RESUMEN

L-histidinium hydrogen oxalate (L-HisH)(HC2O4) crystal is formed from amino acid. L-histidine with oxalic acid whose vibrational high pressures behavior have not yet been investigated in the literature. Here we synthesized (L-HisH)(HC2O4) crystal by slow solvent evaporation method in a 1:1 ratio of L-histidine and oxalic acid. In addition, a vibrational study of (L-HisH)(HC2O4) crystal as a function of pressure was performed via Raman spectroscopy in the pressure range of 0.0-7.3 GPa. From analysis of the behavior of the bands within 1.5-2.8 GPa, characterized by the disappearance of lattice modes, the occurrence of a conformational phase transition was noted. A second phase transition, now from structural type, close to 5.1 GPa was observed due to the incidence of considerable changes in lattice and internal modes, mainly in vibrational modes related to imidazole ring motions.

RESUMEN

Aiming of self-sustainable production, the search for biodegradable and biocompatible materials has brought with it the need to know the physicochemical and dielectric characteristics of polysaccharide-based composite structures, which can be used as important and promising raw materials for biotechnology and electronic industries. Galactomannans are polysaccharides, extracted from seeds and microbiological sources, consisting of mannose and galactose. In this context, this work aimed to extract, purify and characterize by XRD, FTIR and impedance spectroscopy galactomannan obtained from seeds of Adenanthera pavonina L. The purification process was made with ethyl alcohol at concentrations of 70, 80 and 90 %. Polymeric films were prepared by solvent slow evaporation at low temperatures. XRD measurements revealed that Galactomannan from Adenanthera pavonina L., after purification, has a semi-crystalline structure due to the identification of two peaks the first between 5.849° and 6.118° and the second between 20.011° and 20.247°. FTIR spectra showed the functional groups associated with monosaccharides of the galactomannan from Adenanthera pavonina L. seeds, as well as the typical polysaccharide bands and peaks, confirmed by literature data. The impedance results give an increment on the state-of-the-art of this biomaterial by showing the existence of dielectric relaxations, independent of the degree of purification, using the dielectric modulus formalism. The permittivity analysis reveals the presence of water in the structure of the film, whose dipoles contribute to the relatively high value of the dielectric constant. From the results obtained, it can be concluded that purified galactomannan has the potential for possible applications in the electronics industry as a green and eco-friendly dielectric material.

Asunto(s)

Fabaceae , Mananos , Mananos/análisis , Mananos/química , Fabaceae/química , Polisacáridos/química , Galactosa , Semillas/química , Materiales Biocompatibles

RESUMEN

The association between exposure to air pollutants and respiratory diseases is well known. This study aimed to identify the association between this exposure and hospitalizations for COVID-19 in São José dos Campos, SP, a medium-sized city, between April 2020 and April 2021. Hospitalization data, concerning code B34.2, was supplied by DATASUS, and data concerning pollutants and climate variables were supplied by CETESB. Cases were quantified by sex, age, length of hospital stay in days, and type of discharge, whether hospital discharge or death. The negative binomial regression model was chosen. Estimates were produced for the relative risk (RR) of significant exposure to pollutants (P≤0.05) with a 10 µg/m3 increase of pollutant, as well as for excess hospitalizations. There were 1873 hospitalizations, with a daily average of 4.7 (±3.8), ranging from zero to 21: 716 deaths (38.2%) were recorded, 1065 admissions were men, and women were less susceptible (OR=0.82). The average age of women was higher than that of men; in cases of death, men were older than women; discharged patients were younger. All the above variables were significant. The risk of ozone exposure was higher and more significant in Lag 2, and the risk of nitrogen dioxide exposure was high in Lag 3, which was the period of the highest increase in hospitalizations, at 11.3%. The findings of this study, the first conducted in Brazil, corroborate the results of studies conducted in other centers.

Asunto(s)

Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Masculino , Humanos , Femenino , Brasil/epidemiología , Contaminación del Aire/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Hospitalización , Material Particulado

RESUMEN

Constitutional genomic imbalances are known to cause malformations, disabilities, neurodevelopmental delay, and dysmorphia and can lead to dysfunctions in the cell cycle. In extremely rare genetic conditions such as small supernumerary marker chromosomes (sSMC), it is important to understand the cellular consequences of this extra marker, as well the factors that contribute to their maintenance or elimination through successive cell cycles and phenotypic impact. The study of chromosomal mosaicism provides a natural model to characterize the effect of aneuploidy on genome stability and compare cells with the same genetic background and environment exposure, but differing in the presence of sSMC. Here, we report the functional characterization of different cell lines from two familial patients with mosaic sSMC derived from chromosome 12. We performed studies of proliferation dynamics, stability, and variability of these cells using fluorescent in situ hybridization (FISH), sister chromatid exchanges (SCE), and conventional staining. We also quantified the telomere-related genomic instability of sSMC cells using 3D telomeric profile analysis by quantitative-FISH. sSMC cells exhibited differences in the cell cycle dynamics compared to normal cells. First, the sSMC cells exhibited lower proliferation index and higher frequency of SCE than normal cells, associated with a higher level of chromosomal instability. Second, sSMC cells exhibited more telomeric-related genomic instability. Lastly, the differences of sSMC cells distribution among tissues could explain different phenotypic repercussions observed in patients. These results will help in our understanding of the sSMC stability, maintenance during cell cycle, and the cell cycle variables involved in the different phenotypic manifestations.

Asunto(s)

Cromosomas Humanos Par 12 , Mosaicismo , Padre , Marcadores Genéticos/genética , Inestabilidad Genómica/genética , Humanos , Hibridación Fluorescente in Situ , Masculino , Núcleo Familiar

RESUMEN

Raman spectroscopy and synchrotron radiation X-ray diffraction have been used to study the effect of pressure on 2-(-α-methylbenzylamino)-5-dinitropyridine (MBANP). Several changes are observed with increasing pressure in the Raman spectra of this system, such as splitting of various bands and disappearance of bands. Discontinuous shifts in wavenumber vs pressure plot indicate that a conformational phase transition takes place around 0.5 GPa. The behavior of the Raman spectra indicates that MBANP molecules present conformational phase transition at high-pressure. X-ray diffraction, performed with synchrotron radiation, confirms the conformational changes observed by Raman experiments around 0.5 GPa. The pressure provokes a rotational movement of the benzene ring which can be associated with the conformational phase transition.

Asunto(s)

Espectrometría Raman , Sincrotrones , Conformación Molecular , Transición de Fase , Espectrometría Raman/métodos , Difracción de Rayos X

RESUMEN

Tris(glycinato)chromium(III) monohydrate [Cr(C2H4NO2)3·H2O] crystals were grown through the slow solvent evaporation method. The crystals were studied by Fourier transform infrared (FTIR) and Raman spectroscopy at room temperature. The assignments of vibration modes were performed using the Density Functional Theory (DFT). Thermal analyses (TGA, DTA, and DSC), X-ray diffraction (XRD), and Raman were used to study the phase changes on the crystals under high- and low-temperature conditions. Temperature-dependent XRPD measurements were carried out in the interval of 473-12 K. Several changes were observed in the patterns, like the appearance of new peaks and the disappearance of peaks occurring within 373-393 K due to water loss. In addition, the Raman measurements were performed in the 423-10 K interval. Several changes on the inter and intramolecular vibration bands during the cooling, such as decreasing bands' intensities, the appearance of vibration modes, and discontinuities on the modes' behavior, were observed. These spectral modifications occurred at about 370 K and within 120-220 K, thus, confirming that the crystals undergo two phase changes, one being structural and the other one conformational, respectively, at high- temperature and low-temperature conditions. Finally, thermal investigations corroborated the structural and vibrational results under high temperatures.

RESUMEN

Chloro(glycinato-N,O)(1,10-phenanthroline-N,N')­copper(II) trihydrate complex was synthesized through the slow evaporation method. The crystal's structural, thermal, magnetic, and vibrational properties were obtained by X-ray powder diffraction (XRPD), thermal analyses, magnetization, Raman, and Fourier-transform infrared (FT-IR) spectroscopy. XRPD results showed that the crystalline complex belongs to a monoclinic system (P21/n). Thermal analyses revealed that around 333 K, the material undergoes a thermodynamically irreversible process. Magnetic data showed a paramagnetic behavior with weak ferromagnetic interactions. Moreover, all the Raman- and infrared-active bands were assigned from computational calculations based on the density functional theory (DFT) to analyze intra-molecular vibrational modes. In addition, the cytotoxic assay on colorectal cancer cells was performed to evaluate the antitumor activity of this ternary compound. Therefore, the antineoplastic activity of [Cu(1,10-phenanthroline)(glycine)Cl]•3H2O complex in HCT-116 cells was confirmed, showing a potent cytotoxic effect.

Asunto(s)

Antineoplásicos , Neoplasias Colorrectales , Complejos de Coordinación , Cobre , Citotoxinas , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Cobre/química , Cobre/farmacología , Citotoxinas/química , Citotoxinas/farmacología , Células HCT116 , Humanos , Ratones , Células RAW 264.7

RESUMEN

The association between exposure to air pollutants and respiratory diseases is well known. This study aimed to identify the association between this exposure and hospitalizations for COVID-19 in São José dos Campos, SP, a medium-sized city, between April 2020 and April 2021. Hospitalization data, concerning code B34.2, was supplied by DATASUS, and data concerning pollutants and climate variables were supplied by CETESB. Cases were quantified by sex, age, length of hospital stay in days, and type of discharge, whether hospital discharge or death. The negative binomial regression model was chosen. Estimates were produced for the relative risk (RR) of significant exposure to pollutants (P≤0.05) with a 10 µg/m3 increase of pollutant, as well as for excess hospitalizations. There were 1873 hospitalizations, with a daily average of 4.7 (±3.8), ranging from zero to 21: 716 deaths (38.2%) were recorded, 1065 admissions were men, and women were less susceptible (OR=0.82). The average age of women was higher than that of men; in cases of death, men were older than women; discharged patients were younger. All the above variables were significant. The risk of ozone exposure was higher and more significant in Lag 2, and the risk of nitrogen dioxide exposure was high in Lag 3, which was the period of the highest increase in hospitalizations, at 11.3%. The findings of this study, the first conducted in Brazil, corroborate the results of studies conducted in other centers.

RESUMEN

Constitutional genomic imbalances are known to cause malformations, disabilities, neurodevelopmental delay, and dysmorphia and can lead to dysfunctions in the cell cycle. In extremely rare genetic conditions such as small supernumerary marker chromosomes (sSMC), it is important to understand the cellular consequences of this extra marker, as well the factors that contribute to their maintenance or elimination through successive cell cycles and phenotypic impact. The study of chromosomal mosaicism provides a natural model to characterize the effect of aneuploidy on genome stability and compare cells with the same genetic background and environment exposure, but differing in the presence of sSMC. Here, we report the functional characterization of different cell lines from two familial patients with mosaic sSMC derived from chromosome 12. We performed studies of proliferation dynamics, stability, and variability of these cells using fluorescent in situ hybridization (FISH), sister chromatid exchanges (SCE), and conventional staining. We also quantified the telomere-related genomic instability of sSMC cells using 3D telomeric profile analysis by quantitative-FISH. sSMC cells exhibited differences in the cell cycle dynamics compared to normal cells. First, the sSMC cells exhibited lower proliferation index and higher frequency of SCE than normal cells, associated with a higher level of chromosomal instability. Second, sSMC cells exhibited more telomeric-related genomic instability. Lastly, the differences of sSMC cells distribution among tissues could explain different phenotypic repercussions observed in patients. These results will help in our understanding of the sSMC stability, maintenance during cell cycle, and the cell cycle variables involved in the different phenotypic manifestations.

RESUMEN

A patient was referred, after neoadjuvant chemotherapy, for pre-surgical evaluation of urothelial bladder carcinoma (single lesion). Two thickenings in the left ureter wall identified on the CT scan were equivocal for malignancy. 18F-FDG PET/CT with delayed pelvic images, hyperhydration, and furosemide showed hypermetabolic ureteral metastases and multifocal bladder tumors. There were no lymph nodes or distant metastases. These 18F-FDG PET/CT findings completely altered the surgical treatment. The patient underwent left nephroureterectomy, radical cystoprostatectomy, and lymphadenectomy, followed by a urinary transit reconstruction. Histopathology confirmed multifocal high-grade urothelial carcinoma in the bladder walls and left ureter and benign lymph nodes.

RESUMEN

DL-glutamic acid monohydrate crystal was synthesized from an aqueous solution by slow evaporation technique. The crystal was submitted to high-pressure (1 atm-14.3 GPa) to investigate its vibrational behavior and the occurrence of phase transitions. We performed Raman spectroscopy as probe and through the analysis of the spectra we discovered three structural phase transitions. The first one occurs around 0.9 GPa. In this phase transition, glutamic acid molecules suffer modifications in their conformations while water molecules are less affected. The second phase transition at 4.8 GPa involves conformational changes related to CO2-, NH3+ units and the water molecules, while the third one, between 10.9 and 12.4 GPa, involves motions of several parts of the glutamic acid as well as the water molecules. Considering the dynamic of high pressure, the second phase of DL-glutamic acid monohydrate crystal presented a better stability compared with the second phase of its polymorphs α and ß L-glutamic acid. In addition, water molecules seem to play important role on this structural stability. All changes are reversible.

Asunto(s)

Ácido Glutámico/química , Conformación Molecular , Transición de Fase , Presión , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Espectrometría Raman

RESUMEN

PURPOSE: Patients with stage III non-small-cell lung cancer (NSCLC) treated with chemoradiotherapy (CRT) in low- and middle-income countries (LMIC) continue to have a poor prognosis. It is known that FDG PET/CT improves staging, treatment selection and target volume delineation (TVD), and although its use has grown rapidly, it is still not widely available in LMIC. CRT is often used as sequential treatment, but is known to be more effective when given concurrently. The aim of the PERTAIN study was to assess the impact of introducing FDG PET/CT-guided concurrent CRT, supported by training and quality control (QC), on the overall survival (OS) and progression-free survival (PFS) of patients with stage III NSCLC. METHODS: The study included patients with stage III NSCLC from nine medical centres in seven countries. A retrospective cohort was managed according to local practices between January 2010 and July 2014, which involved only optional diagnostic FDG PET/CT for staging (not for TVD), followed by sequential or concurrent CRT. A prospective cohort between August 2015 and October 2018 was treated according to the study protocol including FDG PET/CT in treatment position for staging and multimodal TVD followed by concurrent CRT by specialists trained in protocol-specific TVD and with TVD QC. Kaplan-Meier analysis was used to assess OS and PFS in the retrospective and prospective cohorts. RESULTS: Guidelines for FDG PET/CT image acquisition and TVD were developed and published. All specialists involved in the PERTAIN study received training between June 2014 and May 2016. The PET/CT scanners used received EARL accreditation. In November 2018 a planned interim analysis was performed including 230 patients in the retrospective cohort with a median follow-up of 14 months and 128 patients in the prospective cohort, of whom 69 had a follow-up of at least 1 year. Using the Kaplan-Meier method, OS was significantly longer in the prospective cohort than in the retrospective cohort (23 vs. 14 months, p = 0.012). In addition, median PFS was significantly longer in the prospective cohort than in the retrospective cohort (17 vs. 11 months, p = 0.012). CONCLUSION: In the PERTAIN study, the preliminary results indicate that introducing FDG PET/CT-guided concurrent CRT for patients with stage III NSCLC in LMIC resulted in a significant improvement in OS and PFS. The final study results based on complete data are expected in 2020.

Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Quimioradioterapia , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Carcinoma de Pulmón de Células no Pequeñas/terapia , Supervivencia sin Enfermedad , Estonia , Femenino , Fluorodesoxiglucosa F18 , Humanos , Procesamiento de Imagen Asistido por Computador , India , Jordania , Estimación de Kaplan-Meier , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Pakistán , Estudios Prospectivos , Control de Calidad , Planificación de la Radioterapia Asistida por Computador , Estudios Retrospectivos , Resultado del Tratamiento , Turquía , Vietnam

RESUMEN

The study of [bis(L­alaninato) diaqua] nickel(II) dihydrate crystal using Raman scattering and X-ray diffraction as a function of temperature is reported in this paper. Thermal analysis (TGA and DSC) complementary measurements were also performed in order to obtain information on structural changes and mass loss occurred in this material. It was identified that the crystal undergoes loss of water at two different temperatures: ~340 and 393 K. X-ray diffraction measurements showed two phase transformations related to these two water loss events. After heating up to 423 K, the sample was cooled down to 298 K and its diffraction pattern presented the same pattern at 423 K, evidencing an irreversible phase transformation. The diffraction results also showed that crystal goes to monohydrate and anhydrous phases. Furthermore, cell lattice parameters and space groups of both phases were determined by applying Rietveld refinement through Le Bail method, demonstrating that their structures belong to the P21 and C2/c space groups, both with monoclinic symmetry. In addition, assignments of Raman spectra vibrational bands (at 300 K) are provided. The high-temperature Raman spectra were obtained in the 100-3500 cm-1 range, where it was observed several abrupt changes in the intensity of low-wavenumber bands and the appearance/disappearance of some vibrational modes that have coupling with OH⋯O hydrogen bonds. These spectral changes are in good agreement with X-ray diffraction and thermal analyses data. Finally, we obtained Raman measurements at low temperatures, from which we identified that the crystal structure is extremely stable throughout the temperature range of 293-10 K.

RESUMEN

In several crops, the water deficit is perhaps the main limiting factor in the search for high yields. The objective of this study was to evaluate the phenotypic stability of maize hybrids in environments with and without water restriction using the analytical factor (AF) approach. We evaluated 171 maize hybrids in 14 environments, divided into environments with (A1, A2, A3, A4, A5, A6, and A7) and without (A8, A9, A10, A11, A12, A13, and A14) water restriction, over a period of 7 years. Each year, 36 hybrids were evaluated. A square lattice design (6 x 6) was used, with common treatments between years. The characteristics of grain yield (GY), male flowering (MF) and female flowering (FF), plant height (PH), and ear height (EH) were evaluated. Phenotypic adaptability and stability of the hybrids were also verified. Hybrids G66, G99, G86, and G26 were the most stable and showed potential for use in environments with and without water restriction. The AF models showed to be useful for evaluating hybrids over many years, allowing selection of better hybrids with adaptability, specific and general stability, and correlation of hybrids with their production components, in addition to allowing identification of mega-environments that permit stability in the response of the adapted hybrids.

Asunto(s)

Inestabilidad Genómica , Hibridación Genética , Fitomejoramiento/métodos , Estrés Fisiológico , Zea mays/genética , Sequías , Ambiente , Modelos Genéticos , Carácter Cuantitativo Heredable , Zea mays/crecimiento & desarrollo

RESUMEN

Single crystal of monoglycine nitrate has been studied by Raman spectroscopy under high pressures up to 5.5 GPa. The results show changes in lattice modes in the pressure ranges of 1.1-1.6 GPa and 4.0-4.6 GPa. The first change occurs with appearance of bands related to the lattice modes as well as discontinuity in the slope of dΩ/dP of these modes. Moreover, bands associated with the skeleton of glycine suggest that the molecule undergoes conformational modifications. The appearance of a strong band at 55 cm(-1) point to a second phase transition associated with the lattice modes, while the internal modes remain unchanged. These anomalies are probably due to rearrangement of hydrogen bonds. Additionally, decompression to ambient pressure shows that the phase transitions are reversible. Finally, the results show that the nitrate anions play an important role on the stability of the monoglycine nitrate crystal.

RESUMEN

AIMS: This study aimed to evaluate the effects of inoculation of strains of lactic acid bacteria (LAB) isolated from sugarcane grown in a Brazil on the quality of corn silage. METHODS AND RESULTS: Three strains of Lactobacillus buchneri (UFLA SLM11, UFLA SLM103 and UFLA SLM108), five strains of Lactobacillus plantarum (UFLA SLM08, UFLA SLM41, UFLA SLM45, UFLA SLM46 and UFLA SLM105), and one strain of Leuconostoc mesenteroides (UFLA SLM06) were evaluated at 0, 10, 30, 60 and 90 day after inoculating corn forage. The inoculation of the LAB strains did not influence the chemical composition of the silage, but pH, acetic acid and 1,2-propanediol were affected by treatment. The silages inoculated with UFLA SLM11 and SLM108 contained the lowest yeast and filamentous fungi counts during fermentation. Bacteria belonging to the Enterobacteriaceae family, Clostridium genus were detected in the silages inoculated with Lact. buchneri UFLA SLM 11, 103 and 108, as shown by DGGE analysis. Silages inoculated with Lact. buchneri UFLA SLM 11 showed higher aerobic stability. CONCLUSIONS: The Lact. buchneri UFLA SLM11 strain was considered promising as a starter culture or inoculant for corn silages. SIGNIFICANCE AND IMPACT OF THE STUDY: The selection of microbial inoculants for each crop promotes improvement of silage quality. Studies on the chemical and microbiological characteristics of silage provide useful information for improving ensiling techniques.

Asunto(s)

Lactobacillaceae/metabolismo , Ensilaje/microbiología , Zea mays/microbiología , Aerobiosis , Biodiversidad , Brasil , Fermentación , Ácido Láctico/análisis , Ácido Láctico/metabolismo , Lactobacillaceae/clasificación , Lactobacillaceae/genética , Lactobacillaceae/aislamiento & purificación , Saccharum/microbiología , Ensilaje/análisis , Zea mays/química

RESUMEN

The objectives of the study were to evaluate the performance of sentinel lymph node biopsy (SLNB) in detecting occult metastases in papillary thyroid carcinoma (PTC) and to correlate their presence to tumor and patient characteristics. Twenty-three clinically node-negative PTC patients (21 females, mean age 48.4 years) were prospectively enrolled. Patients were submitted to sentinel lymph node (SLN) lymphoscintigraphy prior to total thyroidectomy. Ultrasound-guided peritumoral injections of (99m)Tc-phytate (7.4 MBq) were performed. Cervical single-photon emission computed tomography and computed tomography (SPECT/CT) images were acquired 15 min after radiotracer injection and 2 h prior to surgery. Intra-operatively, SLNs were located with a gamma probe and removed along with non-SLNs located in the same neck compartment. Papillary thyroid carcinoma, SLNs and non-SLNs were submitted to histopathology analysis. Sentinel lymph nodes were located in levels: II in 34.7 % of patients; III in 26 %; IV in 30.4 %; V in 4.3 %; VI in 82.6 % and VII in 4.3 %. Metastases in the SLN were noted in seven patients (30.4 %), in non-SLN in three patients (13.1 %), and in the lateral compartments in 20 % of patients. There were significant associations between lymph node (LN) metastases and the presence of angio-lymphatic invasion (p = 0.04), extra-thyroid extension (p = 0.03) and tumor size (p = 0.003). No correlations were noted among LN metastases and patient age, gender, stimulated thyroglobulin levels, positive surgical margins, aggressive histology and multifocal lesions. Sentinel lymph node biopsy can detect occult metastases in PTC. The risk of a metastatic SLN was associated with extra-thyroid extension, larger tumors and angio-lymphatic invasion. This may help guide future neck dissection, patient surveillance and radioiodine therapy doses.

Asunto(s)

Carcinoma/diagnóstico , Carcinoma/secundario , Ganglios Linfáticos/patología , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/secundario , Carcinoma/cirugía , Carcinoma Papilar , Femenino , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Linfocintigrafia , Masculino , Persona de Mediana Edad , Disección del Cuello , Estadificación de Neoplasias , Estudios Prospectivos , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X

Asunto(s)

Humanos , Ética en Investigación , Publicaciones Periódicas como Asunto/ética

RESUMEN

We identified native bees that are floral visitors and potential pollinators of tomato in Cerrado areas, described the foraging behavior of these species, and verified the influence of the visitation of a solitary bee on the quantity and quality of fruits. Three areas of tomato crops, located in Minas Gerais, Brazil, were sampled between March and November 2012. We collected 185 bees belonging to 13 species. Exomalopsis (Exomalopsis) analis Spinola, 1853 (Hymenoptera: Apidae) was the most abundant. Ten species performed buzz pollination. Apis mellifera L. 1758 (Hymenoptera: Apidae) and Paratrigona lineata (Lepeletier, 1836) (Hymenoptera: Apidae) could also act as pollinators. The fruit set and number of seeds obtained from the pollination treatment by E. analis were higher than those in the control group. Our results allowed the identification of potential tomato pollinators in Cerrado areas and also contributed information regarding the impact of a single species (E. analis) on fruit set and quality. Although most of the visiting bees show the ability for tomato pollination, there is an absence of adequate management techniques, and its usage is difficult with the aim of increasing the crop production, which is the case for E. analis. Species such as Melipona quinquefasciata, P. lineata, and A. mellifera, which are easy to handle, are not used for pollination services. Finally, it is suggested that a combination of different bee species that are able to pollinate the tomato is necessary to prevent the super-exploitation of only a single species for pollination services and to guarantee the occurrence of potential pollinators in the crop area.

Asunto(s)

Abejas/fisiología , Polinización , Solanum lycopersicum/fisiología , Animales , Abejas/clasificación , Brasil , Flores/fisiología , Frutas/crecimiento & desarrollo , Solanum lycopersicum/crecimiento & desarrollo

Asunto(s)

Ética en Investigación , Publicaciones Periódicas como Asunto/ética , Humanos