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1.
Int J Neurosci ; : 1-8, 2024 May 28.
Article de Anglais | MEDLINE | ID: mdl-38742394

RÉSUMÉ

OBJECTIVES: This clinical, analytical, retro-prospective, auto-controlled, not randomized, and not blinded study, aimed to investigate the association of changes in the serum glucose levels with the pre-and-post changes in the size tumor in mm3 in the Non-Functional pituitary adenomas. METHODS: Pre-and post-surgical MRI, as well as the measurements in the serum glucose levels and immunohistochemical techniques were performed in all the patients in the study, with a mean followed-up until 208.57 days. A comparison was made between the reductions in tumor size of hormonally active pituitary adenomas (HSPAs) vs NFPAs. RESULTS: Seventy-four patients were included in this study, of whom, 46 were NFPAs. The decrease in the NFPAs tumor size after surgery was statistically significant (P ≤ 0.0001). The Mean of the differences of both type of tumors in mm3 were -9552 ± 10287. Pre-surgery, the mean of the HSPAs were 8.923 ± 2.078; and the NFPAs were 14.161 ± 1.912. The differences in the tumor size were statistically significant (p = 0.039). Post-surgical, the mean of the HSPAs were 2.079 ± 971, with a (p = 0.14): and the NFPAs were 4.609 ± 1.205. After surgery of the NFPAs, most of the patients-maintained serum levels ≤ 100 mg/dL, with a statistical significance (P ≤ 0.0003). CONCLUSION: This study demonstrates for the first time the correlation between the presence of pre-and post- surgical changes in the NFPAs, with modifications in the levels of serum glucose, and the comparison, pre- and post-surgical between the tumor size of HSPAs and NFPAs.

2.
Acta Neurochir (Wien) ; 166(1): 86, 2024 Feb 16.
Article de Anglais | MEDLINE | ID: mdl-38363400

RÉSUMÉ

BACKGROUND: Pituitary adenomas (PA) are neoplasms of pituitary adenohypophyseal cell lineage, which are the third most common cause of brain tumors among adults. Due to hormone secretion, PAs are closely related to metabolic syndrome (MetS). However, the relationship between these two entities has been scarcely studied to date. PURPOSE: This paper aims to evaluate changes in the metabolic status of patients with PA before and after surgical treatment and to look for differences in metabolic outcomes among patients according to the adenoma type and the surgery success rate. METHODS: We assessed patients with PA who went through transsphenoidal surgery for its treatment, documenting metabolic parameters before and after surgery, analyzed whole sample changes, and then stratified them according to adenoma type (nonfunctioning, somatotroph, lactotroph, and corticotroph), and surgery success (total resection, near-total resection, partial resection, subtotal resection). RESULTS: A total of 214 patients were enrolled for this study. The prevalence of MetS with AACE criteria went from 51.52% before surgery to 28.99% after surgery (P < 0.001). Hyperglycemia (HG) was the most beneficial component; it went from 56% pre-surgery to 40.51% post-surgery (P = 0.03). The total resection group had the best improvement, with a significant decrease of prevalence in MetS from 83 to 16% (P < 0.001), and every component, except hypoalphalipoproteinemia (HA): obesity went from 96 to 67% (P < 0.001), arterial hypertension (AH) 59 to 24% (P < 0.001), HG 74 to 23% (P < 0.001), and hypertriglyceridemia (HTG) from 81 to 54% (P < 0.001). According to MetS prevalence, there was no difference in the improvement according to PA type. CONCLUSION: Surgical treatment in patients with PA is associated with MetS improvement.


Sujet(s)
Adénomes , Syndrome métabolique X , Tumeurs de l'hypophyse , Adulte , Humains , Tumeurs de l'hypophyse/chirurgie , Tumeurs de l'hypophyse/anatomopathologie , Syndrome métabolique X/chirurgie , Syndrome métabolique X/étiologie , Procédures de neurochirurgie/effets indésirables , Adénomes/chirurgie , Adénomes/anatomopathologie , Sinus sphénoïdal/chirurgie , Études rétrospectives , Résultat thérapeutique
3.
Expert Rev Hematol ; 16(12): 1143-1149, 2023.
Article de Anglais | MEDLINE | ID: mdl-37955142

RÉSUMÉ

BACKGROUND: Venous thromboembolism (VTE) and major bleeding (MB) are common in cancer patients. Reduced-doses of antithrombotics as secondary prophylaxis have limited data. This work aims to describe and to compare treatments and outcomes for cancer-associated VTE. RESEARCH DESIGN AND METHODS: Retrospective study. Adults with cancer-associated VTE were included. After 3-6 months of full-doses of anticoagulants, three strategies were considered: A) lowering the doses; B) maintaining full-doses; C) stopping treatment. The strategy and medication used were shown in a descriptive analysis and the rate of bleeding and VTE-recurrence between those in a comparative analysis. RESULTS: A total of 420 patients were included, 56.2% received DOACs, 43.8% enoxaparin. Strategy was defined in 257 patients: A (50.2%), B (46.3%), and C (3.5%). Forty-one (9.8%) had VTE-recurrence and 15 (3.6%) had MB or clinically relevant non-major bleeding (CRNMB).According to strategy, recurrent-VTE was 8.5% (A), 4.2% (B), and 11.1 (C) (p = 0.22), MB or CRNMB was 0.8% (A), 1.7% (B), and 0% (C) (p = 0.64). CONCLUSIONS: DOACs and strategy A were the most frequently used agent and strategy, respectively. There were no differences between medications or strategies used. The results must be interpreted with caution, and it is a retrospective single-center study, probably with information and selection bias.


Sujet(s)
Tumeurs , Thromboembolisme veineux , Adulte , Humains , Héparine bas poids moléculaire/effets indésirables , Thromboembolisme veineux/étiologie , Thromboembolisme veineux/complications , Études rétrospectives , Argentine/épidémiologie , Anticoagulants/effets indésirables , Hémorragie/étiologie , Tumeurs/complications , Tumeurs/traitement médicamenteux
4.
Cells ; 12(21)2023 11 04.
Article de Anglais | MEDLINE | ID: mdl-37947651

RÉSUMÉ

Capsaicinoids are a unique chemical species resulting from a particular biosynthesis pathway of hot chilies (Capsicum spp.) that gives rise to 22 analogous compounds, all of which are TRPV1 agonists and, therefore, responsible for the pungency of Capsicum fruits. In addition to their human consumption, numerous ethnopharmacological uses of chili have emerged throughout history. Today, more than 25 years of basic research accredit a multifaceted bioactivity mainly to capsaicin, highlighting its antitumor properties mediated by cytotoxicity and immunological adjuvancy against at least 74 varieties of cancer, while non-cancer cells tend to have greater tolerance. However, despite the progress regarding the understanding of its mechanisms of action, the benefit and safety of capsaicinoids' pharmacological use remain subjects of discussion, since CAP also promotes epithelial-mesenchymal transition, in an ambivalence that has been referred to as "the double-edge sword". Here, we update the comparative discussion of relevant reports about capsaicinoids' bioactivity in a plethora of experimental models of cancer in terms of selectivity, efficacy, and safety. Through an integration of the underlying mechanisms, as well as inherent aspects of cancer biology, we propose mechanistic models regarding the dichotomy of their effects. Finally, we discuss a selection of in vivo evidence concerning capsaicinoids' immunomodulatory properties against cancer.


Sujet(s)
Capsicum , Tumeurs , Humains , Capsaïcine/pharmacologie , Fruit/métabolisme , Tumeurs/traitement médicamenteux , Tumeurs/métabolisme , Biologie
6.
Trop Biomed ; 40(2): 183-187, 2023 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-37650405

RÉSUMÉ

This study analysed the mechanisms of quinolone resistance among enterotoxigenic Escherichia coli (ETEC) in a periurban area of Lima, Peru. The susceptibility to nalidixic acid and ciprofloxacin, the role of Phe-Arg-b-Naphtylamyde inhibitable-(PAbN) efflux pumps, the presence of mutations in gyrA and parC as well as the presence of aac(6')Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD, qnrVC and oqxAB were determined in 31 ETEC from previous case/control studies of children's diarrhoea. Discordances between disk diffusion, with all isolates showing intermediate or fully resistance to nalidixic acid, and minimal inhibitory concentration (MIC), with 7 isolates being below considered resistance breakpoint, were observed. Twenty-one isolates possessed gyrA mutations (19 S83L, 2 S83A). AAC(6') Ib-cr, QnrS, QnrB and QepA were found in 7, 6, 2 and 1 isolates respectively, with 3 isolates presenting 2 transferable mechanisms of quinolone resistance (TMQR) concomitantly. TMQR were more frequent among isolates with MIC to nalidixic acid ranging from 2 to 16 mg/L (p=0.03), while gyrA mutations were more frequent among isolates with nalidixic acid MIC >= 128 mg/L (p=0.0002). In summary, the mechanisms of quinolone resistance present in ETEC isolates in Peru have been described. Differences in the prevalence of underlying mechanisms associated with final MIC levels were observed. The results suggest two different evolutive strategies to survive in the presence of quinolones related to specific bacterial genetic background.


Sujet(s)
Escherichia coli entérotoxigène , Quinolinone , Enfant , Humains , Escherichia coli entérotoxigène/génétique , Acide nalidixique/pharmacologie , Quinolinone/pharmacologie , Ciprofloxacine , Études cas-témoins
7.
Arch Soc Esp Oftalmol ; 98(5): 259-264, 2023 May.
Article de Espagnol | MEDLINE | ID: mdl-37122609

RÉSUMÉ

Introduction and objectives: Although the ophthalmic manifestations appear to be associated with the coronavirus disease 2019 (COVID-19), there is not enough evidence. Hence, the aim of this study was to determine the various types and frequency of ophthalmic manifestations in patients recovered from SARS-CoV-2 infection in Mexico. Material and methods: This retrospective, observational and descriptive study included all patients recovered from SARS-CoV-2 infection attending the tertiary level hospital of Mexican Social Security Institute (IMSS) from June 2020 to June 2022. During the hospital admission of patients, the demographic data such age, name, gender was recorded. Ophthalmologic examination was performed under torchlight by an ophthalmologist in the Department of Ophthalmology from IMSS. Data was compiled and statistically analyzed using Fisher's exact test and Spearman correlation. Results: A total of 3,081 SARS-CoV-2-positive patients were recorded, of which 318 (10.32%) met the inclusion criteria. Of them, 21 (6.60%) had ophthalmic manifestations and the female-to-male ratio was 1.6:1. The mean age (±SD) was 47.95 ± 15.27 years and the median (interquartile range) time from the diagnosis of COVID-19, as defined by positive SARS-CoV-2 RT-PCR testing, to detection of the ophthalmic manifestation was 31 (142) days. The most common ocular manifestation was orbital mucormycosis (23.80%). Interestingly, the presence of ophthalmic manifestations was not associated with severe COVID-19 (p = 0.665). Conclusions: The ophthalmic manifestations are infrequent in patients recovered from severe COVID-19. Nevertheless, further large sample studies are needed to confirm these findings.

8.
Int J Neurosci ; : 1-10, 2023 Apr 29.
Article de Anglais | MEDLINE | ID: mdl-37060337

RÉSUMÉ

BACKGROUND: Pituitary adenomas are benign tumors located in the anterior hypophysis. Its appearance is associated with the development of parameters related to metabolic syndrome; therefore, surgical treatment could reduce associated morbimortality. METHODS: Pre- and post-surgical MRI, using the Hardy-Wilson and Knosp classification, and clinical data according to the American Association of Clinical Endocrinology (AACE) criteria for metabolic syndrome: all the patients were followed-up until 208.57 days were reviewed on 217 consecutive patients with pituitary surgery. RESULTS: Seventy-four patients were included in this study. There was a significant reduction in tumor size in mm3 [average pre- and post-surgery respectively: 12,362 mm3 (±12,397); 3,910 mm3 (±7,160)], (p < 0.0001). This was confirmed by the Hardy-Wilson and Knosp classification, where most patients went from grade IV C (33.7%) to grade 0 (12.1%), IA (20.2%), IIB (21.36%), and IIC (16.2%); as well as from grade 4 (24.3%) to grade 0 (45.9%), respectively. After surgery, there were statistically significant reductions in total serum levels of glucose [average pre- and post-surgery, respectively: 116 mg/dL (±26.9); 90 mg/dL (±10.2)], (p < 0.001), triglycerides [average pre- and post-surgery, 240 mg/dL (±102); 171 mg/dL (±60.5)], (p = 0.001); and HDL-c [average pre- and post-surgery, respectively: 39 mg/dL (±11.8); 44.6 mg/dL (±8.4)], (p = 0.029). The other parameters remained unchanged. CONCLUSION: This is the first study to demonstrate the relationship between the presence of pituitary adenoma and significative changes in serum glucose, triglycerides and c-HDL related to metabolic syndrome.

9.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(5): 259-264, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-37080429

RÉSUMÉ

INTRODUCTION AND OBJECTIVES: Although the ophthalmic manifestations appear to be associated with the coronavirus disease 2019 (COVID-19), there is not enough evidence. Hence, the aim of this study was to determine the various types and frequency of ophthalmic manifestations in patients recovered from SARS-CoV-2 infection in Mexico. MATERIAL AND METHODS: This retrospective, observational and descriptive study included all patients recovered from SARS-CoV-2 infection attending the tertiary level hospital of Mexican Social Security Institute (IMSS) from June 2020 to June 2022. During the hospital admission of patients, the demographic data such age, name, gender was recorded. Ophthalmologic examination was performed under torchlight by an ophthalmologist in the Department of Ophthalmology from IMSS. Data was compiled and statistically analyzed using Fisher's exact test and Spearman correlation. RESULTS: A total of 3081 SARS-CoV-2-positive patients were recorded, of which 318 (10.32%) met the inclusion criteria. Of them, 21 (6.60%) had ophthalmic manifestations and the female-to-male ratio was 1.6:1. The mean age (±SD) was 47.95±15.27 years and the median (interquartile range) time from the diagnosis of COVID-19, as defined by positive SARS-CoV-2 RT-PCR testing, to detection of the ophthalmic manifestation was 31 (142) days. The most common ocular manifestation was orbital mucormycosis (23.80%). Interestingly, the presence of ophthalmic manifestations was not associated with severe COVID-19 (p=0.665). CONCLUSIONS: The ophthalmic manifestations are infrequent in patients recovered from severe COVID-19. Nevertheless, further large sample studies are needed to confirm these findings.


Sujet(s)
COVID-19 , Maladies de l'oeil , Humains , Mâle , Femelle , Nourrisson , COVID-19/complications , SARS-CoV-2 , Études rétrospectives , Mexique/épidémiologie
10.
Rev. bras. ciênc. avic ; 25(1): eRBCA-2022-1663, 2023. graf, tab
Article de Anglais | VETINDEX | ID: biblio-1416241

RÉSUMÉ

The objective of this study was to evaluate the effect of the seasons (Summer and Autumn), on live weight, body condition, mass motility, percentage of live spermatozoa, and sperm-cell concentration of Creole roosters (Gallus domesticus) from Mexico. Semen from 35-week-old Creole roosters was collected weekly during 10 weeks in Summer and Autumn, through the dorso-abdominal massage technique. Roosters were individually kept under a constant photoperiod (16 hours light:8 hours dark). The average live weight was 4.5% higher (p<0.05) in Autumn (2.78 kg) than in Summer (2.66 kg), therefore this variable increased with age (r = 0.85, p<0.05). Category 2 of body condition occurred (p<0.05) with higher probability than the others (0, 1 and 3), being practically the same (p>0.05) in Autumn (99.96%) and in Summer (99.81%). On average (and in weeks 1 and 3-10), the percentage of live spermatozoa was higher in Summer than in Autumn. Accordingly, the percentage of live spermatozoa decreased with age (r = -0.82, p<0.05). However, on average, sperm-cell concentration did not change between seasons (p>0.05). In conclusion, Mexican Creole roosters showed higher percentage of live spermatozoa in Summer than in Autumn. Therefore, it is advisable to select these animals of about 2.7 kg and reproduce them in Summer.(AU)


Sujet(s)
Animaux , Mâle , Sperme/composition chimique , Poulets/physiologie , Analyse du sperme/médecine vétérinaire , Saisons , Composition corporelle , Phénomènes physiques , Mexique
11.
Vaccine ; 40(49): 7042-7049, 2022 11 22.
Article de Anglais | MEDLINE | ID: mdl-36272874

RÉSUMÉ

In Argentina, vaccines included in the national calendar are mandatory, free of charge, and access to vaccination services with social equity for all stages of life are guaranteed by law. However, vaccination coverages are still suboptimal and have shown a constant decrease in the last five years. This study aimed to perform a survey to describe the parent's confidence, risk perception, sources of information and access barriers to vaccines and vaccination in Argentina. A survey was designed for parents in charge of children under 12 years of age to answer. The questionnaire was constructed based on validated questions of the international peer-reviewed literature adapted to our country's characteristics. The survey was performed on 1,202 respondents, covering all regions of Argentina, between 19th May and 18th June 2020. To highlight, 76.6 % were female and the mean age was 40.72 (±9.36 years). 9 % participants reported to assist to the private vaccination center, while 64 % and 23 % referred to take their children to the public vaccination point (primary care center and hospital, respectively). Additionally, respondents agreed that vaccines are safe (92 %), effective (94 %), and important for children to receive them (98 %). 48 % could identify-one or more barriers to vaccination, access and affordability were the most reported ones (74 %) being the lack of vaccine the main reason. In conclusion, this study showed that the great majority of parents trust in vaccines and health care teams but access and affordability reasons emerged as the main barriers to vaccination in our country.


Sujet(s)
Connaissances, attitudes et pratiques en santé , Vaccins , Enfant , Humains , Femelle , Adulte , Mâle , Argentine , Vaccination , Parents , Enquêtes et questionnaires
12.
Appl Radiat Isot ; 186: 110268, 2022 Aug.
Article de Anglais | MEDLINE | ID: mdl-35550227

RÉSUMÉ

The increasing use of thermoluminescence (TL) materials as radiation detectors with application in different areas of ionizing radiation has motivated research on new materials with adequate luminescent characteristics. In this work, experimental results gadolinium aluminate (GdAlO3) analyzed by thermoluminescent phenomenon under beta irradiation effect are studied. To prepare GdAlO3 powders the coprecipitation method was used. TL glow curve and other luminescent characteristics were analyzed using an automatic Lexsig Smart TL/OSL luminescent reader. TL glow curve showed four peaks with three prominent and well-defined peaks centered at 140, 230, and 270 °C. TL response as a function of beta radiation dose was linearity in the range from 1.1 up to 44 Gy. Kinetic parameters such as activation energy (E), frequency factor (s), and order of kinetics after the deconvolution of the TL glow curve were also determined using Chen's peak shape method. Experimental results show GdAlO3 as a potential luminescent host material for TL studies.


Sujet(s)
Mesures de luminescence , Dosimétrie par thermoluminescence , Cinétique , Luminescence , Poudres , Dosimétrie par thermoluminescence/méthodes
13.
Neurosurg Rev ; 45(1): 411-419, 2022 Feb.
Article de Anglais | MEDLINE | ID: mdl-34142268

RÉSUMÉ

Brachial plexus injury is a lesion that results in loss of function of the arm, and there are multiple ways of surgically approaching its treatment. Controlled trials that compare all surgical repair strategies and their clinical outcomes have not been performed. A systematic review was conducted to identify all articles that reported clinical outcomes in different surgeries (nerve transfer, nerve graft, neurolysis, end-to-end, multiple interventions, and others). Advanced search in PubMed was performed using the Mesh terms "brachial plexus injury" as the main topic and "surgery" as a subtopic, obtaining a total of 2153 articles. The clinical data for eligibility extraction was focused on collecting motor, sensory, pain, and functional recovery. A statistical analysis was performed to find the superior surgical techniques in terms of motor recovery, through the assessment of heterogeneity between groups, and of relationships between surgery and motor recovery. The frequency and the manner in which clinical outcomes are recording were described. The differences that correspond to the demographics and procedural factors were not statistically significant among groups (p > 0.05). Neurolysis showed the highest proportion of motor recovery (85.18%), with significant results between preoperative and post-operative motor assessment (p = 0.028). The proportion of motor recovery in each group according to the surgical approach differed significantly (X2 = 82.495, p = 0.0001). The motor outcome was the most reported clinical outcome (97.56%), whereas the other clinical outcomes were reported in less than 15% of the included articles. Unexpectedly, neurolysis, a technique displaced by new surgical alternatives such as nerve transfer/graft, demonstrated the highest proportion of motor recovery. Clinical outcomes such as pain, sensory, and functional recovery were infrequently reported. These results introduce the need to re-evaluate neurolysis through comparative clinical trials, as well as to standardize the way in which clinical outcomes are reported.


Sujet(s)
Neuropathies du plexus brachial , Plexus brachial , Transfert nerveux , Plexus brachial/chirurgie , Neuropathies du plexus brachial/chirurgie , Humains , Procédures de neurochirurgie , Résultat thérapeutique
14.
Rehabilitacion (Madr) ; 56(3): 237-242, 2022.
Article de Espagnol | MEDLINE | ID: mdl-33832757

RÉSUMÉ

Unilateral Transtibial Amputees (UTA) usually present deficiencies in the mechanisms underlying their gait likely because of the absence of the resected segment, thus having an impact on the ability to actively adjust the lower limb prosthesis. Five participants with UTA were evaluated considering the ground reaction forces during gait by using an integrated BTS GAITLAB system. The first and the second vertical peak forces tended to be greater in the Healthy Lower Limb (HLL) than in the Lower Limb prosthesis (LLP). Both the deceleration and propulsion forces were lower in this limb prosthesis, in addition, a variability of the mediolateral force was observed. Maintaining active control of the center of gravity during gait from the HLL was probably due to mechanical restrictions to actively control the ankle and the limitations for force absorption and generation that allow controlling postural stability during gait from the LLP.


Sujet(s)
Amputés , Membres artificiels , Amputation chirurgicale , Phénomènes biomécaniques , Démarche , Humains
15.
Sci Rep ; 11(1): 23078, 2021 Nov 29.
Article de Anglais | MEDLINE | ID: mdl-34845293

RÉSUMÉ

Dehydration of the oceanic subducting slab promotes the formation of magmatic arcs, intra-slab intermediate-depth seismicity, and hydration of the overlying mantle wedge. However, the complex permeability structure of the overriding plate controls the magma and fluid migration and their accumulation at shallower depths. In this regard, mapping the inner structure of the overriding crust and mantle is crucial to understand the magmatic and hydrological processes in subduction zones. We integrate 3-D P-wave, [Formula: see text], and electrical resistivity tomographic models of the northern Chilean subduction zone to map the magmatic and fluids derived from the subducting oceanic Nazca plate. Results show a continental crust relatively thick (50-65 km) characterized by a lower zone of high [Formula: see text] values (7.2-7.6 km/s), which is interpreted as the presence of plutonic rocks. The mantle lithospheric wedge is weakly hydrated ([Formula: see text] = 1.75-1.8) while the forearc continental crust is traversed by regions of reduced electrical resistivity values ([Formula: see text] [Formula: see text]) interpreted as zones of relatively high permeability/fracturing and fluid content. These regions spatially correlate with upper plate trans-lithospheric deformation zones. Ascending melts accumulate preferentially in the back-arc, whereas hydrothermal systems form trenchward of the volcanic arc. The results highlight the complex permeability structure of the upper South American plate.

16.
Braz. J. Biol. ; 81(3): 611-620, July-Sept. 2021. tab, ilus, graf
Article de Anglais | VETINDEX | ID: vti-762654

RÉSUMÉ

The present study analyzed the volatile compounds emitted by Glycine max (cv. FT-Cristalina-RCH) soybean plants: healthy plants and plants damaged mechanically or by the Mexican soybean weevil Rhyssomatus nigerrimus. The SPME method was used to compare the volatile profile of soybean plants in four different conditions. The volatile profile of G. max plants infested by R. nigerrimus was qualitatively and quantitatively different from that of healthy and mechanically damaged plants. Emission of 59 compounds was detected in the four treatments. Of these compounds, 19 were identified by comparison of the Kovats index, mass spectrum and retention times with those of synthetic standards. An increase in concentration of the volatiles (Z)-3-hexenyl acetate and the compound 1-octen-3-ol was observed when the soybean plants were mechanically damaged. The compounds mostly produced by the soybean plant during infestation by male and female R. nigerrimus were 1-octen-3-ol, 6-methyl-5-hepten-2-one, (E)-beta-ocimene, salicylaldehyde, unknown 10, linalool, methyl salicylate, (Z)-8-dodecenyl acetate (ester 5), ketone 2 and geranyl acetone. Behavioral effects of the identified compounds during the insect-plant interaction and their conspecifics are discussed.(AU)


O presente estudo analisou os compostos voláteis emitidos pelas plantas de soja Glycine max (cv. FT-Cristalina-RCH): plantas e plantas sadias danificadas mecanicamente ou pelo gorgulho da soja mexicana Rhyssomatus nigerrimus. O método SPME foi utilizado para comparar o perfil volátil de plantas de soja em quatro diferentes condições. O perfil volátil das plantas de G. max infestadas por R. nigerrimus foi qualitativa e quantitativamente diferente do das plantas saudáveis e danificadas mecanicamente. Foi detectada, nos quatro tratamentos, emissão de 59 compostos, dos quais 19 foram identificados por comparação do índice de Kovats, espectro de massa e tempos de retenção com aqueles de padrões sintéticos. Um aumento na concentração dos voláteis acetato de (Z)-3-hexil e do composto 1-octeno-3-ol foi observado quando as plantas de soja foram mecanicamente danificadas. Os compostos produzidos principalmente pela planta de soja durante a infestação por R. nigerrimus macho e fêmea foram 1-octeno-3-ol, 6-metil-5-hepteno-2-ona, (E)-beta-ocimeno, salicilaldeído, desconhecido 10, linalol, salicilato de metila, acetato de (Z)-8-dodecenila (éster 5), cetona 2 e geranil acetona. Foram discutidos os efeitos comportamentais dos compostos identificados durante a interação inseto-planta e seus coespecíficos.(AU)


Sujet(s)
Glycine max/parasitologie , Parasites Agricoles , Charançons , Composés organiques volatils
17.
Braz. j. biol ; Braz. j. biol;81(3): 611-620, July-Sept. 2021. tab, graf
Article de Anglais | LILACS | ID: biblio-1153383

RÉSUMÉ

Abstract The present study analyzed the volatile compounds emitted by Glycine max (cv. FT-Cristalina-RCH) soybean plants: healthy plants and plants damaged mechanically or by the Mexican soybean weevil Rhyssomatus nigerrimus. The SPME method was used to compare the volatile profile of soybean plants in four different conditions. The volatile profile of G. max plants infested by R. nigerrimus was qualitatively and quantitatively different from that of healthy and mechanically damaged plants. Emission of 59 compounds was detected in the four treatments. Of these compounds, 19 were identified by comparison of the Kovats index, mass spectrum and retention times with those of synthetic standards. An increase in concentration of the volatiles (Z)-3-hexenyl acetate and the compound 1-octen-3-ol was observed when the soybean plants were mechanically damaged. The compounds mostly produced by the soybean plant during infestation by male and female R. nigerrimus were 1-octen-3-ol, 6-methyl-5-hepten-2-one, (E)-β-ocimene, salicylaldehyde, unknown 10, linalool, methyl salicylate, (Z)-8-dodecenyl acetate (ester 5), ketone 2 and geranyl acetone. Behavioral effects of the identified compounds during the insect-plant interaction and their conspecifics are discussed.


Resumo O presente estudo analisou os compostos voláteis emitidos pelas plantas de soja Glycine max (cv. FT-Cristalina-RCH): plantas e plantas sadias danificadas mecanicamente ou pelo gorgulho da soja mexicana Rhyssomatus nigerrimus. O método SPME foi utilizado para comparar o perfil volátil de plantas de soja em quatro diferentes condições. O perfil volátil das plantas de G. max infestadas por R. nigerrimus foi qualitativa e quantitativamente diferente do das plantas saudáveis e danificadas mecanicamente. Foi detectada, nos quatro tratamentos, emissão de 59 compostos, dos quais 19 foram identificados por comparação do índice de Kovats, espectro de massa e tempos de retenção com aqueles de padrões sintéticos. Um aumento na concentração dos voláteis acetato de (Z)-3-hexil e do composto 1-octeno-3-ol foi observado quando as plantas de soja foram mecanicamente danificadas. Os compostos produzidos principalmente pela planta de soja durante a infestação por R. nigerrimus macho e fêmea foram 1-octeno-3-ol, 6-metil-5-hepteno-2-ona, (E)-β-ocimeno, salicilaldeído, desconhecido 10, linalol, salicilato de metila, acetato de (Z)-8-dodecenila (éster 5), cetona 2 e geranil acetona. Foram discutidos os efeitos comportamentais dos compostos identificados durante a interação inseto-planta e seus coespecíficos.


Sujet(s)
Animaux , Mâle , Femelle , Charançons , Glycine max
18.
Bioprocess Biosyst Eng ; 44(7): 1525-1538, 2021 Jul.
Article de Anglais | MEDLINE | ID: mdl-33860372

RÉSUMÉ

A biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. A mathematical model was proposed and validated to evaluate the respirometry trends at laboratory and pilot scale exhibiting similar behavior. The cell viability was (1.3 ± 0.4) × 109 and (1.3 ± 0.3) × 109 colony-forming units per gram of initial dry mass at laboratory and pilot scale, at 36 and 43 h, respectively. A. brasilense maintains its viability twelve months of storage at 4 and 30 °C. This is the first report of A. brasilense being cultivated in SSC under controlled conditions. SSC processes involving unicellular microorganisms with tolerance to agitation are a promising technology to produce biofertilizers.


Sujet(s)
Azospirillum brasilense/métabolisme , Bioréacteurs , Biotechnologie/méthodes , Glycérol/composition chimique , Microbiologie industrielle/méthodes , Fermentation , Engrais , Concentration en ions d'hydrogène , Cinétique , Laboratoires , Microscopie électronique à balayage , Modèles théoriques , Consommation d'oxygène , Cellules souches
19.
Braz J Biol ; 81(3): 611-620, 2021.
Article de Anglais | MEDLINE | ID: mdl-32935818

RÉSUMÉ

The present study analyzed the volatile compounds emitted by Glycine max (cv. FT-Cristalina-RCH) soybean plants: healthy plants and plants damaged mechanically or by the Mexican soybean weevil Rhyssomatus nigerrimus. The SPME method was used to compare the volatile profile of soybean plants in four different conditions. The volatile profile of G. max plants infested by R. nigerrimus was qualitatively and quantitatively different from that of healthy and mechanically damaged plants. Emission of 59 compounds was detected in the four treatments. Of these compounds, 19 were identified by comparison of the Kovats index, mass spectrum and retention times with those of synthetic standards. An increase in concentration of the volatiles (Z)-3-hexenyl acetate and the compound 1-octen-3-ol was observed when the soybean plants were mechanically damaged. The compounds mostly produced by the soybean plant during infestation by male and female R. nigerrimus were 1-octen-3-ol, 6-methyl-5-hepten-2-one, (E)-ß-ocimene, salicylaldehyde, unknown 10, linalool, methyl salicylate, (Z)-8-dodecenyl acetate (ester 5), ketone 2 and geranyl acetone. Behavioral effects of the identified compounds during the insect-plant interaction and their conspecifics are discussed.


Sujet(s)
Charançons , Animaux , Femelle , Mâle , Glycine max
20.
Chaos ; 30(12): 123138, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-33380010

RÉSUMÉ

The brain is a biophysical system subject to information flows that may be thought of as a many-body architecture with a spatiotemporal dynamics described by its neuronal structures. The oscillatory nature of brain activity allows these structures (nodes) to be described as a set of coupled oscillators forming a network where the node dynamics and that of the network topology can be studied. Quantifying its dynamics at various scales is an issue that claims to be explored for several brain activities, e.g., activity at rest. The resting-state (RS) associates the underlying brain dynamics of healthy subjects that are not actively compromised with sensory or cognitive processes. Studying its dynamics is highly non-trivial but opens the door to understand the general principles of brain functioning, as well as to contrast a passive null condition vs the dynamics of pathologies or non-resting activities. Here, we hypothesize about how the spatiotemporal dynamics of cortical fluctuations could be for healthy subjects at RS. To do that, we retrieve the alphabet that reconstructs the dynamics (entropy-complexity) of magnetoencephalography (MEG) signals. We assemble the cortical connectivity to elicit the dynamics in the network topology. We depict an order relation between entropy and complexity for frequency bands that is ubiquitous for different temporal scales. We unveiled that the posterior cortex conglomerates nodes with both stronger dynamics and high clustering for α band. The existence of an order relation between dynamic properties suggests an emergent phenomenon characteristic of each band. Interestingly, we find the posterior cortex as a domain of dual character that plays a cardinal role in both the dynamics and structure regarding the activity at rest. To the best of our knowledge, this is the first study with MEG involving information theory and network science to better understand the dynamics and structure of brain activity at rest for different bands and scales.


Sujet(s)
Encéphale , Magnétoencéphalographie , Cartographie cérébrale , Humains , Théorie de l'information , Neurones
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