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1.
J Exp Bot ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046305

RESUMEN

Lichens are a mutualistic symbiosis between a fungus and one or more photosynthetic partners. They are photosynthetically active during desiccation until relative water contents (RWC) as low as 30% (on dry mass). Experimental evidence suggests that during desiccation, the photobionts have a higher hydration level than the surrounding fungal pseudo-tissues. Explosive cavitation events in the hyphae might cause water movements towards the photobionts. This hypothesis was tested in two foliose lichens by measurements of ultrasonic acoustic emissions (UAE), a method commonly used in vascular plants but never in lichens, and by measurements of photosystem II efficiency, water potential and RWC. Thallus structural changes were characterised by low-temperature scanning electron microscopy. The thalli were silent between 380% and 30% RWCs, i.e. when explosive cavitation events should cause movements of liquid water. Nevertheless, the thalli emitted UAE at approximately 5% RWC. Accordingly, the medullary hyphae were partially shrunk at about 15% RWC, whereas they were completely shrunk below 5% RWC. These results do not support the hypothesis of hyphal cavitation and suggest that the UAE originate from structural changes at hyphal level. The shrinking of hyphae is proposed as an adaptation to avoid cell damage at very low RWCs.

2.
BMC Med Imaging ; 23(1): 153, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821840

RESUMEN

BACKGROUND: Cervical cancer patients receiving radiotherapy and chemotherapy require accurate survival prediction methods. The objective of this study was to develop a prognostic analysis model based on a radiomics score to predict overall survival (OS) in cervical cancer patients. METHODS: Predictive models were developed using data from 62 cervical cancer patients who underwent radical hysterectomy between June 2020 and June 2021. Radiological features were extracted from T2-weighted (T2W), T1-weighted (T1W), and diffusion-weighted (DW) magnetic resonance images prior to treatment. We obtained the radiomics score (rad-score) using least absolute shrinkage and selection operator (LASSO) regression and Cox's proportional hazard model. We divided the patients into low- and high-risk groups according to the critical rad-score value, and generated a nomogram incorporating radiological features. We evaluated the model's prediction performance using area under the receiver operating characteristic (ROC) curve (AUC) and classified the participants into high- and low-risk groups based on radiological characteristics. RESULTS: The 62 patients were divided into high-risk (n = 43) and low-risk (n = 19) groups based on the rad-score. Four feature parameters were selected via dimensionality reduction, and the scores were calculated after modeling. The AUC values of ROC curves for prediction of 3- and 5-year OS using the model were 0.84 and 0.93, respectively. CONCLUSION: Our nomogram incorporating a combination of radiological features demonstrated good performance in predicting cervical cancer OS. This study highlights the potential of radiomics analysis in improving survival prediction for cervical cancer patients. However, further studies on a larger scale and external validation cohorts are necessary to validate its potential clinical utility.


Asunto(s)
Radiología , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/cirugía , Nomogramas , Imagen por Resonancia Magnética , Cuello , Estudios Retrospectivos
4.
Ann Bot ; 129(6): 737-751, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35390119

RESUMEN

BACKGROUND AND AIMS: The lowlands of South America appear to be remarkably important in the evolutionary history of maize, due to new evidence that suggests that maize dispersed from Mexico and arrived in this region in a state of partial domestication. This study aimed to identify dispersal patterns of maize genetic diversity in this part of the continent. METHODS: A total of 170 maize accessions were characterized with 4398 single nucleotide polymorphisms (SNPs) and analysed to determine if maize dispersal was associated with types of endosperm and indigenous language families. KEY RESULTS: Four genetic groups were identified in the discriminant analysis of principal components and five groups in the cluster analysis (neighbour-joining method). The groups were structured according to the predominance of endosperm types (popcorn, floury, flint/semi-flint). Spatial principal component analysis of genetic variation suggests different dispersal patterns for each endosperm type and can be associated with hypotheses of expansions of different indigenous groups. CONCLUSIONS: From a possible origin in Southwestern Amazonia, different maize dispersal routes emerged: (1) towards Northern Amazonia, which continued towards the Caatinga and south-eastern Atlantic Forest (Floury); (2) towards Southern Brazil, passing through the Cerrado and Southern Atlantic Forest reaching the Pampa region (Floury); and (3) along the Atlantic Coast, following Tupi movements originating from two separate expansions: one (Tupinamba) from north to south, and the other (Guarani) in the opposite direction, from south to north (flint, floury and popcorn).


Asunto(s)
Endospermo , Zea mays , Brasil , Endospermo/genética , Variación Genética , Humanos , Polimorfismo de Nucleótido Simple , América del Sur , Zea mays/genética
5.
J Surg Oncol ; 125(2): 194-216, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34585390

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the third leading cause of cancer in North America, Western Europe, and Brazil, and represents an important public health problem. It is estimated that approximately 30% of all the CRC cases correspond to tumors located in the rectum, requiring complex multidisciplinary treatment. In an effort to provide surgeons who treat rectal cancer with the most current information based on the best evidence in the literature, the Brazilian Society of Surgical Oncology (SBCO) has produced the present guidelines for rectal cancer treatment that is focused on the main topics related to daily clinical practice. OBJECTIVES: The SBCO developed the present guidelines to provide recommendations on the main topics related to the treatment of mid-low rectal cancer based on current scientific evidence. METHODS: Between May and June 2021, 11 experts in CRC surgery met to develop the guidelines for the treatment of mid-low rectal cancer. A total of 22 relevant topics were disseminated among the participants. The methodological quality of a final list with 221 sources was evaluated, all the evidence was examined and revised, and the treatment guideline was formulated by the 11-expert committee. To reach a final consensus, all the topics were reviewed via a videoconference meeting that was attended by all 11 of the experts. RESULTS: The prepared guidelines contained 22 topics considered to be highly relevant in the treatment of mid-low rectal cancer, covering subjects related to the tests required for staging, surgical technique-related aspects, recommended measures to reduce surgical complications, neoadjuvant strategies, and nonoperative treatments. In addition, a checklist was proposed to summarize the important information and offer an updated tool to assist surgeons who treat rectal cancer provide the best care to their patients. CONCLUSION: These guidelines summarize concisely the recommendations based on the most current scientific evidence on the most relevant aspects of the treatment of mid-low rectal cancer and are a practical guide that can help surgeons who treat rectal cancer make the best therapeutic decision.


Asunto(s)
Guías de Práctica Clínica como Asunto , Neoplasias del Recto/cirugía , Brasil , Humanos , Escisión del Ganglio Linfático , Procedimientos Quirúrgicos Mínimamente Invasivos , Terapia Neoadyuvante , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Sociedades Médicas , Oncología Quirúrgica , Infección de la Herida Quirúrgica/prevención & control
6.
BMC Plant Biol ; 21(1): 96, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33596835

RESUMEN

BACKGROUND: Assessment and effective utilization of genetic diversity in breeding programs is crucial for sustainable genetic improvement and rapid adaptation to changing breeding objectives. During the past two decades, the commercialization of the early and extra-early maturing cultivars has contributed to rapid expansion of maize into different agro-ecologies of sub-Saharan Africa (SSA) where maize has become an important component of the agricultural economy and played a vital role in food and nutritional security. The present study aimed at understanding the population structure and genetic variability among 439 early and extra-early maize inbred lines developed from three narrow-based and twenty-seven broad-based populations by the International Iinstitute of Tropical Agriculture Maize Improvement Program (IITA-MIP). These inbreds were genotyped using 9642 DArTseq-based single nucleotide polymorphism (SNP) markers distributed uniformly throughout the maize genome. RESULTS: About 40.8% SNP markers were found highly informative and exhibited polymorphic information content (PIC) greater than 0.25. The minor allele frequency and PIC ranged from 0.015 to 0.500 and 0.029 to 0.375, respectively. The STRUCTURE, neighbour-joining phylogenetic tree and principal coordinate analysis (PCoA) grouped the inbred lines into four major classes generally consistent with the selection history, ancestry and kernel colour of the inbreds but indicated a complex pattern of the genetic structure. The pattern of grouping of the lines based on the STRUCTURE analysis was in concordance with the results of the PCoA and suggested greater number of sub-populations (K = 10). Generally, the classification of the inbred lines into heterotic groups based on SNP markers was reasonably reliable and in agreement with defined heterotic groups of previously identified testers based on combining ability studies. CONCLUSIONS: Complete understanding of potential heterotic groups would be difficult to portray by depending solely on molecular markers. Therefore, planned crosses involving representative testers from opposing heterotic groups would be required to refine the existing heterotic groups. It is anticipated that the present set of inbreds could contribute new beneficial alleles for population improvement, development of hybrids and lines with potential to strengthen future breeding programs. Results of this study would help breeders in formulating breeding strategies for genetic enhancement and sustainable maize production in SSA.


Asunto(s)
Variación Genética , Zea mays/crecimiento & desarrollo , Zea mays/genética , Adaptación Fisiológica , África del Sur del Sahara , Alelos , Vigor Híbrido , Filogenia , Fitomejoramiento , Polimorfismo de Nucleótido Simple , Zea mays/clasificación , Zea mays/fisiología
7.
Mediators Inflamm ; 2020: 8405370, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32410868

RESUMEN

Myocardial ischemia reperfusion syndrome is a complex entity where many inflammatory mediators play different roles, both to enhance myocardial infarction-derived damage and to heal injury. In such a setting, the establishment of an effective therapy to treat this condition has been elusive, perhaps because the experimental treatments have been conceived to block just one of the many pathogenic pathways of the disease, or because they thwart the tissue-repairing phase of the syndrome. Either way, we think that a discussion about the pathophysiology of the disease and the mechanisms of action of some drugs may shed some clarity on the topic.


Asunto(s)
Isquemia Miocárdica/patología , Isquemia Miocárdica/terapia , Daño por Reperfusión/patología , Daño por Reperfusión/terapia , Animales , Humanos , Inmunidad Innata , Terapia de Inmunosupresión , Inflamación , Mediadores de Inflamación , Isquemia , Ratones , Infarto del Miocardio/terapia , Reperfusión Miocárdica , Daño por Reperfusión Miocárdica/prevención & control , Fenotipo , Células TH1/citología , Células Th2/citología
8.
BMC Evol Biol ; 19(1): 28, 2019 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-30665356

RESUMEN

BACKGROUND: The polyamine oxidases (PAOs) catabolize the oxidative deamination of the polyamines (PAs) spermine (Spm) and spermidine (Spd). Most of the phylogenetic studies performed to analyze the plant PAO family took into account only a limited number and/or taxonomic representation of plant PAOs sequences. RESULTS: Here, we constructed a plant PAO protein sequence database and identified four subfamilies. Subfamily PAO back conversion 1 (PAObc1) was present on every lineage included in these analyses, suggesting that BC-type PAOs might play an important role in plants, despite its precise function is unknown. Subfamily PAObc2 was exclusively present in vascular plants, suggesting that t-Spm oxidase activity might play an important role in the development of the vascular system. The only terminal catabolism (TC) PAO subfamily (subfamily PAOtc) was lost in Superasterids but it was present in all other land plants. This indicated that the TC-type reactions are fundamental for land plants and that their function could being taken over by other enzymes in Superasterids. Subfamily PAObc3 was the result of a gene duplication event preceding Angiosperm diversification, followed by a gene extinction in Monocots. Differential conserved protein motifs were found for each subfamily of plant PAOs. The automatic assignment using these motifs was found to be comparable to the assignment by rough clustering performed on this work. CONCLUSIONS: The results presented in this work revealed that plant PAO family is bigger than previously conceived. Also, they delineate important background information for future specific structure-function and evolutionary investigations and lay a foundation for the deeper characterization of each plant PAO subfamily.


Asunto(s)
Modelos Moleculares , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/química , Plantas/enzimología , Análisis de Secuencia de Proteína , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Dominio Catalítico , Análisis por Conglomerados , Bases de Datos de Proteínas , Filogenia , Dominios Proteicos , Homología Estructural de Proteína , Poliamino Oxidasa
9.
Clin Cases Miner Bone Metab ; 14(3): 340-346, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29354165

RESUMEN

Soft-tissue filler (STF) injections have been used worldwide for cosmetic reasons. In most cases, they are not approved by the United States Food and Drug Administration (FDA). Regulatory boards in Latin American countries do not allow the medical use of STF injections; however, these injections are still widely used. A case of calcitriol-mediated hypercalcemia with ectopic calcifications, chronic kidney disease, nephrolithiasis and calcinosis is presented. The reported case highlights the consequences of STF use, including calcitriol-mediated hypercalcemia secondary to granulomatous reactions years after an esthetic procedure.

11.
J Comput Assist Tomogr ; 40(6): 896-898, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27759601

RESUMEN

Intramural hematomas can occur along any part of the gastrointestinal tract, being more common in the duodenum, jejunum, and ileum. Intramural colonic hematomas are very rare, and their main causes include abdominal trauma, anticoagulation, and coagulopathies. We report on a 27-year-old man with right lower quadrant pain for 1 day after a mild blunt trauma sustained during a soccer match. Computed tomography and magnetic resonance imaging evaluation revealed an intramural hematoma of the right colon, subsequently confirmed and drained through laparoscopic surgery. Although computed tomography and magnetic resonance imaging findings in such a context are scarce in the radiological literature, imaging has an important role in the preoperative diagnosis and evaluation of the extent of bowel hematomas to assist in treatment planning.


Asunto(s)
Traumatismos Abdominales/diagnóstico por imagen , Enfermedades del Colon/diagnóstico por imagen , Hematoma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Heridas no Penetrantes/diagnóstico por imagen , Traumatismos Abdominales/complicaciones , Adulto , Enfermedades del Colon/etiología , Enfermedades del Colon/cirugía , Diagnóstico Diferencial , Hematoma/etiología , Hematoma/cirugía , Humanos , Masculino , Heridas no Penetrantes/complicaciones
12.
Oncologist ; 20(4): 386-92, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25746343

RESUMEN

BACKGROUND AND OBJECTIVE: Hematopoietic stem cell transplantation (HSCT) in developing countries is cost-limited. Our primary goal was to determine the cost structure for the HSCT program model developed over the last decade at our public university hospital and to assess its clinical outcomes. MATERIALS AND METHODS: Adults and children receiving an allogeneic hematopoietic stem cell transplant from January 2010 to February 2011 at our hematology regional reference center were included. Laboratory tests, medical procedures, chemotherapy drugs, other drugs, and hospitalization costs were scrutinized to calculate the total cost for each patient and the median cost for the procedure. Data regarding clinical evolution were incorporated into the analysis. Physician fees are not charged at the institution and therefore were not included. RESULTS: Fifty patients were evaluated over a 1-year period. The total estimated cost for an allogeneic HSCT was $12,504. The two most expensive diseases to allograft were non-Hodgkin lymphoma ($11,760 ± $2,236) for the malignant group and thalassemia ($12,915 ± $5,170) for the nonmalignant group. Acute lymphoblastic leukemia ($11,053 ± 2,817) and acute myeloblastic leukemia ($10,251 ± $1,538) were the most frequent indications for HSCT, with 11 cases each. Median out-of-pocket expenses were $1,605, and 1-year follow-up costs amounted to $1,640, adding up to a total cost of $15,749 for the first year. The most expensive components were drugs and laboratory tests. CONCLUSION: Applying the cost structure described, HSCT is an affordable option for hematological patients living in a developing country.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/economía , Costos y Análisis de Costo , Países en Desarrollo , Femenino , Humanos , Leucemia Mieloide Aguda/terapia , Linfoma no Hodgkin/terapia , Masculino , México , Talasemia/terapia , Trasplante Homólogo/economía , Resultado del Tratamiento
16.
Front Allergy ; 5: 1384140, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38720769

RESUMEN

Progesterone is an endogenous hormone, produced by the adrenal cortex, the gonads and in women, its source is the corpus luteum. Progesterone is produced in the late phase of the menstrual cycle, when implantation of the zygote does not occur, the corpus luteum involutes and the release of progesterone is suppressed, thus initiating menstruation. Progestogen Hypersensitivity were initially identified as hormone allergy and were related to endogenous reactions to hormones and alteration of ovarian function. Skin manifestations such as dermatitis or urticaria were initially reported and described as progesterone autoimmune dermatitis, although the immune-mediated mechanism was not clear. Currently there is no standardization for in vivo or in vitro tests for Progestogen Hypersensitivity diagnosis. In this review, we will address the different diagnostic methods of this disease.

17.
medRxiv ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38699295

RESUMEN

BACKGROUND: Prediabetes has been associated with increased all-cause and cardiovascular mortality. However, no large-scale studies have been conducted in Mexico or Latin America examining these associations. METHODS: We analyzed data from 115,919 adults without diabetes (diagnosed or undiagnosed) aged 35-84 years who participated in the Mexico City Prospective Study between 1998 and 2004. Participants were followed until January 1st, 2021 for cause-specific mortality. We defined prediabetes according to the American Diabetes Association (ADA, HbA1c 5.7% to 6.4%) and the International Expert Committee (IEC, HbA1c 6.0-6.4%) definitions. Cox regression adjusted for confounders was used to estimate all-cause and cause-specific mortality rate ratios (RR) at ages 35-74 years associated with prediabetes. FINDINGS: During 2,085,392 person-years of follow-up (median in survivors 19 years), there were 6,810 deaths at ages 35-74, including 1,742 from cardiovascular disease, 892 from renal disease and 108 from acute diabetic crises. Of 110,405 participants aged 35-74 years at recruitment, 28,852 (26%) had ADA-defined prediabetes and 7,203 (7%) had IEC-defined prediabetes. Compared with those without prediabetes, individuals with prediabetes had higher risk of all-cause mortality at ages 35-74 years (RR 1.13, 95% CI 1.07-1.19 for ADA-defined prediabetes and RR 1.28, 1.18-1.39 for IEC-defined prediabetes), as well as increased risk of cardiovascular mortality (RR 1.22 [1.10-1.35] and 1.42 [1.22-1.65], respectively), renal mortality (RR 1.35 [1.08-1.68] and 1.69 [1.24-2.31], respectively), and death from an acute diabetic crisis (RR 2.63 [1.76-3.94] and 3.43 [2.09-5.62], respectively). RRs were larger at younger than at older ages, and similar for men compared to women. The absolute excess risk associated with ADA and IEC-defined prediabetes at ages 35-74 accounted for6% and 3% of cardiovascular deaths respectively, 10% and 5% of renal deaths respectively, and 31% and 14% of acute diabetic deaths respectively. INTERPRETATION: Prediabetes is a significant risk factor for all-cause, cardiovascular, renal, and acute diabetic deaths in Mexican adults. Identification and timely management of individuals with prediabetes for targeted risk reduction could contribute to reducing premature mortality from cardiometabolic causes in this population. FUNDING: Wellcome Trust, the Mexican Health Ministry, the National Council of Science and Technology for Mexico, Cancer Research UK, British Heart Foundation, UK Medical Research Council. Instituto Nacional de Geriatría (Mexico City).

19.
Funct Plant Biol ; 50(5): 407-415, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36958768

RESUMEN

We aimed at exploring the plant functional traits whose responses to drought or salinity are altered by the presence of arbuscular mycorrhiza (AM). We performed a meta-analysis across 114 articles spanning 110 plant species or cultivars. We quantified the size effect of AM symbiosis on the stress response of several functional traits, using linear mixed model analysis (LMM). Correlation analysis between functional traits and total biomass responses to stresses were also performed through LMM. The literature search and further selection yielded seven functional traits, extracted from 114 laboratory studies, including 888 observations and 110 plant species/cultivars. Evidence for significant effects of predictor variables (type of stress, AM symbiosis and/or their interaction) on functional trait response were found for leaf area ratio (LAR), root mass fraction (RMF) and root-shoot (R:S) ratio. Our results provided evidence to accept the hypothesis that AM fungal inoculation may reduce the stress response of these plant functional traits by decreasing its magnitude. We also found a weak correlation between stress responses of these traits and total biomass variation. Although our literature search and data collection were intensive and our results robust, the scope of our conclusions is limited by the agronomical bias of plant species targeted by the meta-analysis. Further knowledge on non-cultivable plant species and better understanding of the mechanisms ruling resources allocation in plants would allow more generalised conclusions.


Asunto(s)
Micorrizas , Micorrizas/fisiología , Simbiosis/fisiología , Raíces de Plantas , Sequías , Salinidad , Plantas
20.
Heart Rhythm ; 20(12): 1674-1681, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37598986

RESUMEN

BACKGROUND: Infection is the most dreaded complication of cardiac implantable electronic devices (CIEDs), particularly in patients undergoing high-risk procedures (eg, generator change, device upgrade, lead/pocket revision). OBJECTIVE: The purpose of this study was to describe the impact of chlorhexidine gluconate (CHG) pocket lavage in high-risk procedures. METHODS: Patients from a prospective multicenter registry undergoing high-risk procedures were included. CHG lavage was performed by irrigating the generator pocket with 20 cc of 2% CHG without alcohol followed by and normal saline (NS) irrigation. Only NS irrigation was performed in the comparison group. The primary efficacy outcome was CIED-related infection at 12 months. The primary safety outcome was any CHG-associated adverse event. The secondary outcome was CIED infection during long-term follow-up. Propensity score matching (PSM) analysis was performed for the primary efficacy outcome. RESULTS: A total of 1504 patients were included. At 12-month follow-up, the primary efficacy outcome occurred in 4 of 904 CHG (0.4%) and 14 of 600 NS (2.3%) subjects (log-rank P = .005). On multivariate analysis, the use of CHG irrigation was associated with a lower risk of infection at 1-year follow-up (Cox proportional hazard ratio [HR] 0.138; 95% confidence interval [CI] 0.04-0.45; P = .001). This effect persisted during long-term follow-up. PSM demonstrated a significant reduction in CIED-related infection for the CHG group (0.2% vs 2.5%; Cox proportional HR 0.08; 95% CI 0.01-0.59; P = .014). No adverse events were associated with the use of CHG. CONCLUSION: CHG lavage during high-risk procedures was associated with a reduction in CIED-related infections without any adverse events reported. The benefits of CHG lavage were observed even during long-term follow up and in PSM analysis.


Asunto(s)
Desfibriladores Implantables , Cardiopatías , Marcapaso Artificial , Infecciones Relacionadas con Prótesis , Humanos , Desfibriladores Implantables/efectos adversos , Cardiopatías/etiología , Marcapaso Artificial/efectos adversos , Estudios Prospectivos , Infecciones Relacionadas con Prótesis/etiología , Infecciones Relacionadas con Prótesis/prevención & control , Irrigación Terapéutica
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