MSBA-S - A pentacyclic sulfamate as a new option for radiotherapy of human breast cancer cells.

Many pentacyclic triterpenoids show anti-cancer and anti-inflammatory properties. Recently, we detected a pronounced cytotoxicity and radiosensitivity of two betulinyl sulfamates in human breast cancer cells. Besides betulinic acid scaffold (BSBA-S), we synthesized several new sulfamate-coupled scaffolds from oleanolic acid (OSBA-S), ursolic acid (USBA-S), platanic acid (PSBA-S) and maslinic acid (MSBA-S). Highest cytotoxicity was monitored in breast cancer cell lines after MSBA-S treatment showing in SRB assays IC50 values between 3.7 µM and 5.8 µM. Other sulfamate/triterpene conjugates, however, were less cytotoxic holding IC50 values between 6.6 µM and >50 µM, respectively. MSBA-S-treated breast cancer cells displayed significantly reduced clonogenic survival and an increased rate of apoptosis as compared to the other conjugates. In addition, MSBA-S in combination with irradiation resulted in effects on radiosensitivity in MDA-MB-231 cells (DMF10 = 1.14). In particular, ROS formation was strongly assessed in MSBA-S-treated breast cancer cells. Our findings suggest that the sulfamate derivative of maslinic acid MSBA-S might be a new option for the radiation therapy in breast cancer cells.

At3g53630 encodes a GUN1-interacting protein under norflurazon treatment.

Chloroplasts are semi-autonomous organelles, with more than 95% of their proteins encoded by the nuclear genome. The chloroplast-to-nucleus retrograde signals are critical for the nucleus to coordinate its gene expression for optimizing or repairing chloroplast functions in response to changing environments. In chloroplasts, the pentatricopeptide-repeat protein GENOMES UNCOUPLED 1 (GUN1) is a master switch that senses aberrant physiological states, such as the photooxidative stress induced by norflurazon (NF) treatment, and represses the expression of photosynthesis-associated nuclear genes (PhANGs). However, it is largely unknown how the retrograde signal is transmitted beyond GUN1. In this study, a protein GUN1-INTERACTING PROTEIN 1 (GIP1), encoded by At3g53630, was identified to interact with GUN1 by different approaches. We demonstrated that GIP1 has both cytosol and chloroplast localizations, and its abundance in chloroplasts is enhanced by NF treatment with the presence of GUN1. Our results suggest that GIP1 and GUN1 may function antagonistically in the retrograde signaling pathway.

Chemical synthesis, crystal structure, versatile evaluation of their biological activities and molecular simulations of novel pyrithiobac derivatives.

Since pyrithiobac (PTB) is a successful commercial herbicide with very low toxicity against mammals, it is worth exploring its derivatives for an extensive study. Herein, a total of 35 novel compounds were chemically synthesized and single crystal of 6-6 was obtained to confirm the molecular structure of this family of compounds. The novel PTB derivatives were fully evaluated against various biological platforms. From the bioassay results, the best AHAS inhibitor 6-22 displayed weaker herbicidal activity but stronger anti-Candida activity than PTB did. For plant pathogenic fungi, 6-26 showed excellent activity at 50 mg/L dosage. Preliminary insecticidal activity and antiviral activity were also observed for some title compounds. Strikingly, 6-5 exhibited a promising inhibitory activity against SARS-CoV Mpro with IC50 of 4.471 µM and a low cellular cytotoxicity against mammalian 293 T cells. Based on the results of molecular modeling, HOMO-1 was considered to be a factor that affects AHAS inhibition and a possible binding mode of 6-5 with SARS-CoV Mpro was predicted. This is the first time that PTB derivatives have been studied as biological agents other than herbicides. The present research hence has suggested that more attentions should be paid to compounds belonging to this family to develop novel agrochemicals or medicines.

In vivo and in vitro effects of the herbicide Roundup(®) on developmental stages of the trematode Echinostoma paraensei.

The exposure of wildlife and humans to toxic residues of Roundup(®) through agricultural practices or the food chain has been reported since the herbicide was found contaminating rivers. Glyphosate, N-(phosphonomethyl)glycine acid, is a nonselective post-emergent herbicide and is formulated as an isopropylamine salt with the surfactant taloamine polyethoxylate (POEA) representing the commercial formulation of Roundup(®). There is little knowledge about the effects of the herbicide on helminth parasites, particularly those whose life cycle is related to water bodies. Here we investigated the effects of the Roundup(®) on the food-borne trematode Echinostoma paraensei in experimental conditions using different developmental stages (eggs, miracidia, cercariae, metacercariae, newly excysted larvae (NEL), helminths at seven days and helminths at fourteen days). Three different herbicide concentrations were tested based on concentrations typically applied in the field: 225, 450 and 900 mg/L. Specimens were analyzed in vitro for hatching miracidia, mortality and excystment rate of metacercariae and in vivo for parasitic load and egg production. There was a significant difference in the hatching miracidia rate only for the newly embryonated eggs. The mortality of specimens and excystment rate of metacercariae were concentration-dependent. There was a significant difference in the miracidia mortality with respect to concentration until 56.3 mg/L. The same effect was observed for cercariae, and mortality was observed from 15 min onwards at concentrations of 225-900 mg/L. At low concentrations, mortality was detected after 30 min. The effects of the herbicide concentration on NEL and on helminths at seven and fourteen days showed a significant difference after 24 h. There was no significant difference in parasitic load and egg production after infection of rodents with exposed metacercariae. All developmental stages of the trematode E. paraensei were affected by Roundup(®) exposure under experimental conditions. These results suggest that dynamics of transmission of the trematode could be affected in the natural environments. The study also reinforces the usefulness of this trematode as a good model organism to test pesticides regarding human and environmental health.

Continuous, low-dose oral exposure to sodium chlorate reduces fecal generic Escherichia coli in sheep feces without inducing clinical chlorate toxicosis.

Our objectives were to determine an effective, yet safe, daily dose of sodium chlorate for reducing fecal shedding of generic Escherichia coli in mature ewes. In a completely randomized experimental design, 25 Targhee ewes (age ∼ 18 mo; BW = 62.5 ± 7.3 kg, mean ± SD) were assigned randomly to 1 of 5 sodium chlorate treatments, which were administered in the drinking water for 5 consecutive days. Treatments were control group (no sodium chlorate) and 4 targeted levels of daily sodium chlorate intake: 30, 60, 90, and 120 mg · kg(-1) BW · d(-1) for 5 d. Individual ewe ad libitum intake of water (with treatments) was measured daily, and BW was measured at the beginning of and 15 and 51 d after the 5-d treatment period. Serum chlorate, whole blood methemoglobin and packed-cell volume (PCV), and fecal generic E. coli and general Enterobacteriaceae coliforms were measured from corresponding samples collected at the end of the 5-d treatment period. Average daily intakes of sodium chlorate from drinking water treatments were 95%, 91%, 90%, and 83% of the target treatment intakes of 30, 60, 90, and 120 mg · kg(-1) BW · d(-1), respectively. Daily sodium chlorate intake remained constant for all treatment groups except for ewes offered 120 mg NaClO3 · kg(-1) BW · d(-1), which decreased (quadratic; P = 0.04) over the course of the 5-d treatment period. This decrease in sodium chlorate intake indicated that the 120-mg NaClO3 level may have induced either toxicity and/or an aversion to the drinking water treatment. Serum chlorate concentrations increased (quadratic; P < 0.001) with increasing sodium chlorate intake. At the end of the 5-d treatment period, mean (least squares ± SEM) serum chlorate concentrations for ewes offered 30, 60, 90, and 120 mg NaClO3 · kg(-1) BW · d(-1) were 15.6 ± 14.1, 32.8 ± 15.8, 52.9 ± 14.1, and 90.3 ± 14.1 µg/mL, respectively. Whole blood methemoglobin and PCV were similar (P = 0.31 to 0.81) among the control group and ewes offered sodium chlorate. Likewise, BW was not affected by sodium chlorate (P > 0.27). Ewes consuming approximately 55 mg NaClO3 · kg(-1) BW · d(-1) or more (i.e., ewes offered 60, 90, and 120 mg) had a >1.4 log unit reduction in fecal E. coli and Enterobacteriaceae coliforms compared with control ewes. We suggest that for a short-term, 5-d dosing strategy, 55 to 81 mg NaClO3 · kg(-1) BW · d(-1) is an effective, yet safe, daily oral dose range for mature ewes to achieve a 97% to 99% reduction in fecal shedding of generic E. coli.

Fluridone as a new anti-inflammatory drug.

Fluridone is a herbicide extensively utilized in agriculture for its documented safety in animals. Fluridone contains a 4(1H)-pyridone and a trifluoromethyl-benzene moiety, which are also present in molecules with analgesic and anti-inflammatory properties. The established absence of adverse effects of Fluridone on animals prompted us to investigate whether it could represent a new anti-inflammatory compound targeting human cells. In stimulated human monocytes, micromolar Fluridone inhibited cyclooxygenase-2 expression and the release of monocyte chemoattractant protein-1 and prostaglandin-E2, to a similar extent as Acetylsalicylic acid. Fluridone also inhibited the proliferation of aortic smooth muscle cells and reduced proliferation and cytokine release by human activated lymphocytes. The mechanism of Fluridone seems to rely on the dose-dependent inhibition of the nuclear translocation of nuclear factor-κB, a transcription factor playing a pivotal role in inflammation. Fluridone also inhibited the release from stimulated human monocytes of abscisic acid, a plant stress hormone recently discovered also in mammalian cells, where it stimulates pro-inflammatory responses. Interestingly, the mechanism of Fluridone's toxicity in plants relies on the inhibition of the enzyme phytoene desaturase, involved in the biosynthetic pathway of ß-carotene, the precursor of absciscic acid in plants. Finally, administration of Fluridone reduced peritoneal inflammation in Zymosan-treated mice. These results suggest that Fluridone could represent a new prototype of anti-inflammatory drug, also active on abscisic acid pro-inflammatory pathway.

Inhibition of 4-hydroxyphenylpyruvate dioxygenase by 2-[2-nitro-4-(trifluoromethyl)benzoyl]-1,3-cyclohexanedione.

Triketone herbicides are inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD), a key enzyme of the tyrosine transformation pathway, common for plants and animals. One of these herbicides, 2-[2-nitro-4-(trifluoromethyl)benzoyl]-1,3-cyclohexanedione (NTBC), is so selective and efficient that it can be applied as a medicine in a hereditary metabolic disease - tyrosinemia type I. In this paper the available information concerning the molecular mechanism of HPPD inhibition by NTBC, originating from experimental investigations as well as theoretical modeling, has been collected. It is supplemented by results of additional theoretical DFT and/or MP2 calculations of the energetic effects of individual elementary molecular transformations. All these data are discussed and a consistent picture of HPPD inhibition by NTBC is proposed.

Novel s-triazine-degrading bacteria isolated from agricultural soils of central Chile for herbicide bioremediation

s-Triazine-degrading bacterial strains were isolated from long-term simazine-treated agricultural soils of central Chile. The number of culturable heterotrophic bacteria of these agricultural soils (7 x 10(6) CFU/g of dry soil) was not affected by simazine application on field. The simazine-degrading bacterial strains P51, P52 and C53 were isolated by enrichment in minimal medium using simazine as the sole nitrogen source. Resting cells of strains P51 and P52 degraded >80 percent of simazine within 48 hrs, whereas strain C53 was able to remove >60 percent of the herbicide. The atzA and atzD genes of the s-triazine upper and lower catabolic pathways were detected in strains P51 and C53, while only atzD gene was observed in strain P52. To compare the bacterial 16S rRNA gene sequence structure, ARDRA were performed using the restriction enzymes Msp1 and Hha1. ARDRA indicated that strain P52 was a different ribotype than C53 and P51 strains. For further characterization the novel isolates were identified by 16S rRNA gene sequencing. Strains C53 and P51 belong to the genus Stenotrophomonas and the strain P52 belongs to the genus Arthrobacter . s -Triazine-degrading bacterial strains isolated from contaminated soils could be used as biocatalysts for bioremediation of these herbicides.

Actividades citotóxicas y antibacterianas de las raíces de Capparis zeylanica Linn / Antibacterial and Cytotoxic Activities of Capparis zeylanica Linn Roots

Se analizaron extractos crudos y un ácido graso, ácido octadec-7-en-5-ynoic (1), de la corteza de la raíz de Cappariszeylanica Linn. (familia de las Capparidaceae) para observar sus actividades antibacterianas frente a la bacteria Gram positiva y Gram negativa. Entre los extractos crudos, el extracto de cloroformo mostró una buena actividad frente a todos los organismos de prueba. El ácido graso (1) aislado del extracto de cloroformo mostró actividades antibacterianas frente a todos los organismos de prueba, a excepción de E. coli. Las actividades se compararon con un antibiótico estándar: la kanamicina. Las concentraciones inhibitorias mínimas (CIH) de 1, determinadas mediante la técnica de dilución en serie, fueron 64 mg/ml frente a Bacillus subtilis y Shigella dysenteriae. Las actividades citotóxicas del extracto crudo y del ácido graso (1) se observaron mediante el bioensayo de gambas en salmuera yel valor de LC50 del compuesto fue 6,27 mg/ml (AU)

Crude extracts and a fatty acid, octadec-7-en-5-ynoic acid (1), from the root bark of Capparis zeylanica Linn. (Fam. Capparidaceae) were screened for their antibacterial activities against Gram positive and Gram negative bacteria. Among the crude extracts, chloroform extract showed good activity against all test organisms. The fatty acid (1) isolated from chloroform extract exhibited antibacterial activities against test organisms except E. coli. The activities were compared to a standard antibiotic- kanamycin. The minimum inhibitory concentrations (MICs) of 1, determined byserial dilution technique, were found to be 64 mg/ml against Bacillus subtilis and Shigella dysenteriae. The cytotoxic activities of crude extract and fatty acid (1) were observed by brine shrimp biassay and LC50 value of the compound was found to be 6.27 mg/ml (AU)

Treatment of experimental chronic chagas disease with trifluralin.

We tested trifluralin against Trypanosoma cruzi in a model of chronic Chagas disease in mice. CF1 mice (n=148) were intraperitoneally infected with 10(5) trypomastigotes of T. cruzi, H510C8C3 clone. One hundred mice were partially treated with benznidazole. Mortality was 100% at day 41 in the control group (n=48). At day 90 of the chronic disease (74% survival) mice were divided into three groups and treated orally with trifluralin (50 mg/kg/day, n=26), benznidazole (50 mg/kg/day, n=25) and vehicle (peanut oil; control group, n=23) for 60 days. Electrocardiography (under pentobarbital anaesthesia, 30 mg/kg/dose), serologic immunofluorescence and microstrout were performed at the beginning and at the end of the treatment. Mice were sacrificed at day 10 after treatment; cardiac tissue was studied histopathologically and polymerase chain reaction (PCR) was performed. Spontaneous mortality was 30.43%, 3.85% and 4% in the control, trifluralin and benznidazole groups, respectively (significant survival, P=0.03). Microstrouts were negative in all three groups. Negative immunofluorescence titers were 0%, 16% (P=0.05) and 29% (P<0.02) in the control, trifluralin and benznidazole groups, respectively. The prevailing electrocardiographic disorder was prolongation of the PR interval in the control group, which was not significantly altered in trifluralin- and benznidazole-treated mice, suggesting that trifluralin and benznidazole improve or even stop the damage caused by the disease on the conduction system. Trifluralin- and benznidazole-treated animals showed similar histologic patterns of myocarditis. PCR results were negative for benznidazole and trifluralin (100% and 70.8%, respectively). These results show the therapeutic potential of trifluralin in the treatment of chronic Chagas disease.

Lack of modifying effects of atrazine and/or tamoxifen on thyroid carcinogenesis in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine (DHPN).

The modifying effects of atrazine, and/or tamoxifen, on thyroid carcinogenesis were investigated in a rat two-stage carcinogenesis model following N-bis(2-hydroxypropyl)nitrosamine (DHPN) initiation. Five-week-old male F344 rats were given a single subcutaneous injection of DHPN (2800 mg/kg, body weight) or vehicle alone. Starting 1 week later, the animals were fed a diet supplemented with 0, 5, 50 or 500 ppm of atrazine, 500 ppm atrazine plus 5 ppm tamoxifen, or 5 ppm tamoxifen in the DHPN-treated groups, and 0 or 500 ppm of atrazine in the DHPN-untreated groups for 24 weeks. At autopsy major organs, including the thyroid, pituitary, liver, kidney, testis, epididymis, and brain, were collected and histopathologically examined. Body weights were significantly (P<0.05) decreased by the high doses of atrazine or tamoxifen, the effect being enhanced in combination. Relative thyroid weights were significantly increased (P<0.05) only in the tamoxifen-treated group and pituitary weights were elevated with 500 ppm atrazine plus tamoxifen (P<0.05). Relative liver weights were increased by the high dose of atrazine. However, the atrazine and/or tamoxifen treatments did not induce significant histopathological changes in the major organs, including the thyroid, nor cause significant changes in serum TSH levels. These results suggest that neither atrazine nor tamoxifen may promote thyroid carcinogenesis, alone as well as in combination.

Genetically modified plants: the stakes.

Generically modified plants (GMP) are massively used on the American continent in Australia and in China, since they represent an unquestionable potential for progress. New attributes are therefore devoted to the human and animal diet, to the facilitating of culture management, to the reducing of the chemical fertilizer and pesticide usage, and to the conquest of new cultural spaces. Considering itself to be flawed by a too hasty plunge into the market, concomitant with sagging evaluations of other innovations, Europe is confronted by a strong societal debate which blocks GMP cultures and orientates the research towards an evaluation of the environmental and public health risks and an evaluation of their economical and sociological impacts. The authors encourage this societal debate in order to arbitrate the presence of transgenes in conventional productions and products, to define the accepted rules of responsibility, to decide what is not acceptable, and to involve the more upstream actors and operators of the innovation process, all that keeping in mind the agronomical, ecological and economical repercussions of their decisions.

Results of dental amalgam removal and mercury detoxification using DMPS and neural therapy.

Sixty consecutive patients who had undergone replacement of dental amalgam fillings and a protocol of nutritional support and heavy metal detoxification using dimercapto-propanyl-sulfate and neural therapy were surveyed. A questionnaire was mailed to the patients and 42 responded, resulting in a response rate of 70%. The reasons for undergoing treatment were many, ranging from a patient's desire to avoid potential health problems in the future to treatment of serious current disease. Although medical diagnoses were made when possible before treatment, this survey studied only the patients' estimations of their most distressing symptoms and their evaluations of response to treatment. The most common complaints were problems with memory and/or concentration; muscle and/or joint pain; anxiety and insomnia; stomach, bowel, and bladder complaints; depression; food or chemical sensitivities; numbness or tingling; and eye symptoms, in descending order of frequency. The most distressing symptoms were headache and backache, fatigue, and memory and concentration problems. Headache and backache responded best to treatment, but all symptoms showed considerable improvement on average. Of the respondents, 78% reported that they were either satisfied or very satisfied with the results of treatment, and 9.5% reported that they were disappointed.

From toxicological problem to therapeutic use: the discovery of the mode of action of 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC), its toxicology and development as a drug.

NTBC is a triketone with herbicidal activity that has been shown to have a novel mode of action by inhibiting the enzyme 4-hydroxyphenylpyruvate dioxygenase in plants. Early studies on the toxicity of this compound found that rats treated with NTBC developed corneal lesions. Investigations aimed at understanding the mechanistic basis for the ocular toxicity discovered that the rats developed tyrosinaemia and excreted large amounts of 4-hydroxyphenylpyruvate and 4-hydroxyphenyllactate, owing to inhibition of the hepatic enzyme 4-hydroxyphenylpyruvate dioxygenase. The corneal lesions resemble those seen when rats are fed a diet supplemented with tyrosine, leading us to conclude that the ocular toxicity seen with NTBC is a consequence of a marked and sustained tyrosinaemia. Studies in collaboration with Professor Sven Lindstedt showed that NTBC was a potent inhibitor of purified human liver 4-hydroxyphenylpyruvate dioxygenase. This interaction lead to the concept of using NTBC to treat patients with tyrosinaemia type 1, to block or reduce the formation of toxic metabolites such as succinylacetoacetate in the liver. Zeneca Agrochemicals and Zeneca Pharmaceuticals made NTBC available for clinical use and, with the approval of the Swedish Medical Products Agency, a seriously ill child with an acute form of tyrosinaemia type 1 was successfully treated in February 1991. Subsequently, other children with this inborn error of metabolism in Sweden and other countries have been treated with NTBC. The drug is now available to those in need via Swedish Orphan AB.

Pitiriasis rubra pilaris: estudio clínico en relación a nueve casos / Pityriasis rubra pilaris: clinical study about 9 cases

La Pitiriasis Rubra Pilares (PRP) es una dermatosis de etiología desconocida, caracterizada por pápulas foliculares, queratodermia palmoplantar y rash cefálico. Afecta por igual a ambos sexos, y su incidencia máxima es en la primera y quinta década de la vida. Existen clasificaciones que tienen en cuenta las características clínicas, edad y pronóstico, que las subdividen en cinco tipos bien definidos (Griffiths). De este estudio se presentan nueve casos de Pitiriasis Rubra Pilaris, con sus caracteres clínicos, evolución y terapéutica

[Effect of the herbicide Herbazin-50 (simazine) on the wound process in animals]. / Vliianie na kherbitsida kherbazin-50 (simazin) vurkhu raneviia protses pri zhivotnite.

Herbazin 50 was used as an experimental model to record species differences in the process of wound healing in horses, cattle, and sheep. It was established that the local and oral application of this herbicide inhibited wound healing, and this effect was more strongly manifested in the phase of hydratation. There were clearly expressed species-associated variations: in horses the elimination of the irritant was achieved through a severe inflammation response of a purulent character, while in cattle the rapid response of the connective tissue was leading, with concurrent premature maturation. Changes set in under the effect of the herbicide, consisting in the alkalinization of the wound exudate, which led to changes in the wound microflora.

[Effect of herbazin 50 on the course of suppurative surgical infection in sheep]. / Vliianie na kherbazin 50 vurkhu protichaneto na gnoina khirurgicheska infektsiia pri ovtsete.

Twelve sheep, divided into two groups of 6 animals each, were used. The first (test) group was offered herbazin -50 with the feed in the course of 90 days after which the animals were infected via the joints with Corynebacterium pyogenes. The second (control) group was also infected with the same pathogen in the same way. During the time the preparation was given and 30 days post infection the animals were kept under observation, following up their clinical, condition, and the occasional morphological and biochemical changes taking place in the blood and the immunobiologic responsiveness. It was found that sheep treated with herbazin -50 with a following infection with Corynebacterium pyogenes raised their blood levels of sugar, total protein, potassium, sodium, magnesium, SGOT, SGPT, and manifested an increased ESR, and lower calcium, inorganic phosphorus, carotene, vitamin A, and cholesterine serum level. It was also established that surgical infections brought about through such introduction of C. pyogenes developed much more rapidly and ran a much more severe course in sheep after the preliminary treatment with herbazin -50. It is believed that they emerged after suppressing the immunologic responsiveness with the use of the preparation.