:30, v/ v) adjusted to pH 10.5 with ammonia and run in a gradient with methanol at a flow rate of 0.4 mL/min. HPLC run time was 6 min. The assay quantifies vincristine from 1 to 100 ng/mL and actinomycine-D from 2 to 250 ng/mL using a blood sample obtained by a simple finger prick. Validation results demonstrate that vincristine and actinomycin-D can be accurately and precisely quantified in human dried blood spots with the presented method. The assay can now be used to support clinical pharmacologic studies with vincristine and actinomycin-D. [ABSTRACT FROM AUTHOR]

Objective: To optimize the L-carnitine (LC) concentration as a supplement in embryo culture medium and to investigate the effect of LC on developing embryos. Design: Experimental study. Setting: Reproductive research center at a tertiary hospital. Intervention(s): To optimize the LC concentration, 420 mouse embryos were divided into seven groups and incubated with different LC concentrations (0, 0.3, 0.6, 1.2, 2.5, 5.0, and 10 mg/mL). To investigate the effect of LC on the developing embryos, 500 mouse embryos were divided into three groups and incubated with either actinomycin-D (AD; 0.005 μg/mL), hydrogen peroxide (H2O2; 500 μmol/L), or tumor necrosis factor α (TNF-α; 500ng) with and without LC 0.3 or 0.6 mg/mL. Blastocyst development rate (%BDR) and DNA damage were examined for all groups. Main Outcome Measure(s): Effect of LC on embryogenesis. Result(s): Significant improvement in %BDR was seen at LC 0.3 mg/mL compared with the control (p = 0.006). L-Carnitine at 0.3 and 0.6 mg/mL significantly reduced the blocking effect of AD, H2O2, and TNF-α and significantly decreased the level of DNA damage. Conclusion(s): Embryo culture medium supplementation with LC may offer a novel and a cost-effective technique to improve the embryogenesis of cultured embryos. This may be beneficial in improving IVF outcomes. [Copyright &y& Elsevier]

Ascoviruses (AVs) induce a unique pathology in their insect host cells causing cleavage of the cells into virion-containing vesicles. The mechanism by which AVs induce vesicle formation is poorly understood. It is postulated that the virus initially induces apoptosis leading to cell fragmentation. The apoptotic bodies are however, rescued by the virus to form the vesicles. Here we show that Heliothis virescens AV (HvAV-3e) is able to inhibit chemically induced apoptosis from around 16 h after infection. Analysis of the genome of the virus indicated the presence of a putative inhibitor of apoptosis ( orf28) gene that encodes a protein with an imperfect baculovirus inhibitor of apoptosis repeat (BIR) and a RING domain. Transiently expressed orf28 did not inhibit chemically induced apoptosis suggesting that the protein may not serve as an inhibitor of apoptosis. Nevertheless, RNA interference studies revealed that the gene is probably essential for virus pathology and replication. [ABSTRACT FROM AUTHOR]

Isolated limb infusion (ILI) is a minimally invasive technique for delivering regional chemotherapy in patients with advanced and metastatic melanoma confined to a limb. It is essentially a low-flow isolated limb perfusion (ILP) performed via percutaneous catheters without oxygenation. From our prospective database 185 patients with advanced metastatic melanoma of the limb treated with a single ILI between 1993 and 2007 were identified. In all patients a cytotoxic drug combination of melphalan and actinomycin-D was used. Drug circulation time was 20–30 min under mild hyperthermic conditions (38–39°C). The majority of patients (62%) were female. Their average age was 74 years (range 29–93 years). Most patients had MD Anderson stage III disease (134/185). The overall response rate was 84% [complete response (CR) rate 38%, partial response rate 46%]. Median response duration was 13 months (22 months for patients with CR; P = 0.01). Median follow-up was 20 months and median survival was 38 months. In those patients with a CR, the median survival was 53 months ( P = 0.005). CR rate and survival time decreased with increasing stage of disease. On multivariate analysis significant factors for a favorable outcome were achievement of CR, stage of disease, thickness of primary melanoma, the CO2 level in the isolated circuit, and a Wieberdink limb toxicity score of III (considerable erythema and edema). The response rates and duration of response after ILI are comparable to those achieved by conventional ILP. ILI is a minimally invasive alternative to the much more complex and morbid conventional ILP technique for patients with advanced metastatic melanoma confined to a limb. [ABSTRACT FROM AUTHOR]

An actinomycete strain, designated as C-5, was isolated from the soil sample collected from steel plant effluent sediment. The strain produced actinomycin-D in substantial quantities (80 mg/L). The strain C-5 was taxonomically characterised on the basis of morphological and phenotypic characteristics, genotypic data and phylogenetic analysis. A nearly complete 16S rRNA sequence of the isolate was determined and found to have 100% identity with Streptomyces sindenensis. Streptomyces sindenensis is not reported earlier to produce actinomycin-D. Anticancer activities were determined against various human cancer cell lines. Production of actinomycin-D was scaled up in bench scale fermentors and optimised to a titre of 120 mg/L. [ABSTRACT FROM AUTHOR]

Abstract: It is well known that inflammatory and infectious conditions differentially regulate cytochrome P450 (P450)-mediated drug metabolism in the liver. We have previously outlined a potential pathway for the downregulation in hepatic cytochrome P450 following LPS-mediated inflammation in the CNS (Abdulla, D., Goralski, K.B., Garcia Del Busto Cano, E., Renton, K.W., 2005. The signal transduction pathways involved in hepatic cytochrome P450 regulation in the rat during an LPS-induced model of CNS inflammation. Drug Metab. Dispos). The purpose of this study was to outline the effects of LPS-induced peripheral and central nervous system inflammation on hepatic cytochrome P450 2E1 (CYP2E1) in vivo, an enzyme that plays an important role in various physiological and pathological states. We report an increase in hepatic mRNA expression of CYP2E1 that occurred as early as 2–3 h following either the intraperitoneal (i.p.) injection of 5 mg/kg LPS or i.c.v. administration of 25 μg of LPS. This increase in CYP2E1 mRNA expression was sustained for 24 h. In sharp contrast to the increase in hepatic CYP2E1 mRNA, we observed a significant reduction in the catalytic activity of this enzyme 24 h following either the i.c.v. or i.p. administration of LPS. Cycloheximide or actinomycin-D did not change the LPS-mediated downregulation in hepatic CYP2E1 catalytic activity. Our results support the idea that LPS acts at two different levels to regulate hepatic CYP2E1: a transcriptional level to increase CYP2E1 mRNA expression and a post-transcriptional level to regulate CYP2E1 protein and activity. [Copyright &y& Elsevier]

Actinomycin-D (Act-D) and vincristine (VCR) are cytotoxic agents commonly used in the treatment of pediatric cancers. To date, there are few published methods on quantifying Act-D or VCR and no published methods on quantifying the two drugs together. We present a methodology for the simultaneous quantification of Act-D and VCR in human plasma using liquid chromatography-tandem mass spectrometry (LC/MS/MS) detection. Following solid phase extraction, plasma samples were separated and analyzed using electrospray ionization (ESI). The lower limit of quantitation (LLOQ) for both Act-D and VCR was 0.5 ng/ml. The analytical accuracy for detection of both Act-D and VCR was ≥ 90%. The analytical precision, as estimated by the coefficient of variation was ≤ 6% for Act-D and ≤ 11% for VCR. Given the prevalence of the use of the two drugs as combination therapy in a variety of pediatric oncological indications, the small sample volume requirements and the assay sensitivity, this methodology is expected to support several ongoing and future pediatric trials. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the process of memory consolidation following classical conditioning of earthworms. Earthworms were conditioned in paired trials by a weak vibration as a conditioned stimulus (CS), and by light as an unconditioned stimulus (US). The occurrence of a shrinking response upon exposure to the CS increased steadily with the number of paired training trials. When the training procedure was changed by increasing the intertrial interval (ITI), it was found that only those worms trained with a 68s ITI exhibited long-term memory retention for at least 24h. The influence of mRNA synthesis inhibition by actinomycin-D or of protein synthesis by anisomycin on memory consolidation was also examined. Induction of the long-term memory was blocked when either of these two compounds was injected into the body cavity of the worm within 25min of conditioning with the 68s ITI. These results demonstrate that the long-term memory is dependent upon protein synthesis in response to the upregulation of new transcription messengers. [Copyright &y& Elsevier]

To identify the novel mechanism by which nitric oxide (NO) suppresses flavin-containing monooxygenase (FMO) activity in endotoxemic rat livers, NO-overproducing conditions were induced in primary cultured rat hepatocytes by treatment with a mixture (LCM) of lipopolysaccharide and proinflammatory cytokines (IL-1β, TNF-α, and IFN-γ), or by the addition of a pure NO donor, spermine–NONOate. mRNA levels of the major hepatic form, FMO1, decreased via a cGMP-independent destabilizing effect of NO rather than by decreased transcription. The decrease in the mRNA levels caused by LCM-induced inducible NO synthase (iNOS) was completely blocked by co-treatment with aminoguanidine, a selective iNOS inhibitor. Furthermore, spermine–NONOate, but not the cGMP analog, 8-bromo-cGMP, dose- and time-dependently attenuated FMO1 mRNA stability in actinomycin-D-pretreated cells, resulting in decreases in protein levels and biochemical activity. These results suggest that NO acts directly in a cGMP-independent mechanism by decreasing the half-life of FMO1 mRNA, thereby inducing impairment of FMO-related functions in endotoxemia. [Copyright &y& Elsevier]

Objective: To investigate the expression of tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptors in cultured synovial fibroblasts from rheumatoid arthritis (RA) and osteoarthritis (OA) patients, and to examine their susceptibility to TRAIL-induced apoptosis in the presence or absence of metabolic inhibitors. Methods: The expression of TRAIL receptors in synovial fibroblasts was examined by Western blot and immunohistochemistry. Expression of TRAIL-receptor 1 (TRAIL-R1), FLICE-inhibitory protein (Fas-associating protein with death domain-like interleukin-1-converting enzyme), and Bcl-2 was assessed by Western blot. Synovial cell viability was measured by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay (XTT), and apoptosis was determined both by DNA content analysis after propidium iodide staining and Annexin V stain. Results: TRAIL-R1 was constitutively expressed on cultured synovial fibroblasts from RA and OA, however, expression of TRAIL-R2 and TRAIL-R3 was not observed by immunohistochemistry and Western blot. Cultured synovial fibroblasts were resistant to apoptosis by TRAIL alone, but combined treatment of TRAIL with actinomycin D (ActD: 200 ng/mL), cycloheximide (CHX: 10 μg/mL), or proteasome inhibitor (MG132: 20 μM) induced apoptosis in a dose-dependent manner. The apoptosis was completely or partially inhibited by various caspase inhibitors, implicating an involvement of caspase pathway in TRAIL-induced apoptosis in the presence of these metabolic inhibitors. Expression of TRAIL-R1, FLIP L , and Bcl-2 did not account for the apoptosis by the combined treatment of TRAIL with ActD. Conclusions: Although TRAIL-R1 was constitutively expressed; cultured synovial fibroblasts were resistant to apoptosis by TRAIL. ActD, CHX, and MG132 rendered cultured synovial fibroblasts susceptible to TRAIL-induced apoptosis by a caspase-dependent mechanism. However, the exact mechanism of sensitization by these metabolic inhibitors remains to be determined. [ABSTRACT FROM AUTHOR]

The interaction of actinomycin (ACTD) with double stranded (ds) calf thymus DNA and single stranded (ss) DNA was studied at the carbon paste electrode surface by means of transfer voltammetry in 0.2 M phosphate buffer solution (pH 7.4). Accordingly the interaction of actinomycin (ACTD) with ds calf thymus DNA, ss DNA and supercoiled (sc) DNA was studied using hanging mercury drop electrode in 0.3 M NaCl, and 50 mM sodium phosphate buffer (pH 8.5). The different electrochemical behaviours are presented and compared in the article. [Copyright &y& Elsevier]

Inhibitors of protein and mRNA syntheses inhibit long-term memory (LTM), but we lack information about the time windows during which those inhibitors are effective.Anisomycin (a protein synthesis translation inhibitor) was given to Hermissenda crassicornis which had received sufficient Pavlovian conditioning to produce LTM. When tested after 90 min, LTM recall was blocked when anisomycin was administered until 13 min after conditioning and from 65 to 75 min. There was good recall from 16 to 60 min.When tested at 240 min, two periods of sensitivity to anisomycin were revealed: one finished before 20 min, while the other lasted from 60 to 220 min.A brief study of the transcription inhibitor actinomycin-D found its action similar to that of anisomycin, except not inhibiting recall from about 160 to 220 min. [Copyright &y& Elsevier]

The biflagellate somatic cells of Volvox carterif nagariensis lyengar exhibit an asymmetric pattern of fiegeller development. Initially each somatic cell has two short (4 μm) flagella but after several hours one.flagellum on each cell elongates until it reaches a length of 12 μm. Due to the regular arrangement of somatic cells in the Voivox spheroid it is apparent that the same fiagellum on each somatic cell is the first to elongate. The asymmetric glagellar length is maintained for about 8 h after which the second flagellum on each somatic cell elongates. When the second flagellum attains the same length (12 μm) as the first flagellum, both flagella elongate at the same rate until reaching a final length of 22 μm. Experimental return,al of somatic cell flagella results in their regeneration. Somatic cells regenerate both flagella simultaneously and full length flagella are produced in about 2 h. The initial rate of flagellar regeneration is about ten times faster than the initial rate of flagellar growth in development. Cycloheximide. an inhibitor of protein synthesis, has no effect on the initial rate of flagellar regeneration but the flagella produced in the presence o[ the drug are half the length of flagella produced in its absence. Somatic cells are able to regenerate flagella up to the time of cell death. Deflngellation greatly enhances the synthesis of α and β tubulin, the major structural proteins of the flagellar axoneme, and other cellular proteins. [ABSTRACT FROM AUTHOR]

Aqueous leaf extract of Chenopodium ambrosoides prevented infection of tobacco mosaic and sunnhemp rosette viruses when applied to the leaves by increasing the resistance of the host plants. The leaf extract, however, did not inhibit lesion production in C. amaranticolor. The leaf extract induced only localized resistance in many hypersensitive hosts. Lesion production was considerably decreased when the leaf extract was applied to the under surface of leaves and virus challenge inoculated on the upper surface. The inhibitory activity of the leaf extract was reversed by simultaneous application of metabolic inhibitor, Actinomycin-D. The leaf extract was active both at acidic and basic pH. [ABSTRACT FROM AUTHOR]

Synthesis of plasma albumin was studied in perfused liver of normal and CCl-intoxicated rats, usingC-bicarbonate method. [ABSTRACT FROM AUTHOR]

Previous reports have confirmed that steroid hormones modulate the expression of adrenergic receptors on the surface of smooth muscle myocytes. The present study was undertaken to evaluate the mechanism by which testosterone modulates alpha-1 adrenergic receptor expression in the DDT MF-2 transformed smooth muscle cell. Utilizing H-prazosin radioligand binding studies, alpha-1 adrenergic receptors were noted to increase more than 2 fold in response to incubation with 10 M testosterone for 96 hours. Dihydrotestosterone similarly stimulated a significant increase in alpha-1 receptors; whereas, estradiol and hydrocortisone appeared to suppress the expression of this receptor in DDT myocytes. The testosterone effect was dose related with a maximal response observed in response to 10 M testosterone at both 48 and 96 hours. Kinetic experiments utilizing 10 M testosterone demonstrated a peak effect on alpha-1 receptor expression at 96 hours, and maintenance of the effect for at least 168 hours (7 days). The testosterone effect was completely prevented at both 48 and 96 hours by inhibition of transcription with actinomycin-D, or inhibition of translation with cycloheximide. Consistent with the receptor binding studies, RNA blotting studies have demonstrated maximal alpha-1 receptor mRNA levels at 48-96 hours of testosterone stimulation. In conclusion, these in vitro experiments have confirmed that physiologic concentrations of testosterone stimulate the increased expression of alpha-1 receptors in the DDT MF-2 myocyte after a delay of 48-96 hours; and that this effect appears to be mediated by transcription, translation, and synthesis of new proteins in these genital tract myocytes. [ABSTRACT FROM AUTHOR]