Mode-Dependent Antiviral Activity of Medicinal Plant Extracts against the Mosquito-Borne Chikungunya Virus.

The lack of specific treatment for chikungunya fever makes the need for anti-chikungunya virus agents more crucial. This study was conducted to evaluate 132 extracts obtained by sequential solvent extraction from 21 medicinal plants for cytopathic effect inhibitory activity using virus-infected Vero cells in two different sample introduction modes. Among the extracts, 42 extracts (31.8%) from 12 plants in the concurrent mode and three extracts (2.3%) from a plant in the non-concurrent mode displayed strong cytopathic effect inhibitory activity (cell viability ≥70%). Viral load quantification analysis unveiled that the extracts of Clinacanthus nutans (chloroform, ethyl acetate, and ethanol), Hydrocotyle sibthorpioides (ethanol), and Ocimum americanum (ethanol and methanol) hindered the release of viral progeny from the infected cells while the extracts of Ficus deltoidea (ethanol), Gynura bicolor (water), H. sibthorpioides (water), and O. americanum (chloroform and ethyl acetate) blocked the entry of virus into the cells. The extracts of Diodella sarmentosa (ethyl acetate), Diplazium esculentum (chloroform, ethyl acetate, and ethanol), and G. bicolor (ethanol) possessed virucidal effect and caused 5.41-log to 6.63-log reductions of viral load compared to the virus control. The results indicate that these medicinal plants are potential sources of anti-chikungunya virus agents that have varied modes of action.

Therapeutic Implication of Genomic Landscape of Adult Metastatic Sarcoma.

PURPOSE: This study investigated therapeutic potential of integrated genome and transcriptome profiling of metastatic sarcoma, a rare but extremely heterogeneous group of aggressive mesenchymal malignancies with few systemic therapeutic options. METHODS: Forty-three adult patients with advanced or metastatic non-GI stromal tumor sarcomas of various histology subtypes who were enrolled in the Personalized OncoGenomics program at BC Cancer were included in this study. Fresh tumor tissues along with blood samples underwent whole-genome and transcriptome sequencing. RESULTS: The most frequent genomic alterations in this cohort are large-scale structural variation and somatic copy number variation. Outlier RNA expression as well as somatic copy number variations, structural variations, and small mutations together suggest the presence of one or more potential therapeutic targets in the majority of patients in our cohort. Point mutations or deletions in known targetable cancer genes are rare; for example, tuberous sclerosis complex 2 provides a rationale for targeting the mammalian target of rapamycin pathway, resulting in a few patients with exceptional clinical benefit from everolimus. In addition, we observed recurrent 17p11-12 amplifications, which seem to be a sarcoma-specific event. This may suggest that this region harbors an oncogene(s) that is significant for sarcoma tumorigenesis. Furthermore, some sarcoma tumors carrying a distinct mutational signature suggestive of homologous recombination deficiency seem to demonstrate sensitivity to double-strand DNA-damaging agents. CONCLUSION: Integrated large-scale genomic analysis may provide insights into potential therapeutic targets as well as novel biologic features of metastatic sarcomas that could fuel future experimental and clinical research and help design biomarker-driven basket clinical trials for novel therapeutic strategies.

Antifungal and cytotoxic activities of selected medicinal plants from Malaysia.

This study was conducted to investigate the antifungal potential and cytotoxicity of selected medicinal plants from Malaysia. The extracts from the stem of Cissus quadrangularis and the leaves of Asplenium nidus, Pereskia bleo, Persicaria odorata and Sauropus androgynus were assayed against six fungi using p-iodonitrotetrazolium-based on colorimetric broth microdilution method. All the plant extracts were found to be fungicidal against at least one type of fungus. The strongest fungicidal activity (minimum fungicidal concentration=0.16 mg/mL) were exhibited by the hexane extract of C. quadrangularis, the hexane, chloroform, ethanol and methanol extracts of P. bleo, the hexane and ethyl acetate extracts of P. odorata, and the water extract of A. nidus. In terms of cytotoxicity on the African monkey kidney epithelial (Vero) cells, the chloroform extract of P. odorata produced the lowest 50% cytotoxic concentration (100.3 ± 4.2 µ g/mL). In contrast, none of the water extracts from the studied plants caused significant toxicity on the cells. The water extract of A. nidus warrants further investigation since it showed the strongest fungicidal activity and the highest total activity (179.22 L/g) against Issatchenkia orientalis, and did not cause any toxicity to the Vero cells.

Investigation of twenty selected medicinal plants from Malaysia for anti-Chikungunya virus activity.

Chikungunya virus is a reemerging arbovirus transmitted mainly by Aedes mosquitoes. As there are no specific treatments available, Chikungunya virus infection is a significant public health problem. This study investigated 120 extracts from selected medicinal plants for anti-Chikungunya virus activity. The plant materials were subjected to sequential solvent extraction to obtain six different extracts for each plant. The cytotoxicity and antiviral activity of each extract were examined using African monkey kidney epithelial (Vero) cells. The ethanol, methanol and chloroform extracts of Tradescantia spathacea (Commelinaceae) leaves showed the strongest cytopathic effect inhibition on Vero cells, resulting in cell viabilities of 92.6% ± 1.0% (512 µg/ml), 91.5% ± 1.7% (512 µg/ml) and 88.8% ± 2.4% (80 µg/ml) respectively. However, quantitative RT-PCR analysis revealed that the chloroform extract of Rhapis excelsa (Arecaceae) leaves resulted in the highest percentage of reduction of viral load (98.1%), followed by the ethyl acetate extract of Vernonia amygdalina (Compositae) leaves (95.5%). The corresponding 50% effective concentrations (EC50) and selectivity indices for these two extracts were 29.9 ± 0.9 and 32.4 ± 1.3 µg/ml, and 5.4 and 5.1 respectively. Rhapis excelsa and Vernonia amygdalina could be sources of anti-Chikungunya virus agents. [Int Microbiol 19(3):175-182 (2016)].

Antioxidant and cytotoxic activities of three species of tropical seaweeds.

BACKGROUND: Three species of seaweeds (Padina tetrastromatica, Caulerpa racemosa and Turbinaria ornata) are widely consumed by Asians as nutraceutical food due to their antioxidant properties. Studies have shown that these seaweeds exhibit bioactivities which include antimicrobial, antiviral, anti-hypertensive and anticoagulant activities. However, investigations into the mechanisms of action pertaining to the cytotoxic activity of the seaweeds are limited. The aim of this study was to determine the antioxidant and cytotoxic activities of whole extracts of P. tetrastromatica, C. racemosa and T. ornata, including the cellular events leading to the apoptotic cell death of the extract treated-MCF-7 cells. Bioassay guided fractionation was carried out and the compounds identified. METHODS: Powdered samples were sequentially extracted for 24 h. Their antioxidant activities were assessed by the DPPH radical, superoxide, nitric oxide and hydroxyl radical scavenging assays. The cytotoxic activity of the extract-treated MCF-7cells was assessed using the MTT assay. The most potent fraction was subjected to bioassay guided fractionation with column chromatography. All the fractions were tested for cytotoxic activity, caspase activity and effect on DNA fragmentation. RESULTS: All three seaweeds showed potent radical scavenging activities in the various assays. The activity of the cellular antioxidant enzymes, superoxide dismutase, catalase and glutathione reductase, in MCF-7 cells, decreased in a time-dependent manner. The partially purified fractions exhibited higher cytotoxic activity, as assessed by the MTT assay, than the whole extracts in the breast adenocarcinoma cell line, MCF-7. LC-MS analysis revealed the presence of bioactive alkaloids such as camptothecin, lycodine and pesudopelletierine. CONCLUSION: Based on the results obtained, all three seaweeds are rich sources of enzymatic and non-enzymatic antioxidants which could contribute to their reported medicinal benefits.

Bioactivity-guided isolation and structural characterization of the antifungal compound, plumbagin, from Nepenthes gracilis.

CONTEXT: Despite several phytochemical studies of Nepenthes gracilis Korth (Nepenthaceae), the biological activities of this pitcher plant remain to be explored. OBJECTIVE: This study evaluates the antifungal activity of N. gracilis extracts, isolates, and characterizes its bioactive compound and evaluates the cytotoxicity of the isolated compound. MATERIALS AND METHODS: Fresh leaves of N. gracilis were sequentially extracted. The fungistatic and fungicidal activities of the extracts were evaluated against six species of fungi of medical importance using a colorimetric broth microdilution method. The most active extract was fractionated by liquid-liquid partitioning and further purified by a preparative thin layer chromatography. Structural elucidation was carried out using FT-IR, GC-MS, and NMR. Cytotoxicity testing against rhesus monkey kidney epithelial cells (LLC-MK2) was assessed by a neutral red uptake (NRU) assay. RESULTS: The hexane extract, which showed the lowest minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), both at 20 µg/mL against Candida albicans, Issatchenkia orientalis, and Trichophyton mentagrophytes, was subjected to bioactivity-guided fractionation. The isolated compound exhibited potent activity with the MIC values ranging from 2 to 31 µg/mL against all the fungi. The active compound was identified as plumbagin (5-hydroxy-2-methyl-naphthalene-1,4-dione). The 50% cytotoxicity concentration (CC50) of plumbagin was 0.60 µg/mL. DISCUSSION AND CONCLUSION: The selectivity indices of plumbagin against all the fungi were less than 1.0, indicating that plumbagin is more toxic to mammalian than fungal cells. This study provides information on the antifungal properties of N. gracilis leaf extracts, as well as the antifungal and cytotoxicity properties of plumbagin.

Suppressive effect of maslinic acid on PMA-induced protein kinase C in human B-lymphoblastoid cells.

Protein kinase C (PKC) has been implicated in carcinogenesis and displays variable expression profiles during cancer progression. Studies of dietary phytochemicals on cancer signalling pathway regulation have been conducted to search for potent signalling regulatory agents. The present study was designed to evaluate any suppressive effect of maslinic acid on PKC expression in human B-lymphoblastoid cells (Raji cells), and to identify the PKC isoforms expressed. Effects of maslinic acid on PKC activity were determined using a PepTag assay for non-radioactive detection of PKC. The highest expression in Raji cells was obtained at 20 nM PMA induced for 6 hours. Suppressive effects of maslinic acid were compared with those of four PKC inhibitors (H- 7, rottlerin, sphingosine, staurosporine) and two triterpenes (oleanolic acid and ursolic acid). The IC50 values achieved for maslinic acid, staurosporine, H-7, sphingosine, rottlerin, ursolic acid and oleanolic acid were 11.52, 0.011, 0.767, 2.45, 5.46, 27.93 and 39.29 µM, respectively. Four PKC isoforms, PKC ßI, ßII, δ, and ζ, were identified in Raji cells via western blotting. Maslinic acid suppressed the expression of PKC ßI, δ, and ζ in a concentration-dependent manner. These preliminary results suggest promising suppressive effects of maslinic acid on PKC activity in Raji cells. Maslinic acid could be a potent cancer chemopreventive agent that may be involved in regulating many downstream signalling pathways that are activated through PKC receptors.

Synthesis, characterization and biological properties of cobalt(II) complexes of 1,10-phenanthroline and maltol.

The synthesis and characterization of two cobalt(II) complexes, Co(phen)(ma)Cl 1 and Co(ma)(2)(phen) 2, (phen=1,10-phenanthroline, ma(-)=maltolate or 2-methyl-4-oxo-4H-pyran-3-olate) are reported herein. The complexes have been characterized by FTIR, CHN analysis, fluorescence spectroscopy, UV-visible spectroscopy, conductivity measurement and X-ray crystallography. The number of chelated maltolate ligands seems to influence their DNA recognition, topoisomerase I inhibition and antiproliferative properties.

Cancer chemopreventive activity of maslinic acid: suppression of COX-2 expression and inhibition of NF-κB and AP-1 activation in Raji cells.

Chronic inflammation is one of the predisposing factors for neoplastic transformation. Targeting inflammation through suppression of the pro-inflammatory pathway by dietary phytochemicals provides an important strategy for cancer prevention. Maslinic acid is a novel natural triterpenoid known to inhibit proliferation and induce apoptosis in some tumor cell lines. Although maslinic acid has cytotoxic and pro-apoptotic effects on cancer cells, the underlying mechanisms of its effects on the inflammatory pathway have yet to be elucidated. It has been reported that abnormal expression of pro-inflammatory enzyme cyclooxygenase-2 (COX-2) causes promotion of cellular proliferation, suppression of apoptosis, enhancement of angiogenesis and invasiveness. In the present study, the suppressive effect of maslinic acid on COX-2 expression and the binding activity of upstream transcription factors NF- κB and AP-1, which are known to regulate COX-2 transcriptional activation, were assessed using Raji cells. The anti-inflammatory action of maslinic acid was benchmarked against oleanolic acid and other standard drugs. Western blot analysis and electrophoretic mobility shift assay (EMSA) were employed to analyze COX-2 expression as well as NF- κB and AP-1 binding activity. Our results showed that maslinic acid suppresses COX-2 expression in a concentration-dependent manner. Likewise, the constitutive nuclear NF- κB (p65) activity as well as phorbol 12-myristate 13-acetate (PMA)- and sodium N-butyrate (SnB)-induced AP-1 binding activity in Raji cells were significantly reduced following treatment with maslinic acid. Since maslinic acid suppresses COX-2 expression in Raji cells at concentrations that also lowered the NF- κB (p65) and AP-1 binding activity, it is possible that the suppression of COX-2 by this natural triterpenoid might be achieved, at least in part, via the NF- κB and AP-1 signaling pathways.

Evaluation of a nurse-led telephone follow-up clinic for patients with indolent and chronic hematological malignancies: a pilot study.

A physician/nurse collaborative team sought to determine whether a nurse-led telephone clinic (Teleclinic) could effectively and safely be used to follow patients with indolent and chronic hematological malignancies. Patients seen at their routine follow-up visit were assessed for eligibility for the Teleclinic, then referred to the pilot Teleclinic by their oncologist. Patients were interviewed by telephone by an oncology nurse experienced in hematologic malignancies. Fifty-three patients consented to participate in the pilot study. Following their Teleclinic interview, patients were asked to complete a "Subject Satisfaction Questionnaire" (SSQ). Overall patient satisfaction with the Teleclinic was high. It was determined that patients with low-grade and chronic hematological malignancies could be followed effectively and safely by an oncology nurse-led telephone clinic.

Adjuvant therapy with raltitrexed in patients with colorectal cancer intolerant of 5-fluorouracil: British Columbia Cancer Agency experience.

BACKGROUND: Severe 5-FU toxicity in adjuvant therapy of colorectal cancer may require change of therapy. We retrospectively explored the safety and efficacy of adjuvant raltitrexed in patients intolerant of 5-FU. METHODS: Over a 5 year period, patients who received 5-FU and subsequent raltitrexed therapy were identified. RESULTS: There were 44 patients, (39 stage III). Median number of prior 5-FU cycles was 2. Three year relapse free and overall survival proportions for stage III patients were 70.8% and 83.6%, respectively. CONCLUSIONS: Raltitrexed adjuvant therapy can be given safely and effectively in patients where further 5-FU is contraindicated.

Mapping the journey of cancer patients through the health care system. Part 3: An approach to staging.

This is the third in a series of articles relating results from a line of research whose intent was to construct a complete history of patient interactions with the health care system using available data sources for all patients diagnosed in 1990 with a primary breast, colorectal, or lung tumour in Manitoba. This article presents details of the development and application of methods to produce TNM staging data on the roughly 2,000 patients in this population. The operational definitions constructed for this research can be adapted for other tumour sites and data sources. Findings include methods developed to overcome the sometimes ambiguous and inconsistent available documentation, which ultimately produced reliable TNM staging data. Survival data for this population by stage of disease are given.

Mapping the journey of cancer patients through health care system. Part 1: developing the research question.

This is the first in a series of articles relating results from research which constructed a complete history of interactions with the health care system from available data sources for all patients diagnosed in 1990 with primary breast, colorectal, or lung tumours in Manitoba from one year prior to diagnosis through to two years post-diagnosis. This article presents the motivation and genesis for this line of research. The study evolved from the question of "What happens to a person who is diagnosed with cancer?" into a major research endeavour encompassing a broad spectrum of philosophic and clinical research questions. A large interdisciplinary team collaborated on developing operational methods to combine existing data sources into unified cancer patient histories.

Mapping the journey of cancer patients through the health care system. Part 2: Methodological approaches and basic findings.

This is the second in a series of articles from a line of research whose intent was to construct a complete history of interactions with the health care system. This paper provides details of the methods developed to collect and collate the scattered information regarding the event history (trajectory) that a cancer patient experiences in traveling through the Manitoba health care system from one year prior to diagnosis through to two years post-diagnosis. Survival data were obtained through 1994. Basic population data obtained from this work are also presented, including survival information through to four years post-diagnosis. Issues regarding standardized data recording and detail level of clinical events in the chart record are discussed. This part of the research demonstrates that diverse data sources in the health care system can be linked with a high degree of accuracy and completeness of data.