Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 270
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Plant Dis ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268178

RESUMO

Roselle (Hibiscus sabdariffa L.) is a crop of economic importance, refreshing drinks are prepared from its calyces, it is also attributed to antioxidant, antibacterial, and antihypertensive properties (Da-Costa-Rocha et al. 2014). In November 2022, in municipality of Iguala (18.355592N, 99.548546W, 749 m above sea level), Guerrero, México, roselle plants of approximately 1.5 months of age with basal rot were detected under greenhouse conditions. The symptoms consisted of wilting, yellowing, and root and stem rot with constriction in the base of the stem. The symptoms were detected in approximately 15% of plants at the operation. From symptomatic tissue, cuts were made into approximately 0.5 cm pieces, sterilized with 2% NaClO, washed with sterile distilled water, transferred to PDA medium amended with 50 mg/liter of Chloramphenicol, and incubated in the dark for four days at 28 °C. Rhizoctonia-like colonies were consistently obtained, and nine isolates were selected and purified by the hyphal-tip method. After four days, isolates developed a mycelium was light-white that became brown with age. Right-angled hyphal branching was also observed, in addition to a slight constriction at the base of the branches. In some older cultures, numerous dark brown sclerotia were observed. They were multinucleate cell with three to eight nuclei and measured from 1 to 2 mm in diameter. Together these characteristics were consistent with the description of Rhizoctonia solani Kühn (Parmeter 1970). The anastomosis group (AG) was confirmed by amplifying the ITS region with the primers ITS1 and ITS4 (White et al. 1990) of the RIJAM3 and RIJAM5 strains. The sequences were deposited in GenBank (Nos. OR364496 and OR364497 for RIJAM3 and RIJAM5, respectively). BLAST analysis, both isolates indicated 99.7 identity to R. solani AG-4 HG-I (GenBank: KM013470) strain ICMP 20043 (Ireland et al. 2015). The phylogenetic analysis of AGs sequences allowed assignment of isolates RIJAM3 and RIJAM5 to the AG-4 HG-1 clade. A pathogenicity test was performed on 20 one-month-old roselle plants. Mycelium of RIJAM3 isolate was inserted into the base of the stem with a sterile toothpick. As a control, a sterile toothpick with no mycelium was inserted in ten healthy plants. Additionally, 50 eight-day-old seedlings were inoculated by placing a 5-mm diameter agar plug colonized with mycelium of RIJAM3 at the base of the stem 10 mm below the soil surface. As control treatments, uncolonized PDA plugs were deposited at the base of 25 seedlings. The inoculated plants were incubated in a greenhouse with an average temperature and relative humidity of 28°C and 85%, respectively. Following inoculation, symptoms similar to those observed in the original outbreak were observed in plants after six days and only after four days in seedlings. In both experiments, the control plants and seedlings remained asymptomatic. R. solani was re-isolated from plants and seedlings, complying with Koch's postulates. The pathogenicity testing was repeated twice, with concordant results. In Nigeria and Malaysia R. solani was reported to seedling death to cause seedling dieback in roselle (Adeniji 1970; Eslaminejad and Zakaria 2011). In México R. solani AG-4 has been previously reported in crops of potato, chili and tomato (Montero-Tavera et al. 2013; Ortega-Acosta et al. 2022; Virgen-Calleros et al. 2000). To the best of our knowledge, this is the first report of R. solani AG-4 HG-I as a causing of root and basal stem rot on roselle in Mexico. This research provides information essential for informing the management of this disease, and may help design measures to prevent the spread of the pathogen to other regions.

2.
Ecol Lett ; 26(6): 919-928, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37006190

RESUMO

Pest outbreaks, harmful algal blooms and population collapses are extreme events with critical consequences for ecosystems. Therefore, understanding the ecological mechanisms underlying these extreme events is crucial. We evaluated theoretical predictions on the size scaling and variance of extreme population abundance by combining (i) the generalized extreme value (GEV) theory and (ii) the resource-limited metabolic restriction hypothesis for population abundance. Using the phytoplankton data from the L4 station in the English Channel, we showed a negative size scaling of the expected value of maximal density, whose confidence interval included the predicted metabolic scaling (α = -1) supporting theoretical predictions. The role of resources and temperature in the distribution of the size-abundance pattern and residuals was well characterized by the GEV distribution. This comprehensive modelling framework will allow to elucidate community structure and fluctuations and provide unbiased return times estimates, thereby improving the prediction accuracy of the timing of the population outbreaks.


Assuntos
Ecossistema , Fitoplâncton , Densidade Demográfica , Tamanho Corporal , Temperatura
3.
Plant Dis ; 2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37272039

RESUMO

The guava (Psidium guajava L.) is a plant native to the tropical region of America. In Mexico, the area established with guava cultivation is 20,525 ha (SIAP 2021). Guava is commonly consumed as fresh fruit, being rich in nutrients such as vitamins and minerals (Murthy et al. 2020). During October 2020, in the municipality of Cocula (18.207835N, 99.670322W, 595 m above sea level), Guerrero, Mexico, severely infected immature guava fruits were observed. The incidence of disease in 150 sampled fruits was 12%. Were collected fifteen symptomatic fruits. The symptoms were circular to irregular dark brown spots that varied in size (0.5 to 2.5 cm). From symptomatic fruits, tissues were cut approximately 3 x 3 mm and disinfested with 1% NaOCl, washed three times with sterile distilled water, and transferred to PDA medium amended with streptomycin and tetracycline, and incubated at 28°C. Developing colonies were retransferred to new culture PDA medium, and purified by hyphal tip technique. Two representative isolates (PHYGUA7 and PHYGUA3) were selected for morphological and molecular characterization. After 15 days in PDA at 28°C in an incubator, colonies were flat, irregular, granular and greenish gray, pycnidia were black, granular, and grouped. The conidia were hyaline and ellipsoid, unicellular and smooth-walled, 7-11×5-6.5 µm (n=50), these characteristics were consistent with those described for the fungus Phyllosticta capitalensis (Wikee et al. 2013). Molecular identification was performed by partially sequencing the internal transcribed spacer gene (ITS), the actin gene (ACT), and the translation elongation factor 1-alpha (EF-1α) gene, using primers ITS1 and ITS4, ACT-512F/ ACT-783R, and EF1-728F/EF1-986R, respectively (White et al. 1990; Carbone and Kohn 1999). The resulting sequences were deposited in GenBank (PHYGUA7: OP810947, PHYGUA3: OP810948 for ITS, PHYGUA7: OP819845, PHYGUA3: OP819846 for ACT, and PHYGUA7: OP819847, PHYGUA3: OP819848 for EF-1α). Phylogenetic analysis using maximum likelihood concatenated sequences ITS, ACT and EF-1α with MEGA X, indicated that PHYGUA7 and PHYGUA3 isolated grouped with P. capitalensis (CPC 18848 type strain). For pathogenicity test of P. capitalensis, 15 healthy immature fruits in a field experiment in the fruits on the trees, and 15 healthy mature guava fruits (detached fruits) were superficially disinfected with 70% ethanol, wounded with a sterile toothpick, and inoculated at two equidistant points by inserting PHYGUA7 isolate mycelium. As a control treatment, 10 healthy immature fruits and 10 healthy mature fruits were only injured with a sterile toothpick. After 3 days symptoms were observed in mature fruits and numerous dark pycnidia developed, and seven days later symptoms were observed in immature fruits in all the points inoculated with the PHYGUA7 isolate, similar to the symptoms observed in the field. The control fruits remained asymptomatic. The fungus P. capitalensis was re-isolated from inoculated fruits, thus confirming Koch's postulates. In Mexico P. capitalensis has been reported in Mangifera indica, Epidendrum sp., and Schomburgkia tibicinis (Farr and Rossman, 2022). In Egypt and China P. capitalensis causes black spot on guava fruits (Arafat 2016; Liao et al. 2020). To our knowledge, this is the first report of P. capitalensis as the cause of brown spot on immature guava fruit in Mexico. This research provides relevant information to the design of disease management strategies.

4.
HIV Med ; 22(8): 682-689, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33998115

RESUMO

OBJECTIVES: The aim of the study was to investigate the dynamics of cytomegalovirus (CMV) replication and CMV-specific immune response recovery after antiretroviral treatment (ART) initiation in patients with advanced HIV infection. METHODS: A prospective observational study of patients with HIV infection and CD4 counts of < 100 cells/µL was carried out (September 2015 to July 2018). HIV viral load (VL), CD4 count and CMV VL were determined by quantitative polymerase chain reaction (PCR) at baseline and at 4, 12, 24 and 48 weeks, and CMV-specific immune response was determined by QuantiFERON-CMV assay at baseline and 48 weeks. All patients were started on ART but only those with CMV end-organ disease (EOD) received anti-CMV treatment. RESULTS: Fifty-three patients with a median age of 43.6 [interquartile range (IQR) 36.7-52.4] years were included in the study. At baseline, the median CD4 count was 30 cells/µL (IQR 20-60 cells/µL) and the median HIV VL was 462 000 HIV-1 RNA copies/mL (IQR 186 000-1 300 000 copies/mL). At baseline, 32% patients had detectable CMV viraemia but none had detectable CMV viraemia at 48 weeks. Only one of 53 (1.9%) patients developed EOD during follow-up. Seven (13.2%) patients were lost to follow-up and six (11.3%) died; none of the deaths was related to CMV. Similar percentages of patients had a CMV-specific immune response at baseline (71.7%) and at 48 weeks (70.0%). The magnitude of this response tended to increase over time [median 1.63 (IQR 0.15-5.77) IU/mL at baseline vs. median 2.5 (IQR 0.1-8.325) IU/mL at 48 weeks; P = 0.11]. We did not find any risk factors associated with 48-week mortality. CONCLUSIONS: Although the prevalence of CMV viraemia in patients with advanced HIV infection remains high, achieving a good immunological recovery through ART is enough to suppress CMV viraemia, without an increased risk of CMV EOD. The prevalence of a CMV-specific immune response was high and endured over time.


Assuntos
Infecções por Citomegalovirus , Infecções por HIV , Adulto , Contagem de Linfócito CD4 , Citomegalovirus , Infecções por Citomegalovirus/epidemiologia , Seguimentos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Pessoa de Meia-Idade , Prevalência , Carga Viral , Viremia
5.
Rev Clin Esp ; 2020 Feb 25.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32111438

RESUMO

OBJECTIVE: To identify the multidisciplinary uveitis units in which internal medicine departments participate in collaboration with ophthalmology departments in Spain. MATERIAL AND METHODS: We conducted a multicentre, observational cross-sectional study that collected information using a structured survey sent by email to 1015 partners of the Systemic Autoimmune Diseases Workgroup of the Spanish Society of Internal Medicine (GEAS-SEMI) from the 1st to the 31st of March 2017. RESULTS: We identified a total of 21 support units/consultations for the ophthalmology departments. Seventeen (81%) of the units were specific internal medicine-ophthalmology consultations, and 5 (24%) units had been created in the past 5 years. A median of 460 patients were assessed per unit by the end of the year. CONCLUSIONS: This study shows, for the first time in Spain, the important and close collaboration between ophthalmologists and internists, especially in highly specialised national reference institutions.

6.
Spinal Cord ; 56(8): 796-805, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29472608

RESUMO

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To assess the impact of spinal cord injury (SCI) on cognitive function in individuals with subacute and chronic SCI. SETTING: National Hospital for SCI patients (Spain). METHODS: The present investigation was designed to determine the nature, pattern, and extent of cognitive deficits in a group of participants with subacute (n = 32) and chronic (n = 34) SCI, using a comprehensive battery of reliable and validated neuropsychological assessments to study a broad range of cognitive functions. Twenty-seven able-bodied subjects matched to the groups with SCI for age and educational level formed the control group. RESULTS: The neuropsychological assessment showed alterations in the domain of attention, processing speed, memory and learning, executive functions, and in recognition in participants with SCI. The prevalence of cognitive dysfunction in the chronic stage was also confirmed at the individual level. The comparison of the neuropsychological assessment between the groups with subacute and chronic SCI showed a worsening of cognitive functions in those with chronic SCI compared to the group with subacute SCI. CONCLUSIONS: In participants with SCI, cognitive dysfunctions are present in the subacute stage and worsen over time. From a clinical point of view, we confirmed the presence of cognitive dysfunction that may interfere with the first stage of rehabilitation which is the most intense and important. Moreover, cognitive dysfunction may be important beyond the end of the first stage of rehabilitation as it can affect an individual's quality of life and possible integration to society.


Assuntos
Cognição , Disfunção Cognitiva/etiologia , Traumatismos da Medula Espinal/psicologia , Adulto , Fatores Etários , Doença Crônica , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Progressão da Doença , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Prevalência , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Traumatismos da Medula Espinal/fisiopatologia
7.
Ecol Lett ; 20(4): 471-476, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28239940

RESUMO

Determining statistical patterns irrespective of interacting agents (i.e. macroecology) is useful to explore the mechanisms driving population fluctuations and extinctions in natural food webs. Here, we tested four predictions of a neutral model on the distribution of community fluctuations (CF) and the distributions of persistence times (APT). Novel predictions for the food web were generated by combining (1) body size-density scaling, (2) Taylor's law and (3) low efficiency of trophic transference. Predictions were evaluated on an exceptional data set of plankton with 15 years of weekly samples encompassing c. 250 planktonic species from three trophic levels, sampled in the western English Channel. Highly symmetric non-Gaussian distributions of CF support zero-sum dynamics. Variability in CF decreased while a change from an exponential to a power law distribution of APT from basal to upper trophic positions was detected. Results suggest a predictable but profound effect of trophic position on fluctuations and extinction in natural communities.


Assuntos
Extinção Biológica , Cadeia Alimentar , Plâncton/fisiologia , Inglaterra , Modelos Biológicos , Oceanos e Mares , Dinâmica Populacional
8.
Nano Lett ; 16(8): 5204-12, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27390839

RESUMO

This paper investigates the electronic structure of wurtzite (W) and rock-salt (RS) Zn1-xCoxO nanoparticles (NPs) by means of optical measurements under pressure (up to 25 GPa), X-ray absorption, and transmission electron microscopy. W-NPs were chemically synthesized at ambient conditions and RS-NPs were obtained by pressure-induced transformation of W-NPs. In contrast to the abrupt phase transition in W-Zn1-xCoxO as thin film or single crystal, occurring sharply at about 9 GPa, spectroscopic signatures of tetrahedral Co(2+) are observed in NPs from ambient pressure to about 17 GPa. Above this pressure, several changes in the absorption spectrum reveal a gradual and irreversible W-to-RS phase transition: (i) the fundamental band-to-band edge shifts to higher photon energies; (ii) the charge-transfer absorption band virtually disappears (or overlaps the fundamental edge); and (iii) the intensity of the crystal-field absorption peaks of Co(2+) around 2 eV decreases by an order of magnitude and shifts to 2.5 eV. After incomplete phase transition pressure cycles, the absorption edge of nontransformed W-NPs at ambient pressure exhibits a blue shift of 0.22 eV. This extra shift is interpreted in terms of quantum confinement effects. The observed gradual phase transition and metastability are related to the NP size distribution: the larger the NP, the lower the W-to-RS transition pressure.

9.
Nanotechnology ; 27(2): 025701, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26618997

RESUMO

A structural transformation from the zircon-type structure to an amorphous phase has been found in YVO4:Eu(3+) nanoboxes at high pressures above 12.7 GPa by means of x-ray diffraction measurements. However, the pair distribution function of the high-pressure phase shows that the local structure of the amorphous phase is similar to the scheelite-type YVO4. These results are confirmed both by Raman spectroscopy and Eu(3+) photoluminescence which detect the phase transition to a scheelite-type structure at 10.1 and 9.1 GPa, respectively. The irreversibility of the phase transition is observed with the three techniques after a maximum pressure in the upstroke of around 20 GPa. The existence of two (5)D0-->(7)F0 photoluminescence peaks confirms the existence of two local environments for Eu(3+), at least for the low-pressure phase. One environment is the expected for substituting Y(3+) and the other is likely a disordered environment possibly found at the surface of the nanoboxes.

10.
Vox Sang ; 108(2): 169-77, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25469648

RESUMO

BACKGROUND AND OBJECTIVES: Instituto Clodomiro Picado has developed an immunoglobulin G (IgG) plasma fractionation process combining a polyethylene glycol/phosphate aqueous two-phase system (ATPS), caprylic acid precipitation and anion-exchange membrane chromatography. We evaluated the purity and in vitro thrombogenicity of such IgG, in line with current international requirements. MATERIALS AND METHODS: Contributions of the different production steps to reduce thrombogenicity were assessed at 0·2 l-scale, and then the methodology was scaled-up to a 10 l-scale and final products (n = 3) were analysed. Purity, immunoglobulin composition, and subclass distribution were determined by electrophoretic and immunochemical methods. The in vitro thrombogenic potential was determined by a thrombin generation assay (TGA) using a Technothrombin fluorogenic substrate. Prekallikrein activator (PKA), plasmin, factor Xa, thrombin and thrombin-like activities were assessed using S-2302, S-2251, S-2222, S-2238 and S-2288 chromogenic substrates, respectively, and FXI by an ELISA. RESULTS: The thrombogenicity markers were reduced mostly during the ATPS step and were found to segregate mostly into the discarded liquid upper phase. The caprylic acid precipitation eliminated the residual procoagulant activity. The IgG preparations made from the 10 l-batches contained 100% gamma proteins, low residual IgA and undetectable IgM. The IgG subclass distribution was not substantially affected by the process. TGA and amidolytic activities revealed an undetectable in vitro thrombogenic risk and the absence of proteolytic enzymes in the final product. CONCLUSIONS: Fractionating human plasma by an ATPS combined with caprylic acid and membrane chromatography resulted in an IgG preparation of high purity and free of a detectable in vitro thrombogenic risk.


Assuntos
Fracionamento Químico/métodos , Cromatografia/métodos , Imunoglobulina G/isolamento & purificação , Plasma/química , Caprilatos/química , Ensaio de Imunoadsorção Enzimática , Fator XIIa/análise , Humanos , Imunoglobulina G/química , Oligopeptídeos/química , Trombina/biossíntese
11.
Acta Biomater ; 178: 244-256, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460930

RESUMO

Guinea fowl eggshells have an unusual structural arrangement that is different from that of most birds, consisting of two distinct layers with different microstructures. This bilayered organization, and distinct microstructural characteristics, provides it with exceptional mechanical properties. The inner layer, constituting about one third of the eggshell thickness, contains columnar calcite crystal units arranged vertically as in most bird shells. However, the thicker outer layer has a more complex microstructural arrangement formed by a switch to smaller calcite domains with diffuse/interlocking boundaries, partly resembling the interfaces seen in mollusk shell nacre. The switching process that leads to this remarkable second-layer microstructure is unknown. Our results indicate that the microstructural switching is triggered by changes in the inter- and intracrystalline organic matrix. During production of the outer microcrystalline layer in the later stages of eggshell formation, the interactions of organic matter with mineral induce an accumulation of defects that increase crystal mosaicity, instill anisotropic lattice distortions in the calcite structure, interrupt epitaxial growth, reduce crystallite size, and induce nucleation events which increase crystal misorientation. These structural changes, together with the transition between the layers and each layer having different microstructures, enhance the overall mechanical strength of the Guinea fowl eggshell. Additionally, our findings provide new insights into how biogenic calcite growth may be regulated to impart unique functional properties. STATEMENT OF SIGNIFICANCE: Avian eggshells are mineralized to protect the embryo and to provide calcium for embryonic chick skeletal development. Their thickness, structure and mechanical properties have evolved to resist external forces throughout brooding, yet ultimately allow them to crack open during chick hatching. One particular eggshell, that of the Guinea fowl, has structural features very different from other galliform birds - it is bilayered, with an inner columnar mineral structure (like in most birds), but it also has an outer layer with a complex microstructure which contributes to its superior mechanical properties. This work provides novel and new fundamental information about the processes and mechanisms that control and change crystal growth during the switch to microcrystalline domains when the second outer layer forms.


Assuntos
Galinhas , Casca de Ovo , Animais , Casca de Ovo/química , Carbonato de Cálcio/química , Minerais
12.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230108, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38705190

RESUMO

Automated sensors have potential to standardize and expand the monitoring of insects across the globe. As one of the most scalable and fastest developing sensor technologies, we describe a framework for automated, image-based monitoring of nocturnal insects-from sensor development and field deployment to workflows for data processing and publishing. Sensors comprise a light to attract insects, a camera for collecting images and a computer for scheduling, data storage and processing. Metadata is important to describe sampling schedules that balance the capture of relevant ecological information against power and data storage limitations. Large data volumes of images from automated systems necessitate scalable and effective data processing. We describe computer vision approaches for the detection, tracking and classification of insects, including models built from existing aggregations of labelled insect images. Data from automated camera systems necessitate approaches that account for inherent biases. We advocate models that explicitly correct for bias in species occurrence or abundance estimates resulting from the imperfect detection of species or individuals present during sampling occasions. We propose ten priorities towards a step-change in automated monitoring of nocturnal insects, a vital task in the face of rapid biodiversity loss from global threats. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Assuntos
Inteligência Artificial , Insetos , Animais , Biodiversidade , Processamento de Imagem Assistida por Computador/métodos , Insetos/fisiologia
13.
Am J Transplant ; 13(10): 2730-3, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23914832

RESUMO

We describe a patient who underwent a successful heart and kidney transplant for light-chain amyloidosis. She had an excellent hematologic response to bortezomib/dexamethasone therapy. Follow-up therapy with lenalidomide was started, and the patient quickly had a fatal allograft rejection of the heart and kidney. We present evidence to support the theory that lenalidomide, a known immunomodulator, may have stimulated the immune system and precipitated the fatal rejection episode.


Assuntos
Amiloidose/tratamento farmacológico , Rejeição de Enxerto/induzido quimicamente , Transplante de Coração , Fatores Imunológicos/efeitos adversos , Transplante de Rim , Talidomida/análogos & derivados , Idoso , Aloenxertos , Amiloidose/metabolismo , Terapia Combinada , Feminino , Rejeição de Enxerto/mortalidade , Cardiopatias/tratamento farmacológico , Humanos , Cadeias Leves de Imunoglobulina/metabolismo , Nefropatias/tratamento farmacológico , Lenalidomida , Prognóstico , Talidomida/efeitos adversos
15.
J Pediatr Gastroenterol Nutr ; 56(5): 560-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23274339

RESUMO

OBJECTIVE: The objective of this work was to evaluate the effect of Holder pasteurisation of human colostrum on a variety of microbiological, biochemical, and immunological parameters. METHODS: Colostrum samples from 10 donors, and 8 samples of mature milk used as controls, were heated at 62.5°C for 30 minutes. Bacterial counts and the concentration of furosine, lactose, myoinositol, glucose, lactulose, cytokines, and immunoglobulins were determined before and after the heat treatment. RESULTS: Mean bacterial counts in nonpasteurised colostrum samples oscillated between 2.72 and 4.13 log10 colony-forming units per millilitre in the agar media tested. Holder pasteurisation led to the destruction of the bacteria originally present in the samples. Furosine was detected in all samples before pasteurisation and increased significantly after the heat treatment (from 6.60 to 20.59 mg/100 g protein). Lactulose content was below the detection limit in nonpasteurised colostrum, but it was detected in all samples and quantified in 7 of them (from 10.68 to 38.02 mg/L) after Holder pasteurisation. Lactose, glucose, and myoinositol concentrations did not change after Holder pasteurisation. The concentrations of most cytokines and immunoglobulins were significantly higher in colostrum than in mature milk samples. Immunoglobulin content, both in colostrum and in milk samples, was reduced during pasteurisation, whereas, among cytokines, only macrophage inflammatory protein-1ß, interleukin-7, and granulocyte-macrophage-colony-stimulating factor concentrations were affected by this heat treatment. CONCLUSIONS: Lactulose and furosine content could be used as heat treatment indicators in colostrum samples. Holder pasteurisation modified the immunological profile of both colostrum and mature milk.


Assuntos
Colostro , Citocinas/análise , Imunoglobulinas/análise , Lactulose/análise , Lisina/análogos & derivados , Pasteurização/métodos , Carga Bacteriana , Quimiocina CCL4/análise , Colostro/química , Colostro/imunologia , Colostro/microbiologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/análise , Temperatura Alta , Humanos , Interleucina-7/análise , Lisina/análise , Leite Humano/química , Leite Humano/imunologia , Leite Humano/microbiologia
16.
Plant Dis ; 97(6): 838, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30722608

RESUMO

In December 2011, edible sunflower sprouts (Helianthus annus) of two different commercially grown cultivars (Sungrown and Tiensvold) exhibiting stem and cotyledon lesions were submitted to the New Mexico State University Plant Clinic for disease diagnosis. The sample originated from an organic farm in Santa Fe County where the grower utilizes a small indoor growing facility. Stem lesions were elongate, reddish brown, and often constricted, resulting in stem girdling. Lesions on the cotyledons were dark brown with tan centers and round to irregular in shape. In some cases, the entire cotyledon was blighted. Fungal hyphae were observed on some lesions using a dissecting microscope. Colletotrichum acutatum was isolated from stem and cotyledon lesions when symptomatic tissue was plated on water agar. Conidia were fusiform ranging from 6.4 to 18.4 µm long and 2.1 to 5.1 µm wide and averaged 11.9 µm × 3.4 µm. Spores were measured from cream-colored colonies produced on acidified potato dextrose agar. PCR amplification and sequence analysis of 5.8S ribosomal DNA and internal transcribed spacers I and II was performed using primers ITS4 and ITS6 (2). An amplification product of approximately 600 base pairs in size was directly sequenced (GenBank Accession No. JX444690). A BLAST search of the NCBI total nucleotide collection revealed a 99% identity to multiple C. acutatum (syn: C. simmondsii) isolates. Four isolates were identified as C. acutatum based on morphological characteristics and DNA analysis. Koch's postulates were performed using four isolates of the pathogen and the two commercial sunflower cultivars (Sungrown and Tiensvold) originally submitted for disease analysis. Sunflower seeds were imbibed in distilled water for 24 h then sewn into peat plugs. Prior to seed germination, 5 ml of a C. acutatum spore solution (1 × 106/ml) from each isolate was applied to five peat plugs using an atomizer. Control plants were inoculated with distilled water and otherwise treated identically. Both sunflower cultivars were inoculated with each isolate of the pathogen and the test was replicated twice. The sewn peat plugs were incubated for 5 days at 21°C and 50% relative humidity. Symptoms similar to the original samples were present on 100% of the sprouts after 5 days. PCR and sequence analysis performed on cultures obtained from lesions showed a 100% match to the original New Mexico isolates fulfilling Koch's postulates. In an indoor organic facility, such as the one in NM, this disease has the potential to be very difficult to manage and the potential to infect a high percentage of the crop resulting in significant economic losses. To our knowledge, this is the second report of C. acutatum on sunflower sprouts in the United States (1) and the first report in New Mexico. References: (1) S. T. Koike et al. Plant Dis. 93:1351, 2009. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

17.
Nat Commun ; 14(1): 2973, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221181

RESUMO

Single immune checkpoint blockade in advanced neuroendocrine neoplasms (NENs) shows limited efficacy; dual checkpoint blockade may improve treatment activity. Dune (NCT03095274) is a non-randomized controlled multicohort phase II clinical trial evaluating durvalumab plus tremelimumab activity and safety in advanced NENs. This study included 123 patients presenting between 2017 and 2019 with typical/atypical lung carcinoids (Cohort 1), G1/2 gastrointestinal (Cohort 2), G1/2 pancreatic (Cohort 3) and G3 gastroenteropancreatic (GEP) (Cohort 4) NENs; who progressed to standard therapies. Patients received 1500 mg durvalumab and 75 mg tremelimumab for up to 13 and 4 cycles (every 4 weeks), respectively. The primary objective was the 9-month clinical benefit rate (CBR) for cohorts 1-3 and 9-month overall survival (OS) rate for Cohort 4. Secondary endpoints included objective response rate, duration of response, progression-free survival according to irRECIST, overall survival, and safety. Correlation of PD-L1 expression with efficacy was exploratory. The 9-month CBR was 25.9%/35.5%/25% for Cohorts 1, 2, and 3 respectively. The 9-month OS rate for Cohort 4 was 36.1%, surpassing the futility threshold. Benefit in Cohort 4 was observed regardless of differentiation and Ki67 levels. PD-L1 combined scores did not correlate with treatment activity. Safety profile was consistent with that of prior studies. In conclusion, durvalumab plus tremelimumab is safe in NENs and shows modest survival benefit in G3 GEP-NENs; with one-third of these patients experiencing a prolonged OS.


Assuntos
Tumor Carcinoide , Tumores Neuroendócrinos , Humanos , Antígeno B7-H1 , Pulmão
18.
Phys Rev Lett ; 108(16): 166402, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22680738

RESUMO

High-pressure optical-absorption measurements performed in CuWO(4) up to 20 GPa provide experimental evidence of the persistence of the Jahn-Teller (JT) distortion in the whole pressure range both in the low-pressure triclinic and in the high-pressure monoclinic phase. The electron-lattice couplings associated with the e(g)(E⊗e) and t(2g)(T⊗e) orbitals of Cu(2+) in CuWO(4) are obtained from correlations between the JT distortion of the CuO(6) octahedron and the associated structure of Cu(2+) d-electronic levels. This distortion and its associated JT energy (E(JT)) decrease upon compression in both phases. However, both the distortion and associated E(JT) increase sharply at the phase-transition pressure (P(PT)=9.9 GPa), and we estimate that the JT distortion persists for a wide pressure range not being suppressed up to 37 GPa. These results shed light on the transition mechanism of multiferroic CuWO(4), suggesting that the pressure-induced structural phase transition is a way to minimize the distortive effects associated with the toughness of the JT distortion.

19.
Mar Environ Res ; 177: 105636, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35569182

RESUMO

Seagrass ecosystems usually respond in a nonlinear fashion to increasing pressures and environmental changes. Feedback mechanisms operating at the ecosystem level and involving multiple interactions among the seagrass meadow, its associated community and the physical environment are known to play a major role in such nonlinear responses. Phenotypic plasticity may also be important for buffering these ecological thresholds (i.e., regime shifts) as many physiological processes show nonlinear responses to gradual environmental changes, conferring the appearance of resistance before the effects at the organism and population levels are visible. However, the potential involvement of plant plasticity in driving catastrophic shifts in seagrass ecosystems has not yet been assessed. In this study, we conducted a manipulative 6-month light-gradient experiment in the field to capture nonlinearities of the physiological and population responses of the seagrass Cymodocea nodosa to gradual light reduction. The aim was to explore if and how the photo-acclimatory responses of shaded plants are translated to the population level and, hence, to the ecosystem level. Results showed that the seagrass population was rather stable under increasing shading levels through the activation of multilevel photo-acclimative responses, which are initiated with light reduction and modulated in proportion to shading intensity. The activation of photo-physiological and metabolic compensatory responses allowed shaded plants to sustain nearly constant plant productivity (metabolic carbon balance) along a range of shading levels before losing linearity and starting to decline. The species then activated plant- and meadow-scale photo-acclimative responses and drew on its energy reserves (rhizome carbohydrates) to confer additional population resilience. However, when the integration of all these buffering mechanisms failed to counterbalance the effects of extreme light limitation, the population collapsed, giving place to a phase shift from vegetated to bare sediments with catastrophic ecosystem outcomes. Our findings evidence that ecological thresholds in seagrass ecosystems under light limitation can be explained by the role of species' compensatory responses in modulating population-level responses. The thresholds of these plastic responses anticipate the sudden loss of seagrass meadows with the potential to be used as early warning indicators signalling the imminent collapse of the ecosystem, which is of great value for the real-world management of seagrass ecosystems.


Assuntos
Alismatales , Ecossistema , Aclimatação , Alismatales/fisiologia , Carbono/metabolismo , Meio Ambiente
20.
Breast Dis ; 41(1): 97-108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34542055

RESUMO

INTRODUCTION: The Objective was to investigate the incidence of lymphedema after breast cancer treatment and to analyze the risk factors involved in a tertiary level hospital. METHODS: Prospective longitudinal observational study over 3 years post-breast surgery. 232 patients undergoing surgery for breast cancer at our institution between September 2013 and February 2018. Sentinel lymph node biopsy (SLNB) or axillary lymphadenectomy (ALND) were mandatory in this cohort. In total, 201 patients met the inclusion criteria and had a median follow-up of 31 months (range, 1-54 months). Lymphedema was diagnosed by circumferential measurements and truncated cone calculations. Patients and tumor characteristics, shoulder range of motion limitation and local and systemic therapies were analyzed as possible risk factors for lymphedema. RESULTS: Most cases of lymphedema appeared in the first 2 years. 13.9% of patients developed lymphedema: 31% after ALND and 4.6% after SLNB (p < 0.01), and 46.7% after mastectomy and 11.3% after breast-conserving surgery (p < 0.01). The lymphedema rate increased when axillary radiotherapy (RT) was added to radical surgery: 4.3% for SLNB alone, 6.7% for SLNB + RT, 17.6% for ALND alone, and 35.2% for ALND + RT (p < 0.01). In the multivariate analysis, the only risk factors associated with the development of lymphedema were ALND and mastectomy, which had hazard ratios (95% confidence intervals) of 7.28 (2.92-18.16) and 3.9 (1.60-9.49) respectively. CONCLUSIONS: The main risk factors for lymphedema were the more radical surgeries (ALND and mastectomy). The risk associated with these procedures appeared to be worsened by the addition of axillary radiotherapy. A follow-up protocol in patients with ALND lasting at least two years, in which special attention is paid to these risk factors, is necessary to guarantee a comprehensive control of lymphedema that provides early detection and treatment.


Assuntos
Neoplasias da Mama/cirurgia , Linfedema/etiologia , Mastectomia/efeitos adversos , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Idoso , Axila/patologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Biópsia de Linfonodo Sentinela/métodos , Centros de Atenção Terciária/estatística & dados numéricos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA