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1.
World J Microbiol Biotechnol ; 36(10): 152, 2020 Sep 14.
Article in English | MEDLINE | ID: mdl-32924087

ABSTRACT

The dynamics of volatilomes emitted during the interaction between plant-growth-promoting bacteria (PGPB) and the phytopathogen Fusarium solani were evaluated for 5 days. The first screening was done to evaluate the antagonist activity of volatile compounds emitted by PGPB against F. solani. Volatilomes from 11 PGPB were determined individually and together with F. solani by using solid-phase microextraction coupled to gas-chromatography-mass spectrometry. Isolates of PGPB belonged to the Bacillus genus and inhibited from 18 to 24% the fungal mycelium growth. The isolates also induced morphological alterations of fungal hyphae, like small globular vesicles and the formation of chlamydospores, suggesting a stress mechanism response by the fungus. Volatilome profile showed 49 different compounds that appeared in the bacterial-fungal interaction, such as ketones, sesquiterpenes, monoterpenoids, alkanes, alkenes, carboxylic acids, and fatty acids. Some ketones and alcohols were detected in high abundance only in the interaction PGPB-fungus at 3 and 5 days. Bacillus circulans A19, Bacillus amyloliquefaciens A21, and Bacillus wiedmannii S18 shared a group of emitted alcohols and ketones when they were exposed to F. solani. F. solani produced its own volatilome profile, with the presence of sesquiterpenes, such as α-cubebene and caryophyllene, which increased significantly in co-incubation with the tested bacteria, suggesting chemical communication between them.


Subject(s)
Antifungal Agents/pharmacology , Bacteria/metabolism , Bacterial Physiological Phenomena , Fusarium/drug effects , Microbial Interactions/physiology , Plant Development/physiology , Volatile Organic Compounds/pharmacology , Alkanes/pharmacology , Alkenes/pharmacology , Antifungal Agents/chemistry , Bacillus , Bacillus amyloliquefaciens , Bacteria/drug effects , Carboxylic Acids/pharmacology , Fatty Acids/pharmacology , Fusarium/growth & development , Fusarium/pathogenicity , Ketones/pharmacology , Microbial Interactions/drug effects , Monoterpenes/pharmacology , Mycelium/growth & development , Plant Diseases/microbiology , Sesquiterpenes/pharmacology , Soil Microbiology , Volatile Organic Compounds/chemistry
2.
3 Biotech ; 10(7): 292, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32551213

ABSTRACT

The aims of this work were to screen isolated bacteria with a dual capacity: to inhibit Fusarium solani and to promote plant growth. Also, volatile compounds that would be responsible for that effect were identified. Seventy bacterial strains from the air, agricultural soils, hydrocarbons-contaminated soils, and extremophile soils were tested. The former were identified by Matrix-Assisted Laser Desorption/Ionization-time of flight mass spectrometry and 16S rDNA sequencing. The plant growth-promoting bacteria (PGPB) and their capability for phosphate solubilization, siderophores production, and indole production were determined. Twenty isolates from Bacillus and Pseudomonas genera inhibited the mycelial growth up to 40% in direct assays. Eleven isolates significantly inhibited mycelial growth in 18-24% via volatile emissions. Volatile compounds related to antifungal activity or stress response include ketones, sesquiterpenes, monoterpenoids, alkanes, and fatty acids. Our results support the potential of these PGPB to act as biocontrol agents against fungal pathogens via volatile emissions.

3.
Ann Oncol ; 31(8): 1001-1010, 2020 08.
Article in English | MEDLINE | ID: mdl-32416251

ABSTRACT

BACKGROUND: Alpelisib (α-selective phosphatidylinositol 3-kinase inhibitor) plus fulvestrant is approved in multiple countries for men and postmenopausal women with PIK3CA-mutated, hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer following progression on or after endocrine therapy. A detailed understanding of alpelisib's safety profile should inform adverse event (AE) management and enhance patient care. PATIENTS AND METHODS: AEs in the phase III SOLAR-1 trial were assessed in patients with and without PIK3CA mutations. The impact of protocol-specified AE-management recommendations was evaluated, including an amendment to optimize hyperglycemia and rash management. RESULTS: Patients were randomly assigned to receive fulvestrant plus alpelisib (n = 284) or placebo (n = 287). The most common grade 3/4 AEs with alpelisib were hyperglycemia (grade 3, 32.7%; grade 4, 3.9%), rash (grade 3, 9.9%), and diarrhea (grade 3, 6.7%). Median time to onset of grade ≥3 toxicity was 15 days (hyperglycemia, based on fasting plasma glucose), 13 days (rash), and 139 days (diarrhea). Metformin alone or in combination with other antidiabetic agents was used by most patients (87.1%) with hyperglycemia. Preventive anti-rash medication resulted in lower incidence (any grade, 26.7% versus 64.1%) and severity of rash (grade 3, 11.6% versus 22.7%) versus no preventative medication. Discontinuations due to grade ≥3 AEs were lower following more-detailed AE management guidelines (7.9% versus 18.1% previously). Patients with PIK3CA mutations had a median alpelisib dose intensity of 248 mg/day. Median progression-free survival with alpelisib was 12.5 and 9.6 months for alpelisib dose intensities of ≥248 mg/day and <248 mg/day, respectively, compared with 5.8 months with placebo. CONCLUSIONS: Hyperglycemia and rash occurred early during alpelisib treatment, while diarrhea occurred at a later time point. Early identification, prevention, and intervention, including concomitant medications and alpelisib dose modifications, resulted in less severe toxicities. Reductions in treatment discontinuations and improved progression-free survival at higher alpelisib dose intensities support the need for optimal AE management. CLINICALTRIALS. GOV ID: NCT02437318.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Breast Neoplasms , Phosphatidylinositol 3-Kinases , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/drug therapy , Female , Fulvestrant , Humans , Male , Receptor, ErbB-2 , Receptors, Estrogen , Thiazoles
4.
Proc Biol Sci ; 270(1512): 249-57, 2003 Feb 07.
Article in English | MEDLINE | ID: mdl-12614573

ABSTRACT

For the Makiritare (Ye'Kuana) native people of the Alto Orinoco (Venezuela), earthworms (Anellida: Glossoscolecidae) are an important component of the diet. Two species in particular are widely consumed: 'kuru' (Andiorrhinus kuru n. sp.) and 'motto' (Andiorrhinus motto). We analysed eviscerated kuru body proper, and whole and smoked preparations of motto for their content of protein and amino acids, fatty acids and 20 minerals and trace elements. The samples contained large amounts of protein (64.5-72.9% of dry weight), essential amino acids, calcium and iron together with notable quantities of other important elements, indicating that these earthworms contain potentially useful quantities of many nutrients that are critical to the health of the humans who consume them.


Subject(s)
Indians, South American , Nutritive Value , Oligochaeta , Amino Acids , Animals , Fatty Acids/analysis , Humans , Lipids/analysis , Trace Elements/analysis , Venezuela
5.
Proc Biol Sci ; 267(1459): 2247-52, 2000 Nov 22.
Article in English | MEDLINE | ID: mdl-11413639

ABSTRACT

At least 32 Amerindian groups in the Amazon basin use terrestrial invertebrates as food. Leaf- and litter-consuming invertebrates provide the more important, underestimated food sources for many Amerindian groups. Further, litter-consuming earthworms are also an important food resource for the Ye'Kuana (also known as Makiritare) in the Alto Orinoco (Amazonas, Venezuela). By selecting these small invertebrates the Amerindians are choosing their animal food from those food webs in the rainforest which have the highest energy flow and which constitute the greatest renewable stock of readily available nutrients. Here we show that the consumption of leaf- and litter-feeding invertebrates as a means of recovering protein, fat and vitamins by the forest-living peoples offers a new perspective for the development of sustainable animal food production within the paradigm of biodiversity maintenance.


Subject(s)
Dietary Proteins , Food Chain , Indians, South American , Animals , Ants , Humans , Insecta , Invertebrates , Isoptera , Oligochaeta , Plant Leaves , Venezuela
6.
Acta Cient Venez ; 49(3): 201-3, 1998.
Article in English | MEDLINE | ID: mdl-10030046

ABSTRACT

Cosmopolites sordidus is an important pest on banana plantations worldwide. The chemistry of the aggregation pheromone of this insect has been recently resolved and here we present the first evidence from field trails that sordidin, a compound from the male released aggregation pheromone, attracts significant number of weevils only if host plant odors are also present. Sordidin attracts few insects when it is presented without the host plant tissue. However, the attractiveness of host plant tissue increases more than tenfold when it is presented simultaneously with sordidin in field traps. We confirm experimentally that sordidin may be used as part of a system for mass trapping and monitoring this insect.


Subject(s)
Bridged Bicyclo Compounds/pharmacology , Coleoptera/drug effects , Pheromones , Zingiberales/parasitology , Animals , Drug Synergism
7.
Mutat Res ; 375(2): 167-81, 1997 Apr 29.
Article in English | MEDLINE | ID: mdl-9202727

ABSTRACT

The exposure of food to ionizing radiation is being progressively used in many countries to inactivate food pathogens, to eradicate pests, and to extend shelf-life, thereby contributing to a safer and more plentiful food supply. To ensure free consumer choice, irradiated food will be labelled as such, and to enforce labelling, analytical methods to detect the irradiation treatment in the food product itself are desirable. In particular, there is a need for simple and rapid screening methods for the control of irradiated food. The DNA comet assay offers great potential as a rapid tool to detect whether a wide variety of foodstuffs have been radiation processed. In order to simplify the test, the agarose single-layer set-up has been chosen, using a neutral protocol. Interlaboratory blind trials have been successfully carried out with a number of food products, both of animal and plant origin. This paper presents an overview of the hitherto obtained results and in addition the results of an intercomparison test with seeds, dried fruits and spices are described. In this intercomparison, an identification rate of 95% was achieved. Thus, using this novel technique, an effective screening of radiation-induced DNA fragmentation is obtained. Since other food treatments also may cause DNA fragmentation, samples with fragmented DNA suspected to have been irradiated should be analyzed by other validated methods for irradiated food, if such treatments which damage DNA cannot be excluded.


Subject(s)
DNA Damage , Food Irradiation , Mutagenicity Tests/methods , Animals , Bone Marrow/chemistry , Chickens , DNA Mutational Analysis/methods , Electrophoresis, Agar Gel/methods , Methods , Seeds , Swine , Trout
8.
Rev Med Chil ; 124(6): 681-7, 1996 Jun.
Article in Spanish | MEDLINE | ID: mdl-9041724

ABSTRACT

BACKGROUND: Colorectal carcinoma is the fifth cause of cancer deaths among women and the sixth among men. AIM: To retrospectively analyze the distribution by sex, age, localization and the pathologic features of resected large bowel adenocarcinomas at a surgical service. MATERIALS AND METHODS: All biopsy reports of resected large bowel carcinomas between 1959 and 1995 were analyzed. Twenty six reports were discarded. Available histological slides were re-examined. RESULTS: Twenty five cases (2.5%) had two synchronous tumors and 14 subjects (1.4%) had two different resections due to cancer (metachronic tumors). Sixty percent of tumors were located in the rectum and sigmoid, 74% were well differentiated, 17% poorly differentiated. Mucinous and signet ring cell variants were found in younger subjects and in 5.1% and 2.3% of all patients respectively. Eighty four percent of tumors were beyond the muscularis at the moment of resection and 38% had lymph node metastasis. Comparing the 1959-1979 with the 1980-1995 period, the mean age of patients increased from 60 to 65 years old and rectal cancer frequency decreased from 37.8 to 25.4%. CONCLUSIONS: Colorectal carcinoma is still diagnosed at an advanced stages and the changes of the natural history of the disease observed in the two analyzed periods are similar to those reported in USA and Colombia.


Subject(s)
Adenocarcinoma/pathology , Intestinal Neoplasms/pathology , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Neoplasm Invasiveness , Retrospective Studies , Sex Distribution
9.
J Chem Ecol ; 19(8): 1703-20, 1993 Aug.
Article in English | MEDLINE | ID: mdl-24249235

ABSTRACT

Attraction to host plants by adultRhynchophorus palmarum (L.) palm weevils was studied in the field and in the laboratory. Chemical analysis revealed the presence of ethanol and ethyl-acetate in stems of coco palms and in pineapple fruits and of pentane, hexanal, and isopentanol in coco stems. In the olfactometer, the first two compounds and isoamyl-acetate were attractive to the insects and the last three compounds, although not attractive by themselves, increased attractiveness when mixed with the first two compounds. Mixtures of these compounds, in proportions similar to the one occurring in attractive plant tissue, were as attractive as natural coconut tissue. In the field, the chemical compounds, either presented alone or as a mixture, did not attract the weevil. Males produce an aggregation pheromone when smelling ethyl-acetate. Rhynchophorol, 2(E)-6-methyl-2-hepten-4-ol, the known active component of the aggregation pheromone, attracts weevils in the olfactometer and in the field only if plant tissue, ethyl-acetate, or the above-mentioned odor mix are present. We propose that a complex mix of ethanol, ethyl-acetate, pentane, hexanal, isolamyl-acetate, and/or isopentanol serve as a short-range orientation cue to fresh wounds on the plant and that additional host odors, attracting weevils from a distance, have still to be discovered. Rhynchophorol can be considered to be a Synergist, having an anemotactic action at a distance. We recommend the use of retention traps baited with rhynchophorol, ethyl-acetate, and sugar cane as an alternative control method for the pest.

10.
J Chem Ecol ; 18(6): 841-6, 1992 Jun.
Article in English | MEDLINE | ID: mdl-24254087

ABSTRACT

DIMBOA glucoside (2-O-/gb-D-glucopyranosyl-4-hydroxy-7-meth-oxy-1,4-benzoxazin-3-one), the main hydroxamic acid (Hx) in intact wheat plants, was detected in the honey dew ofRhopalosiphum padi feeding on seedlings of six wheat cultivars that differed in their concentration of Hx, suggesting that the chemical circulates in the phloem. Neither the aglucone (DIMBOA) nor its main breakdown product were found in any of the honeydew samples. Honey dew production by aphids caged on seedlings of the wheat cultivars and DIMBOA glucoside concentrations in the honeydew followed biphasic curves when plotted against Hx concentration, suggesting passive ingestion of the chemical from the phloem at low Hx concentrations and limited ingestion due to feeding deterrency by Hx in mesophyll cells at high Hx concentrations. The presence of plant toxins such as Hx glucosides in the phloem sap, the main ingesta of aphids, and in the mesophyll cells, has major implications for plant defense, through a feeding deterrent effect during stylet penetration, and deterrency (antixenosis) along with antibiosis during feeding.

11.
Radiat Res ; 95(2): 317-26, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6611851

ABSTRACT

The induction and repair of DNA damage in single endothelial cells of rat cerebral cortex capillaries were studied in vivo and in vitro. Capillaries from the cerebral cortex were prepared in suspension, embedded in agarose on microscope slides, and treated with alkaline solution (unwinding of DNA). After neutralization the slides were stained with the fluorescent dye acridine orange and endothelial cell nuclei were evaluated in a microscope photometer. The intensity of the red fluorescence (from single-stranded DNA) divided by the green fluorescence (from double-stranded DNA) was used as a measured of DNA strand breaks. The results showed that most DNA strand breaks were repaired within 30 min postirradiation. A linear dose-effect relationship was found up to 18 Gy. Similar results were obtained from in vitro and in vivo experiments. Cysteamine administered 20 min before irradiation in vivo gave a protective effect on the cells studied. An EMF of 1.3 was determined.


Subject(s)
Cerebral Cortex/radiation effects , Cysteamine/pharmacology , DNA Repair/drug effects , DNA/radiation effects , Radiation-Protective Agents/pharmacology , Animals , Cobalt Radioisotopes , Dose-Response Relationship, Radiation , Female , Gamma Rays , Rats , Rats, Inbred Strains , Time Factors
12.
Article in English | MEDLINE | ID: mdl-6603433

ABSTRACT

DNA strand breaks and cell pycnosis induced by 60Co gamma radiation were studied in the developing rat cerebellum. Rats 2, 5 or 12 days old were irradiated and the repair of DNA strand breaks was studied at various intervals up to seven hours. DNA strand breaks were repaired in 30 min and post-repair DNA degradation was observed about 90 min after irradiation in 12 day old rats and some time later in the younger ones. The pycnotic activity in the external granular layer of the cerebellar cortex seen in histological preparations developed in a similar way, the older rats showing earlier signs of cell pycnosis and a faster degradation of DNA. A correspondence was found between DNA degradation and cell pycnosis.


Subject(s)
Cerebellar Cortex/growth & development , DNA/radiation effects , Animals , Cerebellar Cortex/cytology , Cerebellar Cortex/radiation effects , Cobalt Radioisotopes , DNA Repair , Female , Gamma Rays , Male , Rats , Rats, Inbred Strains , Time Factors
13.
Acta Radiol Oncol ; 22(2): 163-6, 1983.
Article in English | MEDLINE | ID: mdl-6310971

ABSTRACT

Radiation induced cell pyknosis was analysed in the cerebellar cortex of developing rats. Rats of 1, 5 or 10 days of age were irradiated with 60Co and pyknotic cells were evaluated with respect to time after irradiation with 0.1 Gy and with respect to dose in the range 0.05 to 1.0 Gy. In all ages pyknotic cells began to appear about 2 hours after irradiation, a maximum was reached at about 8 hours. With a dose of 0.1 Gy, control values were obtained after 24 hours. The effects varied linearly with dose up to 1 Gy and no threshold seemed to exist at low doses.


Subject(s)
Cerebellum/radiation effects , Animals , Cerebellum/cytology , Cerebellum/growth & development , Cobalt Radioisotopes , Dose-Response Relationship, Radiation , Female , Gamma Rays , Male , Rats , Rats, Inbred Strains , Time Factors
14.
Acta Radiol Oncol ; 22(3): 233-9, 1983.
Article in English | MEDLINE | ID: mdl-6312763

ABSTRACT

Rats of one or ten days of age were irradiated with low doses of gamma radiation, and synthesis of DNA was examined by the incorporation of 3H-thymidine in the cerebellum and the rest of the brain in vivo. DNA synthesis was depressed in both parts of the brain but the effects were larger in cerebellum. A minimum was found about 10 hours after irradiation in the older rats and later (18 h) in the younger ones. The dose response, in 10-day-old rats, was biphasic and showed that cerebellum was more affected. Autoradiographs showed that fewer cells entered the cycle and those synthesizing showed a depressed rate of synthesis. These findings are discussed in relation to induction of cell death.


Subject(s)
Brain/radiation effects , Cobalt Radioisotopes/adverse effects , DNA/radiation effects , Age Factors , Animals , Brain/metabolism , Cerebellum/metabolism , Cerebellum/radiation effects , DNA/biosynthesis , Dose-Response Relationship, Radiation , Female , Male , Rats , Rats, Inbred Strains , Time Factors
15.
Growth ; 46(4): 355-66, 1982.
Article in English | MEDLINE | ID: mdl-6187631

ABSTRACT

Newborn rats were irradiated with 60Co gamma rays. Doses of 0, 0.8 or 1.6 Gy were given to the whole body. The body and brain weights, DNA and RNA contents of the brain and 3H-thymidine or H-uridine incorporated by the brain were measured at 5, 10, or 15 days after birth. A dose of 1.6 Gy produced alterations in the brain weight and the DNA and RNA contents of the brain while no clear effects could be detected after 0.8 Gy.


Subject(s)
Brain/radiation effects , DNA/biosynthesis , RNA/biosynthesis , Rats/growth & development , Animals , Body Weight/radiation effects , Brain/anatomy & histology , Brain/growth & development , Brain/metabolism , Female , Gamma Rays , Male , Organ Size/radiation effects , Rats, Inbred Strains , Thymidine/metabolism , Tritium , Uridine/metabolism
16.
Article in English | MEDLINE | ID: mdl-315382

ABSTRACT

Rats, 5, 10 or 25 days old, were 60 Co gamma irradiated. The induction of DNA strand breaks was studied after killing the rats within 1 min after irradiation, and the repair of the induced breaks after various intervals up to 180 min. Cell suspensions were prepared from the brain and samples were transferred into alkaline solutions. The fraction of DNA remaining double-stranded after 30 min alkali treatment was estimated after separation of single- and double-stranded DNA on hydroxylapatite. The amount of DNA strand breaks induced per Gray (1--8 Gray) was found to be in accordance with earlier in vivo studies of the mouse small intestine and mouse spleen. The DNA strand breaks in the rat brain induced by 4 Gray 60Co gamma irradiation were repaired 30 min after irradiation in all age groups studied.


Subject(s)
Brain/radiation effects , DNA Repair , DNA/radiation effects , Animals , Animals, Newborn , Brain/pathology , Cell Survival/radiation effects , Cells, Cultured , Cobalt Radioisotopes , Gamma Rays , Rats
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