PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (1066252)

Clipboard (0)
None

Related Articles

1.  Induction of apoptosis of endothelial cells by Viscum album: a role for anti-tumoral properties of mistletoe lectins. 
Molecular Medicine  2002;8(10):600-606.
BACKGROUND: Viscum album (VA) preparations consist of aqueous extracts of different types of lectins of VA. Mistletoe lectins have both cytotoxic and immunomodulatory properties that support their study for the development for cancer therapy. However, the mechanisms of the anti- tumoral properties in vivo of mistletoe lectins are not fully understood. Because endothelial cells (EC) play a pivotal role in tumor angiogenesis, we tested the hypothesis that VA extracts induce endothelial cell death and apoptosis. MATERIALS AND METHODS: We investigated the effect of various VA preparations on both human venous endothelial cell (HUVEC) and immortalized human venous endothelial cell line (IVEC) using morphologic assessment of EC, FACScan analysis after propidium iodine and annexin V labeling, and detection of cleavage of poly(A)DP-ribose polymerase (PARP). RESULTS: All tested VA preparations, except Iscador P, were cytotoxic in IVEC. Apoptosis, assessed by morphologic examination, annexin V labeling, and Western blot analysis for PARP cleavage, was involved in HUVEC cell death induced by VA preparations derived from plants that grow on oak trees (VA Qu FrF). CONCLUSIONS: Results from the present study suggest that VA extract-induced endothelial apoptosis may explain the tumor regression associated with the therapeutic use of VA preparations and support further investigations to develop novel anti-angiogenic compounds based on mistletoe compounds.
PMCID: PMC2039938  PMID: 12477970
2.  Interaction of standardized mistletoe (Viscum album) extracts with chemotherapeutic drugs regarding cytostatic and cytotoxic effects in vitro 
Background
Given the importance of complementary and alternative medicine (CAM) to cancer patients, there is an increasing need to learn more about possible interactions between CAM and anticancer drugs. Mistletoe (Viscum album L.) belongs to the medicinal herbs that are used as supportive care during chemotherapy. In the in vitro study presented here the effect of standardized mistletoe preparations on the cytostatic and cytotoxic activity of several common conventional chemotherapeutic drugs was investigated using different cancer cell lines.
Methods
Human breast carcinoma cell lines HCC1937 and HCC1143 were treated with doxorubicin hydrochloride, pancreas adenocarcinoma cell line PA-TU-8902 with gemcitabine hydrochloride, prostate carcinoma cell line DU145 with docetaxel and mitoxantrone hydrochloride and lung carcinoma cell line NCI-H460 was treated with docetaxel and cisplatin. Each dose of the respective chemotherapeutic drug was combined with Viscum album extract (VAE) in clinically relevant concentrations and proliferation and apoptosis were measured.
Results
VAE did not inhibit chemotherapy induced cytostasis and cytotoxicity in any of our experimental settings. At higher concentrations VAE showed an additive inhibitory effect.
Conclusions
Our in vitro results suggest that no risk of safety by herb drug interactions has to be expected from the exposition of cancer cells to chemotherapeutic drugs and VAE simultaneously.
doi:10.1186/1472-6882-14-6
PMCID: PMC3893555  PMID: 24397864
Mistletoe (Viscum album L.); Iscador; Chemotherapy; Drug interactions; Cytostasis; Cytotoxicity
3.  Safety of higher dosages of Viscum album L. in animals and humans - systematic review of immune changes and safety parameters 
Background
Viscum album L extracts (VAE, mistletoe) and isolated mistletoe lectins (ML) have immunostimulating properties and a strong dose-dependent cytotoxic activity. They are frequently used in complementary cancer treatment, mainly to improve quality of life, but partly also to influence tumour growth, especially by injecting VAE locally and in high dosage. The question is raised whether these higher dosages can induce any harm or immunosuppressive effects.
Methods
Systematic review of all experiments and clinical studies investigating higher dosages of VAE in animals and humans (Viscum album > 1 mg in humans corresponding to > 0.02 mg/kg in animals or ML > 1 ng/kg) and assessing immune parameters or infections or adverse drug reactions.
Results
69 clinical studies and 48 animal experiments reported application of higher doses of VAE or ML and had assessed immune changes and/or harm. In these studies, Viscum album was applied in dosages up to 1500 mg in humans and 1400 mg/kg in animals, ML was applied up to 6.4 μg/kg in humans and in animals up to 14 μg/kg subcutaneously, 50 μg/kg nasally and 500 μg/kg orally. A variety of immune parameters showed fluctuating or rising outcomes, but no immunosuppressive effect. Side effects consisted mainly of dose-dependent flu-like symptoms (FLS), fever, local reactions at the injection site and various mild unspecific effects. Occasionally, allergic reactions were reported. After application of high doses of recombinant ML, reversible hepatotoxicity was observed in some cases.
Conclusions
Application of higher dosages of VAE or ML is not accompanied by immunosuppression; altogether VAE seems to exhibit low risk but should be monitored by clinicians when applied in high dosages.
doi:10.1186/1472-6882-11-72
PMCID: PMC3180269  PMID: 21871125
4.  Fermented Mistletoe Extract as a Multimodal Antitumoral Agent in Gliomas 
In Europe, commercially available extracts from the white-berry mistletoe (Viscum album L.) are widely used as a complementary cancer therapy. Mistletoe lectins have been identified as main active components and exhibit cytotoxic effects as well as immunomodulatory activity. Since it is still not elucidated in detail how mistle toe extracts such as ISCADOR communicate their effects, we analyzed the mechanisms that might be responsible for their antitumoral function on a molecular and functional level. ISCADOR-treated glioblastoma (GBM) cells down-regulate central genes involved in glioblastoma progression and malignancy such as the cytokine TGF-β and matrix-metalloproteinases. Using in vitro glioblastoma/immune cell co-cultivation assays as well as measurement of cell migration and invasion, we could demonstrate that in glioblastoma cells, lectin-rich ISCADOR M and ISCADOR Q significantly enforce NK-cell-mediated GBM cell lysis. Beside its immune stimulatory effect, ISCADOR reduces the migratory and invasive potential of glioblastoma cells. In a syngeneic as well as in a xenograft glioblastoma mouse model, both pretreatment of tumor cells and intratumoral therapy of subcutaneously growing glioblastoma cells with ISCADOR Q showed delayed tumor growth. In conclusion, ISCADOR Q, showing multiple positive effects in the treatment of glioblastoma, may be a candidate for concomitant treatment of this cancer.
doi:10.1155/2012/501796
PMCID: PMC3485514  PMID: 23133496
5.  Identification and characterization of a nontypeable Haemophilus influenzae putative toxin-antitoxin locus 
BMC Microbiology  2004;4:30.
Background
Certain strains of an obligate parasite of the human upper respiratory tract, nontypeable Haemophilus influenzae (NTHi), can cause invasive diseases such as septicemia and meningitis, as well as chronic mucosal infections such as otitis media. To do this, the organism must invade and survive within both epithelial and endothelial cells. We have identified a facilitator of NTHi survival inside human cells, virulence-associated protein D (vapDHi, encoded by gene HI0450). Both vapDHi and a flanking gene, HI0451, exhibit the genetic and physical characteristics of a toxin/antitoxin (TA) locus, with VapDHi serving as the toxin moiety and HI0451 as the antitoxin. We propose the name VapXHi for the HI0451 antitoxin protein. Originally identified on plasmids, TA loci have been found on the chromosomes of a number of bacterial pathogens, and have been implicated in the control of translation during stressful conditions. Translation arrest would enhance survival within human cells and facilitate persistent or chronic mucosal infections.
Results
Isogenic mutants in vapDHi were attenuated for survival inside human respiratory epithelial cells (NCI-H292) and human brain microvascular endothelial cells (HBMEC), the in vitro models of mucosal infection and the blood-brain barrier, respectively. Transcomplementation with a vapDHi allele restored wild-type NTHi survival within both cell lines. A PCR survey of 59 H. influenzae strains isolated from various anatomical sites determined the presence of a vapDHiallele in 100% of strains. Two isoforms of the gene were identified in this population; one that was 91 residues in length, and another that was truncated to 45 amino acids due to an in-frame deletion. The truncated allele failed to transcomplement the NTHi vapDHi survival defect in HBMEC. Subunits of full-length VapDHi homodimerized, but subunits of the truncated protein did not. However, truncated protein subunits did interact with full-length subunits, and this interaction resulted in a dominant-negative phenotype. Although Escherichia coli does not contain a homologue of either vapDHi or vapXHi, overexpression of the VapDHi toxin in trans resulted in E. coli cell growth arrest. This arrest could be rescued by providing the VapXHi antitoxin on a compatible plasmid.
Conclusion
We conclude that vapDHi and vapXHi may constitute a H. influenzae TA locus that functions to enhance NTHi survival within human epithelial and endothelial cells.
doi:10.1186/1471-2180-4-30
PMCID: PMC503385  PMID: 15274747
6.  Difficulties and Perspectives of Immunomodulatory Therapy with Mistletoe Lectins and Standardized Mistletoe Extracts in Evidence-Based Medicine 
Viscum album preparations are aqueous mistletoe plant extracts used in complementary and alternative medicine as immunomodulators in cancer therapy. However, evidence of immunological efficacy of mistletoe extracts (MEs) used in clinical trials is often lacking. Mechanisms involved in anti-tumor properties of ME and mistletoe lectins (MLs) modify both innate and adaptive immune systems, according to animal model experiments. In the background of these effects, a selective binding of ML on CD75 ganglioside receptors of interleukin 12 (IL-12)-producing macrophages or dendritic cells can play an important role. Immunological effects of ME correlate with their lectin activity, showing a bell-shaped dose-response curve of efficacy. Therefore, a correct determination of MLs for the standardization of commercial ME is essential. However, plant MLs exhibit heterogeneity, which most likely results from post-translational processing. In addition, amino acid analysis of ML has revealed numerous conservative substitutions along their amino acid sequence. Consequently, ML research needs new perspectives, and the advantages and disadvantages of purified and biologically better defined ML preparations are also discussed in this article.
doi:10.1093/ecam/nep191
PMCID: PMC3135167  PMID: 19939951
7.  Triterpenoids Amplify Anti-Tumoral Effects of Mistletoe Extracts on Murine B16.F10 Melanoma In Vivo 
PLoS ONE  2013;8(4):e62168.
Purpose
Mistletoe extracts are often used in complementary cancer therapy although the efficacy of that therapy is controversially discussed. Approved mistletoe extracts contain mainly water soluble compounds of the mistletoe plant, i.e. mistletoe lectins. However, mistletoe also contains water-insoluble triterpenoids (mainly oleanolic acid) that have anti-tumorigenic effects. To overcome their loss in watery extracts we have solubilized mistletoe triterpenoids with cyclodextrins, thus making them available for in vivo cancer experiments.
Experimental design
B16.F10 subcutaneous melanoma bearing C57BL/6 mice were treated with new mistletoe extracts containing both water soluble compounds and solubilized triterpenoids. Tumor growth and survival was monitored. In addition, histological examinations of the tumor material and tumor surrounding tissue were performed.
Results
Addition of solubilized triterpenoids increased the anti-tumor effects of the mistletoe extracts, resulting in reduced tumor growth and prolonged survival of the mice. Histological examination of the treated tumors showed mainly tumor necrosis and some apoptotic cells with active caspase-3 and TUNEL staining. A significant decrease of CD31-positive tumor blood vessels was observed after treatment with solubilized triterpenoids and different mistletoe extracts.
Conclusion
We conclude that the addition of solubilized mistletoe triterpenoids to conventional mistletoe extracts improves the efficacy of mistletoe treatment and may represent a novel treatment option for malignant melanoma.
doi:10.1371/journal.pone.0062168
PMCID: PMC3629099  PMID: 23614029
8.  Evaluation of Preclinical Assays to Investigate an Anthroposophic Pharmaceutical Process Applied to Mistletoe (Viscum album L.) Extracts 
Extracts from European mistletoe (Viscum album L.) developed in anthroposophic medicine are based on specific pharmaceutical procedures to enhance remedy efficacy. One such anthroposophic pharmaceutical process was evaluated regarding effects on cancer cell toxicity in vitro and on colchicine tumor formation in Lepidium sativum. Anthroposophically processed Viscum album extract (APVAE) was produced by mixing winter and summer mistletoe extracts in the edge of a high-speed rotating disk and was compared with manually mixed Viscum album extract (VAE). The antiproliferative effect of VAE/APVAE was determined in five cell lines (NCI-H460, DU-145, HCC1143, MV3, and PA-TU-8902) by WST-1 assay in vitro; no difference was found between VAE and APVAE in any cell line tested (P > 0.14). Incidence of colchicine tumor formation was assessed by measurement of the root/shoot-ratio of seedlings of Lepidium sativum treated with colchicine as well as VAE, APVAE, or water. Colchicine tumor formation decreased after application of VAE (−5.4% compared to water, P < 0.001) and was even stronger by APVAE (−8.8% compared to water, P < 0.001). The high-speed mistletoe extract mixing process investigated thus did not influence toxicity against cancer cells but seemed to sustain morphostasis and to enhance resistance against external noxious influences leading to phenomenological malformations.
doi:10.1155/2014/620974
PMCID: PMC4024402  PMID: 24876872
9.  NCCAM/NCI Phase 1 Study of Mistletoe Extract and Gemcitabine in Patients with Advanced Solid Tumors 
Purpose. European Mistletoe (Viscum album L.) extracts (mistletoe) are commonly used for cancer treatment in Europe. This phase I study of gemcitabine (GEM) and mistletoe in advanced solid cancers (ASC) evaluated: (1) safety, toxicity, and maximum tolerated dose (MTD), (2) absolute neutrophil count (ANC) recovery, (3) formation of mistletoe lectin antibodies (ML ab), (4) cytokine plasma concentrations, (5) clinical response, and (6) pharmacokinetics of GEM. Methods. Design: increasing mistletoe and fixed GEM dose in stage I and increasing doses of GEM with a fixed dose of mistletoe in stage II. Dose limiting toxicities (DLT) were grade (G) 3 nonhematologic and G4 hematologic events; MTD was reached with 2 DLTs in one dosage level. Response in stage IV ASC was assessed with descriptive statistics. Statistical analyses examined clinical response/survival and ANC recovery. Results. DLTs were G4 neutropenia, G4 thrombocytopenia, G4 acute renal failure, and G3 cellulitis, attributed to mistletoe. GEM 1380 mg/m2 and mistletoe 250 mg combined were the MTD. Of 44 patients, 24 developed nonneutropenic fever and flu-like syndrome. GEM pharmacokinetics were unaffected by mistletoe. All patients developed ML3 IgG antibodies. ANC showed a trend to increase between baseline and cycle 2 in stage I dose escalation. 6% of patients showed partial response, 42% stable disease. Median survival was 200 days. Compliance with mistletoe injections was high. Conclusion. GEM plus mistletoe is well tolerated. No botanical/drug interactions were observed. Clinical response is similar to GEM alone.
doi:10.1155/2013/964592
PMCID: PMC3826324  PMID: 24285980
10.  VapC Toxins from Mycobacterium tuberculosis Are Ribonucleases that Differentially Inhibit Growth and Are Neutralized by Cognate VapB Antitoxins 
PLoS ONE  2011;6(6):e21738.
The chromosome of Mycobacterium tuberculosis (Mtb) encodes forty seven toxin-antitoxin modules belonging to the VapBC family. The role of these modules in the physiology of Mtb and the function(s) served by their expansion are unknown. We investigated ten vapBC modules from Mtb and the single vapBC from M. smegmatis. Of the Mtb vapCs assessed, only Rv0549c, Rv0595c, Rv2549c and Rv2829c were toxic when expressed from a tetracycline-regulated promoter in M. smegmatis. The same genes displayed toxicity when conditionally expressed in Mtb. Toxicity of Rv2549c in M. smegmatis correlated with the level of protein expressed, suggesting that the VapC level must exceed a threshold for toxicity to be observed. In addition, the level of Rv2456 protein induced in M. smegmatis was markedly lower than Rv2549c, which may account for the lack of toxicity of this and other VapCs scored as ‘non-toxic’. The growth inhibitory effects of toxic VapCs were neutralized by expression of the cognate VapB as part of a vapBC operon or from a different chromosomal locus, while that of non-cognate antitoxins did not. These results demonstrated a specificity of interaction between VapCs and their cognate VapBs, a finding corroborated by yeast two-hybrid analyses. Deletion of selected vapC or vapBC genes did not affect mycobacterial growth in vitro, but rendered the organisms more susceptible to growth inhibition following toxic VapC expression. However, toxicity of ‘non-toxic’ VapCs was not unveiled in deletion mutant strains, even when the mutation eliminated the corresponding cognate VapB, presumably due to insufficient levels of VapC protein. Together with the ribonuclease (RNase) activity demonstrated for Rv0065 and Rv0617 – VapC proteins with similarity to Rv0549c and Rv3320c, respectively – these results suggest that the VapBC family potentially provides an abundant source of RNase activity in Mtb, which may profoundly impact the physiology of the organism.
doi:10.1371/journal.pone.0021738
PMCID: PMC3126847  PMID: 21738782
11.  Protein Fractions from Korean Mistletoe (Viscum Album coloratum) Extract Induce Insulin Secretion from Pancreatic Beta Cells 
Mistletoe (Viscum Album coloratum) has been known as a medicinal plant in European and Asian countries. Recent data show that biological activity of mistletoe alleviates hypertension, heart disease, renal failure, and cancer development. In this study, we report the antidiabetic effect of Korean mistletoe extract (KME). KME treatments enhanced the insulin secretion from the pancreatic β-cell without any effects of cytotoxicity. PDX-1 and beta2/neuroD known as transcription factors that regulate the expression of insulin gene were upregulated by treatment of the KME protein fractions isolated by ion-exchange chromatography after ammonium sulfate precipitation. Furthermore, these KME protein fractions significantly lowered the blood glucose level and the volume of drinking water in alloxan induced hyperglycemic mice. Taken together with the findings, it provides new insight that KME might be served as a useful source for the development of medicinal reagent to reduce blood glucose level of type I diabetic patients.
doi:10.1155/2014/703624
PMCID: PMC4053293  PMID: 24959189
12.  Functional Modulation of Vascular Adhesion Protein-1 by a Novel Splice Variant 
PLoS ONE  2013;8(1):e54151.
Vascular Adhesion Protein-1 (VAP-1) is an endothelial adhesion molecule belonging to the primary amine oxidases. Upon inflammation it takes part in the leukocyte extravasation cascade facilitating transmigration of leukocytes into the inflamed tissue. Screening of a human lung cDNA library revealed the presence of an alternatively spliced shorter transcript of VAP-1, VAP-1Δ3. Here, we have studied the functional and structural characteristics of VAP-1Δ3, and show that the mRNA for this splice variant is expressed in most human tissues studied. In comparison to the parent molecule this carboxy-terminally truncated isoform lacks several of the amino acids important in the formation of the enzymatic groove of VAP-1. In addition, the conserved His684, which takes part in coordinating the active site copper, is missing from VAP-1Δ3. Assays using the prototypic amine substrates methylamine and benzylamine demonstrated that VAP-1Δ3 is indeed devoid of the semicarbazide-sensitive amine oxidase (SSAO) activity characteristic to VAP-1. When VAP-1Δ3-cDNA is transfected into cells stably expressing VAP-1, the surface expression of the full-length molecule is reduced. Furthermore, the SSAO activity of the co-transfectants is diminished in comparison to transfectants expressing only VAP-1. The observed down-regulation of both the expression and enzymatic activity of VAP-1 may result from a dominant-negative effect caused by heterodimerization between VAP-1 and VAP-1Δ3, which was detected in co-immunoprecipitation studies. This alternatively spliced transcript adds thus to the repertoire of potential regulatory mechanisms through which the cell-surface expression and enzymatic activity of VAP-1 can be modulated.
doi:10.1371/journal.pone.0054151
PMCID: PMC3548902  PMID: 23349812
13.  Preclinical and Clinical Effects of Mistletoe against Breast Cancer 
BioMed Research International  2014;2014:785479.
Breast cancer is among the most frequent types of cancer in women worldwide. Current conventional treatment options are accompanied by side effects. Mistletoe is amongst the important herbal medicines traditionally used as complementary remedies. An increasing number of studies have reported anticancer activity of mistletoe extracts on breast cancer cells and animal models. Some recent evidence suggests that cytotoxic activity of mistletoe may be mediated through different mechanisms. These findings provide a good base for clinical trials. Various studies on mistletoe therapy for breast cancer patients revealed similar findings concerning possible benefits on survival time, health-related quality of life (HRQoL), remission rate, and alleviating adverse reactions to conventional therapy. This review provides an overview of the recent findings on preclinical experiments and clinical trials of mistletoe for its cytotoxic and antitumor activity and its effect on HRQoL in breast cancer patients. Moreover, studies investigating molecular and cellular mechanisms underlying antitumor activity of mistletoe are discussed in this paper. The analyzed trials provided evidence that there might be a combination of pharmacological and motivational aspects mediated by the mistletoe extract application which may contribute to the clinical benefit and positive outcome such as improved HRQoL and self-regulation in breast cancer patients.
doi:10.1155/2014/785479
PMCID: PMC4127267  PMID: 25136622
14.  Mistletoe preparation (Viscum Fraxini-2) as palliative treatment for malignant pleural effusion: a feasibility study with comparison to bleomycin 
ecancermedicalscience  2014;8:424.
Background
Malignant pleural effusion is a common problem in patients with solid tumours. It has a significant impact on quality of life, and, hence, there is a substantial need to investigate new agents to treat it.
Patients and methods
This is a prospective randomised controlled study, including patients with symptomatic recurrent malignant pleural effusion of different primaries. Patients were randomised into two groups: the first group received five ampoules of mistletoe preparation with defined lectin content (Viscum Fraxini-2, ATOS Pharma) diluted in 10 cc glucose 5% solution. Re-instillation was repeated every week until complete dryness of the pleural fluid was achieved (the maximum duration of the therapy was eight weeks). The second group received 60 units of bleomycin once intrapleurally.
Aims
The primary aim of this paper was to evaluate the efficacy of mistletoe preparation as a palliative treatment for malignant pleural effusions in comparison with bleomycin. The secondary aim was to evaluate the tolerability of the mistletoe preparation.
Results
A total of 23 patients were included and followed up during the study from December 2007 to January 2012: 13 patients received mistletoe preparation, and ten patients received bleomycin. Overall clinical response was reported in 61.5% of the mistletoe preparation arm versus 30% in bleomycin arm (p = 0.2138), 95% CI = (–0.1203, 0.6325). The toxicity of both arms was mild and manageable; the mistletoe preparation arm included fever, chills, headache, malaise, and, in two cases, allergic reaction, which was controlled by discontinuation of the drug and steroid injection.
Conclusion
Mistletoe preparation is an efficient and well tolerated sclerosant agent which needs further investigation.
doi:10.3332/ecancer.2014.424
PMCID: PMC4004388  PMID: 24834119
mistletoe preparation; pleural effusion
15.  Assessment of Shape Changes of Mistletoe Berries: A New Software Approach to Automatize the Parameterization of Path Curve Shaped Contours 
PLoS ONE  2013;8(4):e60522.
Photographs of mistletoe (Viscum album L.) berries taken by a permanently fixed camera during their development in autumn were subjected to an outline shape analysis by fitting path curves using a mathematical algorithm from projective geometry. During growth and maturation processes the shape of mistletoe berries can be described by a set of such path curves, making it possible to extract changes of shape using one parameter called Lambda. Lambda describes the outline shape of a path curve. Here we present methods and software to capture and measure these changes of form over time. The present paper describes the software used to automatize a number of tasks including contour recognition, optimization of fitting the contour via hill-climbing, derivation of the path curves, computation of Lambda and blinding the pictures for the operator. The validity of the program is demonstrated by results from three independent measurements showing circadian rhythm in mistletoe berries. The program is available as open source and will be applied in a project to analyze the chronobiology of shape in mistletoe berries and the buds of their host trees.
doi:10.1371/journal.pone.0060522
PMCID: PMC3614953  PMID: 23565255
16.  Transcriptional and Proteolytic Regulation of the Toxin-Antitoxin Locus vapBC10 (ssr2962/slr1767) on the Chromosome of Synechocystis sp. PCC 6803 
PLoS ONE  2013;8(11):e80716.
VapBC toxin-antitoxin (TA) systems are defined by the association of a PIN-domain toxin with a DNA-binding antitoxin, and are thought to play important physiological roles in bacteria and archaea. Recently, the PIN-associated gene pair PIN-COG2442 was proposed to encode VapBC-family TA system and found to be abundant in cyanobacteria. However, the features of these predicted TA loci remain under investigation. We here report characterization of the PIN-COG2442 locus vapBC10 (ssr2962/slr1767) on the chromosome of Synechocystis sp. PCC 6803. RT-PCR analysis revealed that the vapBC10 genes were co-transcribed under normal growth conditions. Ectopic expression of the PIN-domain protein VapC10 caused growth arrest of Escherichia coli that does not possess vapBC TA locus. Coincidentally, this growth-inhibition effect could be neutralized by either simultaneous or subsequent production of the COG2442-domain protein VapB10 through formation of the TA complex VapBC10 in vivo. In contrast to the transcription repression activity of the well-studied antitoxins, VapB10 positively auto-regulated the transcription of its own operon via specific binding to the promoter region. Furthermore, in vivo experiments in E. coli demonstrated that the Synechocystis protease ClpXP2s, rather than Lons, could cleave VapB10 and proteolytically activate the VapC10 toxicity. Our results show that the PIN-COG2442 locus vapBC10 encodes a functional VapBC TA system with an alternative mechanism for the transcriptional auto-regulation of its own operon.
doi:10.1371/journal.pone.0080716
PMCID: PMC3834315  PMID: 24260461
17.  Effect of gamma irradiation on mistletoe (Viscum album) lectin-mediated toxicity and immunomodulatory activity☆ 
FEBS Open Bio  2013;3:106-111.
This study evaluated the effect of gamma irradiation on the reduction of the toxicity of mistletoe lectin using both in vitro and in vivo models. To extract the lectin from mistletoe, an (NH4)2SO4 precipitation method was employed and the precipitant purified using a Sepharose 4B column to obtain the pure lectin fraction. Purified lectin was then gamma-irradiated at doses of 0, 5, 10, 15, and 20 kGy, or heated at 100 °C for 30 min. Toxic effects of non-irradiated, irradiated, and heat-treated lectins were tested using hemagglutination assays, cytotoxicity assays, hepatotoxicity, and a mouse survival test and immunological response was tested using cytokine production activity. Hemagglutination of lectin was remarkably decreased (P < 0.05) by irradiation at doses exceeding 10 kGy and with heat treatment. However, lectin irradiated with 5 kGy maintained its hemagglutination activity. The cytotoxicity of lectin was decreased by irradiation at doses over 5 kGy and with heat treatment. In experiments using mouse model, glutamate oxaloacetate transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels were decreased in the group treated with the 5 kGy irradiated and heat-treated lectins as compared to the intact lectin, and it was also shown that 5 kGy irradiated and heat-treated lectins did not cause damage in liver tissue or mortality. In the result of immunological response, tumor necrosis factor (TNF-α) and interleukin (IL-6) levels were significantly (P < 0.05) increased in the 5 kGy gamma-irradiated lectin treated group. These results indicate that 5 kGy irradiated lectin still maintained the immunological response with reduction of toxicity. Therefore, gamma-irradiation may be an effective method for reducing the toxicity of lectin maintaining the immune response.
Highlights
▸ Cytotoxicity of lectin against immune cells was decreased by gamma-irradiation at doses above 5 kGy. ▸ The liver toxicity of gamma-irradiated lectin (5 kGy) was decreased, as shown by levels of GOT and GPT. ▸ Gamma-irradiated lectin (5 kGy) was not lethal for mice. ▸ Gamma-irradiated lectin (5 kGy) still maintained immunological responses.
doi:10.1016/j.fob.2013.01.003
PMCID: PMC3668527  PMID: 23847758
Mistletoe lectin; Toxicity; Gamma irradiation; Immune response; Cytotoxicity; Cytokine
18.  Viscum album L. extracts in breast and gynaecological cancers: a systematic review of clinical and preclinical research 
Background
Viscum album L. extracts (VAE, European mistletoe) are a widely used medicinal plant extract in gynaecological and breast-cancer treatment.
Methods
Systematic review to evaluate clinical studies and preclinical research on the therapeutic effectiveness and biological effects of VAE on gynaecological and breast cancer. Search of databases, reference lists and expert consultations. Criteria-based assessment of methodological study quality.
Results
19 randomized (RCT), 16 non-randomized (non-RCT) controlled studies, and 11 single-arm cohort studies were identified that investigated VAE treatment of breast or gynaecological cancer. They included 2420, 6399 and 1130 patients respectively. 8 RCTs and 8 non-RCTs were embedded in the same large epidemiological cohort study. 9 RCTs and 13 non-RCTs assessed survival; 12 reported a statistically significant benefit, the others either a trend or no difference. 3 RCTs and 6 non-RCTs assessed tumour behaviour (remission or time to relapse); 3 reported statistically significant benefit, the others either a trend, no difference or mixed results. Quality of life (QoL) and tolerability of chemotherapy, radiotherapy or surgery was assessed in 15 RCTs and 9 non-RCTs. 21 reported a statistically significant positive result, the others either a trend, no difference, or mixed results. Methodological quality of the studies differed substantially; some had major limitations, especially RCTs on survival and tumour behaviour had very small sample sizes. Some recent studies, however, especially on QoL were reasonably well conducted. Single-arm cohort studies investigated tumour behaviour, QoL, pharmacokinetics and safety of VAE. Tumour remission was observed after high dosage and local application. VAE application was well tolerated. 34 animal experiments investigated VAE and isolated or recombinant compounds in various breast and gynaecological cancer models in mice and rats. VAE showed increase of survival and tumour remission especially in mice, while application in rats as well as application of VAE compounds had mixed results. In vitro VAE and its compounds have strong cytotoxic effects on cancer cells.
Conclusion
VAE shows some positive effects in breast and gynaecological cancer. More research into clinical efficacy is warranted.
doi:10.1186/1756-9966-28-79
PMCID: PMC2711058  PMID: 19519890
19.  Induction and function of vascular adhesion protein-1 at sites of inflammation 
The Journal of Experimental Medicine  1993;178(6):2255-2260.
Emigration of leukocytes from the blood into the tissues is critical in controlling lymphocyte patrolling in different lymphatic organs and in leukocyte accumulation at sites of inflammation. During the first stage of the extravasation process, leukocytes bind to the endothelial lining of vessels. At the molecular level, several adhesion molecules on leukocytes and endothelial cells function as receptor-ligand pairs in mediating this dynamic interaction. Recently, we have identified a novel human endothelial cell molecule, vascular adhesion protein 1 (VAP- 1), that mediates lymphocyte binding (Salmi, M., and S. Jalkanen. 1992. Science [Wash. DC] 257:1407). VAP-1 was initially characterized by mAb 1B2 which inhibits lymphocyte adhesion to high endothelial venules (HEV) and to purified VAP-1 protein. Here we report the location and function of VAP-1 in normal and inflamed tissues in humans. VAP-1 is abundant in HEV of lymphatic organs belonging to the peripheral lymph node system, but considerably less is expressed in vessels of mucosa- associated lymphatic tissues. A subset of venules in most normal nonlymphatic tissues like skin, brain, kidney, liver, and heart is also VAP-1 positive. In addition to vessels, VAP-1 is distributed on a few other cell types, most notably in dendritic-like cells of germinal centers. At sites of inflammation, such as in inflammatory bowel diseases and chronic dermatoses, expression of VAP-1 is clearly increased. The induced VAP-1 is functional, since mAb 1B2 inhibits lymphocyte binding to inflamed lamina propria venules by approximately 60%. Thus VAP-1 is an endothelial adhesion molecule that under normal conditions is expressed mainly in HEV of lymphatic tissues. However, expression of functional VAP-1 in vivo is upregulated during an inflammatory reaction at other sites as well. Inducibility of VAP-1 suggests that it may play a significant role, not only in recirculation of lymphocytes, but also in controlling entry of leukocytes into sites of inflammation.
PMCID: PMC2191278  PMID: 8245796
20.  The Effect of a Nurse-Led Multidisciplinary Team on Ventilator-Associated Pneumonia Rates 
Background. Ventilator-associated pneumonia (VAP) is a worrisome, yet potentially preventable threat in critically ill patients. Evidence-based clinical practices targeting the prevention of VAP have proven effective, but the most optimal methods to ensure consistent implementation and compliance remain unknown. Methods. A retrospective study of the trend in VAP rates in a community-hospital's open medical intensive care unit (MICU) after the enactment of a nurse-led VAP prevention team. The period of the study was between April 1, 2009, and September 30, 2012. The team rounded on mechanically ventilated patients every Tuesday and Thursday. They ensured adherence to the evidence-based VAP prevention. A separate and independent infection control team monitored VAP rates. Results. Across the study period, mean VAP rate was 3.20/1000 ventilator days ±5.71 SD. Throughout the study time frame, there was an average monthly reduction in VAP rate of 0.27/1000 ventilator days, P < 0.001 (CI: −0.40–−0.13). Conclusion. A nurse-led interdisciplinary team dedicated to VAP prevention rounding twice a week to ensure adherence with a VAP prevention bundle lowered VAP rates in a community-hospital open MICU. The team had interdepartmental and administrative support and addressed any deficiencies in the VAP prevention bundle components actively.
doi:10.1155/2014/682621
PMCID: PMC4100357  PMID: 25061525
21.  Toxins VapC and PasB from Prokaryotic TA Modules Remain Active in Mammalian Cancer Cells 
Toxins  2014;6(10):2948-2961.
Among the great number of addictive modules which have been discovered, only a few have been characterized. However, research concerning the adoption of toxins from these systems shows their great potential as a tool for molecular biology and medicine. In our study, we tested two different toxins derived from class II addictive modules, pasAB from plasmid pTF-FC2 (Thiobacillus ferrooxidans) and vapBC 2829Rv (Mycobacterium tuberculosis), in terms of their usefulness as growth inhibitors of human cancer cell lines, namely KYSE 30, MCF-7 and HCT 116. Transfection of the pasB and vapC genes into the cells was conducted with the use of two different expression systems. Cellular effects, such as apoptosis, necrosis and changes in the cell cycle, were tested by applying flow cytometry with immunofluorescence staining. Our findings demonstrated that toxins VapC and PasB demonstrate proapoptotic activity in the human cancer cells, regardless of the expression system used. As for the toxin PasB, observed changes were more subtle than for the VapC. The level of expression for both the genes was monitored by QPCR and did not reveal statistically significant differences within the same cell line.
doi:10.3390/toxins6102948
PMCID: PMC4210878  PMID: 25271785
toxin-antitoxin; cancer cells; immunotoxin; VapC; PasB
22.  Safety of Intravenous Application of Mistletoe (Viscum album L.) Preparations in Oncology: An Observational Study 
Background. Traditional mistletoe therapy in cancer patients involves subcutaneous applications of Viscum album L. preparations, with doses slowly increasing based on patient responses. Intravenous infusion of high doses may improve therapeutic outcomes and is becoming more common. Little is known about the safety of this “off-label” application of mistletoe. Methods. An observational study was performed within the Network Oncology. Treatment with intravenous mistletoe applications is described. The frequency of adverse drug reactions (ADRs) to intravenous mistletoe applications was calculated and compared to ADR data from a study on subcutaneous applications. Results. Of 475 cancer patients who received intravenous infusions of Helixor, Abnoba viscum, or Iscador mistletoe preparations, 22 patients (4.6%) reported 32 ADRs of mild (59.4%) or moderate severity (40.6%). No serious ADRs occurred. ADRs were more frequently reported to i.v. mistletoe administered alone (4.3%), versus prior to chemotherapy (1.6%). ADR frequency differed with respect to preparation type, with Iscador preparations showing a higher relative frequency, compared to Abnoba viscum and Helixor. Overall, patients were almost two times less likely to experience an ADR to intravenous compared to subcutaneous application of mistletoe. Conclusion. Intravenous mistletoe therapy was found to be safe and prospective studies for efficacy are recommended.
doi:10.1155/2014/236310
PMCID: PMC4052504  PMID: 24955100
23.  Safety and effects of two mistletoe preparations on production of Interleukin-6 and other immune parameters - a placebo controlled clinical trial in healthy subjects 
Background
In Germany, Iscucin® Populi (IP), a preparation from mistletoe growing on the poplar tree, is used in cancer therapy while Viscum Mali e planta tota (VM), a preparation from mistletoe growing on the apple tree, is used in patients with osteoarthritis. Since mistletoe preparations are suspected to induce production of potentially tumor promoting cytokines like interleukin (IL)-6, further studies on the immunological effects are of interest.
Methods
In this 3-armed randomized, double blind clinical trial healthy volunteers received increasing doses of either IP (strength F, 0.0125%, G, 0.25% and H, 5%, each for 4 weeks), or VM (1:1000 [D3], 1:100 [D2] and 2% each for 4 weeks) or placebo (isotonic solution) subcutaneously twice per week over a period of 12 weeks. Physical examination was performed weekly. Routine laboratory parameters and immunological parameters (C-reactive protein (CRP), differential blood count, lymphocyte subsets, immunoglobulins, IL-6 and tumor necrosis factor (TNF)-α) were analysed every 4 weeks.
Results
71 subjects were included in the study (IP = 30, VM = 21, placebo = 20) of whom 69 concluded it according to protocol. Application of IP strengths G and H caused strong local reactions at the site of injection. In parallel, a distinct eosinophilia (p < 0.001 compared to placebo) occurred. Furthermore, application of all IP concentrations resulted in an increase of CD4 cell counts (p < 0.05) compared to placebo. Stimulation of IL-6 production, CRP or relevant deviations in other laboratory parameters were not observed. Because of local reactions, IP strengths G and H were considered less tolerable than placebo. VM 2% was slightly less tolerable than placebo, caused only mild local reactions and an only small increase in eosinophile counts.
Conclusion
Treatment with IP results in eosinophilia and an increase of CD4 cells but not in an increase of IL-6 or CRP. No safety concerns regarding the two mistletoe preparations have been raised by this study. EudraCT-Number 2007-002166-35.
Trial registration
ClinicalTrials.gov: NCT01378702
doi:10.1186/1472-6882-11-116
PMCID: PMC3257204  PMID: 22114899
24.  Molecular characterization of a lipid-modified virulence-associated protein of Rhodococcus equi and its potential in protective immunity. 
Virulent strains of Rhodococcus equi produce plasmid-mediated 15- and 17-kDa proteins, which are thermoregulated and apparently surface-expressed. We demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) that R. equi produce three antigenically-related virulence-associated proteins, a diffuse 18-22-kDa, a 17.5-kDa and a 15-kDa protein. Phase partitioning of whole cells of R. equi strain 103 with Triton X-114 (TX-114) and labelling with [3H]-labelled palmitic acid showed that the two higher molecular weight proteins are hydrophobic and lipid modified. The 15-kDa protein did not partition into TX-114 and was not lipid modified. Cloning and expression of a fragment of the R. equi virulence plasmid in Escherichia coli showed that the three proteins were expressed from a single gene. Sequence analysis of this gene (designated vapA) revealed a 570-bp open reading frame encoding a polypeptide of 189 amino acids with a calculated molecular mass of 19,175 Da. The mature, nonlipid modified protein had a calculated mass of 16,246 Da. The 17.5- and 18-22-kDa forms of the protein are therefore due to lipid modification. No significant sequence homology of the vapA gene with other reported nucleotide sequences were found. Opsonization of virulent R. equi with an IgG1 mouse monoclonal antibody (MAb103) to the VapA protein significantly enhanced uptake in the murine macrophage cell line IC-21. Intraperitoneal injection of mice with Mab103 enhanced initial clearance from the liver of mice challenged intravenously with R. equi. Immunization of mice with the lipid-modified VapA purified by SDS-PAGE fractionation or with acetone precipitated VapA protein following TX-114 extraction resulted in significantly enhanced clearance from the liver and spleen following intravenous challenge. The VapA protein of R. equi appears therefore to be a protective immunogen.
Images
PMCID: PMC1263734  PMID: 7704843
25.  Impact of the ventilator bundle on ventilator-associated pneumonia in intensive care unit 
Objectives
The ventilator bundle is being promoted to prevent adverse events in ventilated patients including ventilator-associated pneumonia (VAP). We aimed to: (i) examine adoption of the ventilator bundle elements; (ii) determine effectiveness of individual elements and setting characteristics in reducing VAP; (iii) determine effectiveness of two infection-specific elements on reducing VAP; and, (iv) assess crossover effects of complying with VAP elements on central line-associated bloodstream infections.
Design
Cross-sectional survey.
Setting
Four hundred and fifteen ICUs from 250 US hospitals.
Participants
Managers/directors of infection prevention and control departments.
Interventions
Adoption and compliance with ventilator bundle elements.
Main Outcome Measures
VAP rates.
Results
The mean VAP rate was 2.7/1000 ventilator days. Two-thirds (n = 284) reported presence of the full ventilator bundle policy. However, only 66% (n = 188/284) monitored implementation; of those, 39% (n = 73/188) reported high compliance. Only when an intensive care unit (ICU) had a policy, monitored compliance and achieved high compliance were VAP rates lower. Compliance with individual elements or just one of two infection-related element had no impact on VAP (β = −0.79, P= 0.15). There was an association between complying with two infection elements and lower rates (β = −1.81, P< 0.01). There were no crossover effects. Presence of a full-time hospital epidemiologist (HE) was significantly associated with lower VAP rates (β = −3.62, P< 0.01).
Conclusions
The ventilator bundle was frequently present but not well implemented. Individual elements did not appear effective; strict compliance with infection elements was needed. Efforts to prevent VAP may be successful in settings of high levels of compliance with all infection-specific elements and in settings with full-time HEs.
doi:10.1093/intqhc/mzr049
PMCID: PMC3168266  PMID: 21821603
ventilator-associated pneumonia; healthcare-associated infections; infection control; ventilator bundle; intensive care units; quality improvement; guidelines

Results 1-25 (1066252)